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West Area Recorder Colin Jakes, 7 Maltward Avenue, BURY ST EDMUNDS IP33 3XN Tel: 01284 702215

North-East Area Recorder Andrew Green, 17 Cherrywood, HARLESTON Norfolk IP20 9LP Tel: 07766 900063 E-mail: andrew@waveney1 fsnet.co.uk

1

South-East Area Recorder Eddie Marsh, 17 Post Mill Gardens, GRUNDISBURGH, IP13 6UP Tel: 01473 735425 E-mail: marshharrier@btinternet.com

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SUFFOLK BIRDS VOL. 56 A review of birds in Suffolk in 2006

Editor Malcolm Wright

Assisted by Adam Gretton (Papers) Philip Murphy (Systematic List) Trevor Kerridge (Photos) Tony Howe (Artwork)

Published by SUFFOLK NATURALISTS' SOCIETY in collaboration with SUFFOLK ORNITHOLOGISTS' GROUP 2007


Published by The Suffolk Naturalists' Society, c/o The M u s e u m , High Street, Ipswich IP1 3 Q H Š The Suffolk Naturalists' Society 2007 All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without prior permission of the Copyright owners.

The SNS is a Registered Charity No. 206084.

ISSN 0 2 6 4 - 5 7 9 3

Printed by Healeys Printers Ltd, Unit 10-11, The Sterling Complex, Farthing Road, Ipswich, Suffolk IP1 5AP.


CONTENTS Page Editorial Malcolm

Wright

5

Review of the Year Malcolm Wright

7

Lakenheath Fen - the First Ten Years Norman Sills

10

Roof-nesting Gulls at the Port of Felixstowe Peter Rock

17

The Return of the Buzzard to Suffolk Chris Gregory

22

Spring Movements of Common Buzzards along the Suffolk Coast Peter Dare

27

Recent Amendments to the Suffolk List Philip Murphy, Brian Small, Malcolm Wright and Justin Zantboer

39

The 2006 Suffolk Bird Report: Introduction

43

Systematic List

45

Appendices

155

List of Contributors

160

Gazetteer

162

Earliest and Latest Dates of Summer Migrants

164

A Guide to Recording Birds in Suffolk

165

Rare Birds in Suffolk 2006 David Walsh

169

Regional Review Adam Gretton

173

Suffolk Ringing Report 2006 Peter Lack

181

List of Plates Plate No.

Easton

97

Easton

97

48

13. Ross's Gull Andrew 14. Ross's Gull Andrew

48 49

Easton 15. Little Tern Andrew 16. Redwing Bill Bastón

49

17. Dartford Warbler Bill Bastón 18. Red-flanked Bluetail Bill Bastón

97 144 144

96

19. Red-backed Shrike Alan Tate 20. Lesser Grey Shrike Bill Bastón 21. Treecreepers Bill Bastón

96

22. Linnet Bill

96

23. Arctic Redpoll Sean Nixon 24. Lapland Bunting Mark Breaks

145 145

1. Lakenheath Fen Mike Page 2. Lakenheath Fen Norman Sills 3. Lesser Scaup Alan Tate 4. Smew Bill Boston

48

5. Cormorants Andrew 6. Osprey Bill Boston 7. Buzzard Alan Tate

8. Red-footed Falcon Mike Parker 9. Bar-tailed Godwit Alan Tate 10. Greenshank Clive Naunton 11. Turnstone Andrew Easton 12. Arctic Skua Andrew Easton

Page

No.

Page

Easton

Facing

Plate

Facing

49 49 96

96

Bastón

F r o n t c o v e r : R e d - f l a n k e d B l u e t a i l Brian

Small

T h e c o p y r i g h t r e m a i n s t h a t o f the p h o t o g r a p h e r s a n d artists

3

97 97

144 145

145


Suffolk Birci Report

2006

Notice to Contributors Suffolk Birds is an annual publication of records, notes and papers on all aspects of Suffolk ornithology. Except for records and field descriptions submitted through the county recorders, all material should be original. It should not have been published elsewhere or offered complete or in part to any other journal. Authors should carefully study this issue and follow the style of presentation, especially in relation to references and tables. Where relevant, nomenclature and order should follow the latest published for The British List by the British Ornithologist's Union and available on their website at www.bou.org.uk. English names should follow the same list. Contributions should, if possible, be submitted to the editor by e-mail or on a CD/DVD and written in Microsoft Word. If typed, manuscripts should be double-spaced, with wide margins, on one side of the paper only. They must be in the final form for publication: proofs of longer papers are returned to authors, but alterations must be confined to corrections of printer's errors. The cost of any other alterations may be charged to the author. Photographs and line drawings are required to complement each issue. Suitable photographs of birds, preferably taken in Suffolk, can be either digital or in the form of 35mm transparencies. A payment of ÂŁ12 will be made to the photographer for each photograph published and ÂŁ12 for each drawing. Every possible effort will be made to take care of the original photographs and artwork. However, photographers and artists are reminded that neither the editor nor the SNS can be held responsible in the unlikely event that loss or damage occur. Authors may wish to illustrate their papers, but this will be subject to the illustrations being of the standard required by the editor and the decision on such matters will rest with him or her. Material submitted for publication should be sent to the editor no later than March 1st of each year. Authors of main papers may request up to five free copies of the journal. Any opinions expressed in this Report are those of the contributor and are not necessarily those of the Suffolk Naturalists' Society or the Suffolk Ornithologists' Group.

Suffolk Ornithological Records Committee: Chair: Steve Piotrowski Area County Recorders'. Colin Jakes, David Fairhurst (to 31/12/2006), Andrew Green, Eddie Marsh. Secretary. Justin Zantboer Other Committee Members: Will Brame, John Grant, Lee Gregory, Peter Ransome, Brian Small, David Walsh, Robert Wilton, Malcolm Wright.

ADDRESSES Papers, notes, drawings and photographs: The Editor (Suffolk Birds), The Suffolk Naturalists' Society, c/o The Museum, High Street, Ipswich IP1 3QH. Records: See inside front cover. Suffolk Ornithological Records Committee - correspondence: The Secretary, SORC, c/o The Museum, High Street, Ipswich 1P1 3QH.

4


Suffolk Birci Report

2006

Editorial There have been some profound changes in the British avifauna in the lifetime of most of us birding now. Many species have declined in abundance for various reasons and plenty of examples could be given in relation to Suffolk. Just in the past decade the county has lost Whinchat as a breeding species, nesting Common Snipe have ail but gone and a quick count reveals that the populations of more than 20 other species are seriously declining at the present time. This includes species as varied as Turtle Dove and Cuckoo, Sky Lark and Willow Warbler and Spotted Flycatcher and Corn Bunting. The reasons for the losses are varied, but just about ali are down to the activities of that supposedly advanced primate, Homo sapiens. The advent of industrialised farming, with its huge fields of monocultures and large input of herbicides and pesticides, has clearly affected many species over the past 50 years, among them Grey Partridge, Sky Lark and several of the finches and buntings. While populations of some may have stabilised at a lower level others, such as Lapwing, are stili declining. An increase in human population, a big increase in traffic levels and rapid, poorly controlied economie growth are also having an adverse affect. The recent sudden decline of the House Sparrow is stili a mystery, as is the decline of some woodland birds, such as Willow Tit and Lesser Spotted Woodpecker, although a number of possible reasons for the woodland birds' decline have been suggested (British Birds Vol.98 pl 16-143). Some of our summer visitors, e.g. Redstart, Willow Warbler and Spotted Flycatcher, appear to be detrimentally affected by some factor on their migration routes or in their winter quarters. This could be dégradation of habitat where they winter, widespread use of noxious pesticides now banned in this country or climate change affecting wintering areas and/or migration. Not ali the changes have been of a downward direction, although the pluses are far fewer. Who would have thought, twenty years ago, that Little Egrets would colonise the county to the extent that they now outnumber Grey Hérons on our estuaries? As related later in this Report, they can now be found feeding on little brooks and streams and even ditches far inland. The reader of this Report will also find a paper detailing the recent return of the Buzzard as a breeding bird. Buzzards didn't nest in Suffolk (or most of lowland England) from 1875 until 1999, due to persécution by humans, but just seven years later there are about 50 pairs nesting in the county. A run of recent mild winters and perhaps climate change has assisted both Cetti's and Dartford Warblers to colonise and both are currently stili increasing. I have already mentioned climate change twice and this is a factor that could cause further large and unpredictable upheavals in the county's bird populations. The latest reports indicate that changes may be happening even quicker than forecast only a year or two ago. As I write there are reports of record temperatures above 20°C in July 2007 in the Canadian High Arctic (about 15°C above the long terni average!) and massive melting of the Arctic sea ice to the lowest levels ever recorded. The fabled North-west Passage, connecting the Atlantic to the Pacific north of Canada, is temporarily ice-free for the first time in recorded history. From ali of the above, it is clear that we are living in a period of rapid change for our avifauna and we need to document these changes as accurately as possible. This will give the national and local conservation bodies the information they require to influence events and push for change. November 2007 sees the start of the next national BTO Atlas (and Suffolk is planning to compile a more detailed Atlas for the county as well), this time combining both breeding and wintering periods. The four-year project will map the current summer and winter distribution of ali our birds. There were previous Breeding Atlas

5


Suffolk Birci Report

2006

surveys between 1968 and 1972 and 1988 and 1991 and a Winter Atlas survey between 1981 and 1984, so we have a good base with which to compare the results. Everyone can help and all SOG and SNS members with any interest in birds could take on the recording of their local tetrad or 10-kilometre square. Survey work of this kind is enjoyable and you will get a lot out of it. To find out more, visit the website www.birdatlas.net. Please help if you can, as it is really important that the project is successful. The results from this Atlas are likely to provide the basis for the conservation of birds in Britain and Ireland over the next few decades. Mick Wright is the Regional Organiser for Suffolk and you can contact him on 01473 710032 or email micktwright@btinternet.com The Review of the Year, which follows this Editorial, is very brief this year. This is largely in order to fit in the five papers that follow, which were felt to be more important, and we do have limitations of space. All the species are covered in detail in the main systematic list and there is a separate paper on the rare birds that occurred in 2006 later in the Report. 1 have edited the Suffolk Bird Report for five years now and that is long enough; it's time to hand over to someone else with fresh ideas, so this will be my last as editor. It has been enjoyable and stimulating for those years but also quite arduous and time consuming. We need more SOG members to assist with such tasks, in Order to spread the load more, so if you have any talents to offer, please help out. I must thank all those who have helped with this Report and the preceding ones. Foremost is Philip Murphy, who has once again read (he entire systematic list and suggested many amendments and improvements and also advised on other sections. The Report is much better for his careful attention. Adam Gretton has edited the papers and Tony Howe and Trevor Kerridge have arranged the artwork and photographs respectively. Our thanks to all the observers, reserve Wardens and volunteers, WeBS counters; BBS surveyors, the observers at Landguard and Orfordness, bird ringers and others who have sent in the data from which the Report is compiled. Without their efforts there would be nothing to report on. Please continue to submit your reports to the three recorders, who are the lynch pins of the system. The three recorders for 2006 were Dave Fairhurst, Eddie Marsh and Colin Jakes and we must thank them for their sterling efforts. Dave Fairhurst has now handed over to Andrew Green as north-east recorder (see inside front cover for dĂŠtails). Sixteen diffĂŠrent authors have written the systematic list and they are credited at the beginning of that section. The papers have been contributed by Norman Sills, Peter Rock, Peter Dare, Chris Gregory, David Walsh, Adam Gretton and Peter Lack. Brian Small painted the superb Red-flanked Bluetail at Thorpeness, which is on the front cover. Our thanks to the other artists and photographers for letting us use their work; they are credited at the appropriate places. Justin Zantboer, secretary of SORC, was extremely helpful in answering my many queries, other members of SORC also assisted in various ways and David Walsh liaised with regard to BBRC records. Peter Lack helped again to sort out some IT problems and Andrew Gregory has undertaken publicity and distribution of the Report. The weather summary was compiled with the help of Ken Blowers monthly weather review in the EADT. My thanks to my family, who have assisted in various ways and especially Rosemary, who has read the whole Report looking for grammatical and other errors. Mike Gaydon, of Healeys, has once again guided it through the printing process with his usual skill.

6


Suffolk Birci Report

2006

Review of the Year Malcolm

Wright

Weather January was unusually dry and most parts of the county reported only about 12mm (half an inch) of rain. It was generally mild, with no snow, although cold north-easterly winds set in during the second half of the month. The dry theme continued into February and rainfall for the four winter months was well below average. After a mild spell mid-month, very cold north-easterly winds again dominated. These cold winds continued through March, making survey work on the National Wood Lark census very difficult and it was the coldest early spring for 25 years, with a maximum temperature of only 3°C (37°F) on 16th. April was the seventh consecutive month with a rainfall deficit. After a cold and often windy start temperatures were frequently above normal. Following two short warm spells in early May, the long dry spell came to an abrupt end and from mid-month there was rain or showers on most days, with fresh to strong winds. Most parts of Suffolk reported around 100mm (4 inches) of rain for May, more than double the long term average. This cool, wet spell, coming at the height of the breeding season, undoubtedly destroyed many thousands of nests and/or vulnerable pulii throughout the county. After the wettest May for 47 years, June was mostly warm and often dry, with anticyclones controlling the weather and a mini-heatwave from 6th to 12th. July was hot throughout and temperatures in west Suffolk reached 32°C (90°F) on some days. Over a wide swathe of England it was the hottest July for at least 300 years. Thunderstorms developed giving variable but mostly low rainfall. August was as wet, cool and unsettled as July had been hot and dry. In parts of Suffolk it was the wettest August for 50 years and some weather stations recorded over 150mm ( 6 inches) of rain. It was all change again for September, which was one of the four warmest in the past 150 years. It was exceptionally warm early in the month, when temperatures reached 27°C (80°F) in Ipswich on 6th. Rainfall was below average. The fine weather largely continued into October, which was also a very warm month. However, it was also sometimes unsettled, with above average rainfall and some windy days. Heavy rain fell on 23rd/24th, producing widespread flooding. November was mild throughout and the autumn as a whole (September to November) was the warmest for well over 200 years. Rainfall was close to the long-term average. December continued unsettled but mild to the year's end. Overall it was a topsy-turvey year. It had a very dry start but rainfall ended up a little above the long-term average. May and August were dull wet and cool but July, September and October were exceptionally warm. The Breeding Season Perhaps the most remarkable event of the year was the nesting of a pair of Goosander along the Little Ouse River between Barnham and Thetford. This is a considerable southward range extension for this species and the first confirmed nesting record for East Anglia. Two juvenile Garganey were seen at Trimley Marshes in August, although their origins were unclear. There was a total of 23 booming male Bitterns in Suffolk in 2006 and 18 known nesting attempts. This represents two-thirds of all the recorded nesting attempts in Britain. At least four nests failed at Minsmere, due to the poor May weather. Little Egrets continue to spread and are now quite often found on little brooks and streams well inland, as well as being widespread along the coast. At least 34 pairs nested at three

7


Suffolk Birci Report

2006

sites and birds were present at other sites where it was not possible to get counts. Spoonbills built a very large nest at one site but it was subsequently deserted. At least 108 Marsh Harriers were fledged from 48 nests, although this data is known to be incomplete and one pair of Goshawks nested and reared a chick. Buzzards continued to spread and are now well-established in the county. At least 26 pairs bred and there are thought to be 60-70 pairs in total. Hobbies are also thriving; a survey of Thetford Forest (including the Norfolk section) located 23 pairs and 18 young were ringed from seven nests. An additional report for 2005 details the attempted nesting of a pair of Blackwinged Stilts in the county. Plenty of Avocets were present but they suffered another very poor breeding season, with gulls predating all the chicks at the three main colonies. At least 84 pairs of Stone Curlew nested and after a very mild autumn, several wintering birds were recorded. The construction of farm irrigation reservoirs is probably assisting Little Ringed Plovers and three young were fledged from one site. Eleven pairs of Mediterranean Gulls nested at two sites and the 50 or so pairs of Little Terns suffered another poor year, with very few young reared. Turtle Doves continued to decline and the BBS indicates that their population has halved in the past ten years. Although hampered by the poor March weather, the National Wood Lark survey produced a grand total of 370 singing males/territories for Suffolk and the county once again has more Wood Larks than any other in the UK. Black Redstarts are just hanging on as a breeding species, with nesting again occurring within the Sizewell power station complex and probably within Felixstowe Docks. The mild winters are certainly helping Cetti's Warblers, which were numerous on some sites along the coast and are starting to show signs of colonising inland reserves. The same is true for Dartford Warblers, which increased yet again and now number at least 123 pairs/territories. There was no confirmed nesting of Firecrests, but at least nine males were singing or holding territory during the breeding season. Spotted Flycatchers were better reported than usual, with a total of 99 breeding pairs located. In the county's reedbeds, Bearded Tits are doing well, with a population which was almost certainly over 200 pairs in 2006 and included a further increase at Lakenheath Fen to 23 pairs. There were also three pairs of Golden Oriole at the latter site and at least two young were fledged. There were a number of reports of nesting Crossbills, including nine nests located in The King's Forest. The breeding season in 2006 appears to have been a poor one for most of the small passerines and the CES ringing project at Lackford Lakes gives an indication of this. While the number of adults trapped at 131 was close to the five-year average of 139, the number of juveniles trapped was just 136, compared to the five-year average of 232. This is the lowest number ofjuveniles trapped in the 15 years (1992 to 2006) that the project has been run at Lackford. Other sites in Suffolk reported similar results and the main reason seems to have been the spell of cool, wet and windy weather in May. Wrens, Dunnocks, Song Thrushes and Chiffchaffs appear to have been among the species affected. Summary The first winter period was generally mild again, with few hard frosts and little snow. A Ross's Gull was found in Lowestoft Harbour on January 6th, the first record for Suffolk and the bird of the year for many. There were no hard weather movements and a notable event was the first-ever over-wintering of a Whitethroat in Suffolk, near Felixstowe Ferry. Very cold north-easterly winds during late February and March appeared to reduce breeding numbers of some vulnerable species, such as Goldcrest and Long-tailed Tit. This may also have been the reason why many of the summer visitors were late arriving, although a bigger factor was probably a spell of poor weather in the Mediterranean area, particularly Spain.

8


Review of the Year As mentioned above, cold, wet and windy weather during May spoilt the breeding season for many species, but it did produce four unprecedented spring records of Storni Petrel. There were no records of Hoopoe. the first blank year since 1963! The autumn was very warm and often settled, so conditions were rarely favourable for sea-watching. Perhaps the fine weather was responsible for the latest-ever records of Grasshopper Warbier (October 8th), Cuckoo (October 2Ist) and Osprey (December 12th), but there were no Pallas's Warbiers (first blank year since 1992) and there was a late, rather weak passage of Fieldfares and Redwings. Very mild weather continued right to the year's end and led to the first December records of Stone-curlews since 1968.

Grey Heron Donald

9

Simpson


Suffolk Birci Report

2006

Lakenheath Fen - the First Ten Years Norman

Sills

Principles Lakenheath Fen nature reserve was born out of the RSPB's strategy to create large, wet reedbeds, away from the coast, with breeding Bitterns (Botaurus stellaris) as the principal target species. One aim was to replace, or re-create, some of the wetlands which used to exist in The Fens of eastern England until the mid-1600s; 1,300 square miles of wet landscape encircled by King's Lynn, Cambridge, Huntingdon and Peterborough, with a northward extension towards Lincoln. There are some historical descriptions of that landscape. For example, an eighth century monk called Felix wrote t h a t . . . "There is a fen of immense s i z e . . . there are immense marshes, now a black pool of water, now foul running streams, and also many islands, and reeds, and hillocks, and thickets, and with manifold windings wide and long it continues up to the north s e a . . . " . Later, on June 4th 1249, " . . . the sheriff of Cambridge was ordered to buy . . , for the king's use, 12 swans, 12 peacocks, four cranes and as many herons and bitterns as he could get" (Darby 1974). However, the change from "immense marshes" to immense arable was gradual. Even in the 19th century, wildfowl were still caught in large numbers in fenland decoys for the London markets, such as 15,000 in one season prior to 1850, from the Sedge Fen decoy near Lakenheath (Wentworth-Day 1954). It seems that the land now occupied by the reserve was not drained until the mid 1800s and as it was achieved by only ditches and a wind-pump, wet meadows and pockets of marsh persisted until just after the second world war. Montagu's Harriers were still nesting in nearby fens in Norfolk until the mid-1960s (Taylor, Seago et al. 1999). However, the long-term and extensive drainage of The Fens left only a few fragments of that original, vast tract of wetland. Some of these eventually became partly-wooded, such as Wicken Fen, Woodwalton Fen, Holme Fen and Chippenham Fen (totalling 3.5 sq. miles), whereas others remained as extensively-grazed fen such as the Nene Washes and Ouse Washes (totalling 12 sq. miles). A second motive was the awareness that freshwater wetlands near the coast of East Anglia are under threat from sea-level rise. Several "managed-retreat" schemes have either been implemented or are planned (e.g. Cley reserve in north Norfolk) and others may follow at locations such as Minsmere and Titchwell Marsh. The aim is to create new marshes well inland, to act as supplements to those new areas replacing specific losses on the coast. These motives underpinned some of the UK Government's biodiversity plans. The Habitat Action Plan declared that 1,200 hectares of new reedbed - in blocks of not less than 20 hectares - should be created by 2010 and the Species Action Plan for Bittern declared that there should be 50 booming males by the same year (UK BAP 1995). With these strategies in place, the RSPB began their wetland-creation efforts in East Anglia at two sites: Lakenheath Fen in Suffolk and the Hanson-RSPB Wetland Project in Cambridgeshire. The first involved 300 hectares and began in 1995; the second, 600 hectares, from 2003. The process at Lakenheath Fen began by seeking land that was large, flat, peaty and wettable; the first purchase was completed in September 1995, followed by others in 1997. By then, hydraulic excavators were beginning to change the landscape. Processes This change involved a "change of use" as recognised by the district council's planning

10


Lakenheath Feri - the First Ten Years department. The process, necessarily, involved consultation with other authorities, such as Suffolk County Council, regarding the Reservoirs Registration Act; the Environment Agency (water resources); MAFF, now Defra (the movement of soils); Suffolk Archaeological Unit; the MoD (aircraft safety); Lakenheath Internal Drainage Board (interests of adjacent farmers) and Network Rail (effect on adjacent railway embankment). Briefly, it meant that as no soil could be removed from the reserve, most future water-levels would be above natural ground levels; the reserve thus became a reservoir, legally demanding a Safety Bank. Also, outcrops of sand above the peat had archaeological interest, which limited excavation; the risk of large gull roosts (potentially affecting aircraft opérations) limited the size of water bodies and holding high water-levels on porous land next to arable land could adversely affect farming interests. Practicalities To address some of these issues the RSPB commissioned a hydrological study. This resulted in the formation of various infrastructure works: a safety bank 4.2 kilométrés long; a Channel of similar length to intercept seepage water; a one kilométré diversion to an existing IDB main-drain; eight kilomètres of internal banks to retain winter water; ten hectares of mères (but individually not exceeding one hectare) and 25 kilométrés of Channels. The latter two aimed to provide about 20% open water and at least 200 metres per hectare of reed/open-water interface. Relatively minor works included a river-water abstraction pipe, two automatic pumps, 25 water-control sluices and two emergency water-exit pipes. This work was completed in five major phases (each between 20 and 35 hectares) from 1996 to 2000, during which time over 300,000 reeds (seedlings and cuttings) were planted linearly along water-edges. As reed can spread up to six metres per year in wet, peaty soil. the linear fringes alongside Channels and meres have now amalgamated into almost continuous blocks of reed. A survey in autumn 2006 showed that there are now over 60 hectares of reeds, 25 hectares of open water and an average of 406 metres of reed/open-water interface per hectare, all within a 200 hectare area of land that used to be arable. The balance consists of grazing marsh, land to become reedbed and some higher, sandy areas etc. Wildlife's response Birds The first survey of breeding birds was carried out on all of the then-arable land and woodland in 1996. It was repeated every subsequent year up to and including 2006, but only on developing wetland areas. The 1996 survey included only 30 hectares of new reedbed (planted that year) but by 2001 the expanding wetland habitat - reedbed/grazing marsh, etc. - had grown to nearly 200 hectares. The field-work and analysis was done in accordance with the BTO's Common Bird Census, i.e. mapping the territories of mainly singing males during several visits. For most species the minimum and maximum number of territories were established and the mid-point used to quote population data. It is recognised that "territories" do not necessarily equate to "pairs". In 2006 a total of about 1,500 pairs of 30 wetland species bred in the survey area, with additional species in the poplar woods and riverside washland. Selected breeding species in the developing wetland habitat, in approximate order of abundance in 2006 Reed Warbier (about 780 pairs in 2006) Initially about six pairs were confined to narrow reed-fringes on drainage Channels. Nests

11


Suffolk Birci Report

2006

in new reeds were generally first found two years after planting reed-cuttings and three years after planting reed-seedlings. By 2006, in a typical hectare square of reed with channels running through it, there were about ten pairs of nesting Reed Warblers. It was noticed that where reed had been reduced in height by winter Starling roosts, the reed warbler density was less; it was stili available to later-arriving birds, by which time new growth was sufficiently tali. Sedge Warbler (about 150 pairs in 2006) Initially about seven pairs were found alongside drainage channels. The peak population was 174 pairs in 2005. By 2006 many of the areas dominated by non-reed, rank végétation (nettle/thistle/hemlock/willow herb) had become reedbed or reed-fringe, so territories increasingly became located around bank-sides with rank végétation adjacent to reedfringed channels.

Reed Warbler Sedge Warbler Reed Bunting

The Commonest Reedbed Passerine* - No. of Territories 1996 1997 1998 1999 2000 2001 2002 2003 6 2 34 16 110 242 355 406 7 6

3 4

16 18

16 U

60 50

112 67

144 87

141 163

2004 .640

2005 722

2006 780

164 161

174 132

150 135

Reed Bunting (about 135 pairs in 2006) Initially there were about six pairs alongside drainage ditches in the arable land destined to become wetland. In 2003 there were about 160 pairs but, as with Sedge Warbler, a slight decrease followed with a similar shift in territory distribution by 2006, with birds moving to bank-sides or reed-fringed channels/meres in and adjacent to grazing marsh. Since 2003 the reserve has held the largest population, at a single site, in Suffolk (Wright 2004).

Figure l . T h e population changes of three common species, in an area of expanding wetland on former arable land.

12


Lakenheath Feri - the First Ten Years Whitethroat Numbers increased from 10 to 76 pairs in the 11 years from 1996 to 2006. By 2002 the population was 101 pairs followed by a decrease and a shift in territory distribution similar to that for Sedge Warbler and Reed Bunting. Wren Steadily increased from one to about 65 pairs over the 11 years. Territories were found in habitat similar to that of Sedge Warbler but in many cases the vegetation was puré reed with, perhaps, a small area of rank vegetation on higher, and therefore dry, land. Moorhen Increased from nil to about 45 pairs in 2006, with a peak of 53 pairs in 2003. A difficult bird to survey due to its secretive nature. Coot Increased from nil to about 45 pairs in 2006. Now more or less confined to channels fringed with reeds but, in the years prior to reed-fringe amalgamation, many more nested in wet areas dominated by great reed-mace (Typha latifólia) and reed canary grass (Phalaris arundinacea), but destined to become reedbed (eg. a peak of 136 pairs in 2003). Many newly-planted reeds had to be protected with wire-mesh to prevent Coots curtailing their survival. Water Rail The first summer record was in 2001 after which it increased steadily to a mínimum of 30 pairs in 2006. This figure is likely to be a significant underestimate. Bearded Tit First seen in October 1999, but remained as a winter visitor until early 2004. Bred for the first time in 2004 (four pairs) and increased to 11 pairs in 2005. Systematic counts in December 2005 and January 2006 gave a wintering population of 40 to 50 birds. The breeding population in 2006 was 20+ pairs, which is at least 10% of the 150-200 pairs per annum in Suffolk in recent years. In all five development phases, breeding first occurred five or six years after the completion of excavation and reed-planting. An interesting observation was that nests located between 2004 and 2006 were in narrow (3 to 5 metres wide) fringes of reed with almost no reed-litter on the ground; see Sills (2005). As part of another study, 17 and 50 were ringed at one location on the reserve in the summers of 2005 and 2006 respectively, 64% and 88% of which were juveniles (Simón Evans pers. comm.). Grasshopper Warbler There was a steady increase from nil to nine or ten pairs by 2006. Territories are in habitats of tall vegetation on high, sandy ground, which are unlikely to develop into reedbed. Marsh Harrier Since at least the late 1970s (Piotrowski 2003), one or two pairs have regularly bred in reedbeds on the riverside washland. It took generally five to seven years before the first successful nest was built in a new reedbed area, the first being in 2003 (developed in 1998). Nests built any earlier failed to produce young. In 2003 there were three nests on the entire reserve (which produced ten fledglings), followed by six nests in 2004 (14 young), five nests in 2005 (14 again) and seven nests in 2006 (24 young). These totals of young amount to 10-15% of the annual county total of fledged young between 2002 and 2005 inclusive (Wright 2003, 2004, 2005, 2006). Since 2003 there has been an average of 3.1 young fledged per successful nest, which is comparable to many other studies such as that by Sills (1984). Based on measurements at four first-time, successful nests in a new reedbed the birds seem to require an average of 13 metres (mínimum 12) width of reed before reaching

13


Suffolk Birci Report

2006

open ground and an average of ten métrés (minimum eight) width of reed before reaching open water. Some nests were only 300 to 400 métrés apart. Hobby From 1996 to 1999 inclusive, no more than three hobbies were seen in the air at once and most occurred in May/June and August/September. From 2000, peak numbers from early May to mid June increased, with seven that year, 12 in 2002, 25 in 2003, 36 in 2004, 21 in 2005 and 37 in 2006. One pair bred in 2002 and probably 2003, with two pairs in 2004 and three pairs in each of the following two years. Bittern Singles recorded on two dates in 2002 and 2003, nine dates in 2004 and 15 in 2005, the latter including dates between Aprii and August. In 2006 a single bird was seen on seven dates between January and August, plus a maie "booming" daily between early May and mid June. None has ever been seen in September or October. There were two sightings in November/December 2006. The "booming" maie ranged within an area of 18 hectares and the principal site was in a hectare square that had the highest amount of open water and the Iongest reed/water interface on the reserve : 25% and 780 métrés per hectare. Spotted Crake One was calling in early May 2002 and then seen (and heard calling at 02.00hrs) in late June; therefore it probably bred. One was also heard calling in late Aprii, early May and early June 2003, but ail in différent areas. No more than six pairs have bred annually, but irregularly, in Suffolk, (Piotrowski 2003). Cetti's Warbler Although not a confirmed breeding species, the number of dates on which it was recorded increased from one in 2004 to ten in 2005 and 13 in 2006. Ail were heard between October and early Aprii, except in 2006 when singles were also heard in two locations, but on only two dates, in June and July. Birds were heard beyond the ex-arable land (such as Botany Bay SSSI) on a few occasions during the same years, but always in winter. Duck species. Populations are difficult to assess but several broods of Gadwall and Mallard are seen in most years, plus a few broods each of Shovelers and Tufted Ducks. One pair of Shelducks nest in the higher sand-ridges and Garganey may nest either within the developed area or on the river washland. One pair of Ruddy Duck bred in 2003 and 2006. Other species. Peak number of pairs in parenthesis Breeding species that occurred in ail 11 years, were: Mute Swan (13 pairs), Canada Goose (seven pairs) and Skylark (38 pairs). Cuckoos were seen in ail ex-arable areas and, in recent years, often several were present in May/June. The 38 pairs of Skylarks occupied 66 hectares of land that lay fallow (effectively short-term set-aside) in 1997 and 1998, prior to reedbed création. Those nesting in at least one of the earlier years (1996 to 2000 inclusive) were Redlegged Partridge (at least six pairs), Grey Partridge (two pairs), Quail (in two locations), Oystercatcher (two pairs), Little Ringed Piover (one pair), Meadow Pipit (four pairs), Yellow Wagtail (four pairs), Stonechat (one pair) and Corn Bunting (four pairs). Species nesting in nearly ali of the latter six years (2001 to 2006 inclusive) were: Little Grebe (six pairs), Great Crested Grebe (four pairs), Greylag Goose (five pairs), Lapwing (13 pairs, in wet areas destined to become reedbed) and Redshank (nine pairs, in similar areas to Lapwing).

14


Lakenheath

Feri - the First Ten Years

Great Crested Grebes Peter

Beeson

Species not breeding but which occurred between 1996 and 2006 (either as a new species or in larger numbers than previously) and linked to wetland habitats for one purpose or another were: Cormorant, Cattle Egret, Little Egret, Grey Heron, Whooper Swan, Bewick's Swan, Goldeneye, Smew, Montagu's Harrier, Osprey, Peregrine, Black-winged Stilt, Turnstone, Wood, Green and Common Sandpipers, Spotted Redshank, Greenshank, Curlew, Whimbrel, Snipe, Jack Snipe, Red-necked Phalarope, Black-headed Gull, Common Tern, Swift, Kingfisher, Sand Martin, Pied Wagtail, Marsh Warbler and Starling. Other species - breeding and non-breeding - occurred in the poplar woods and river washland, so the species mentioned above do not constitute the full range of species found on the reserve. Other wildlife Perhaps the most conspicuous change resulting from the arable-to-wetland conversiรณn was the emergence of fenland plants. The soil on almost all of the reserve is peat; it was formed from the ancient sedge and reedbeds and during its history it has been deeply flooded, grazed, mown, surface-drained, covered with poplars, deep-drained, ploughed and sprayed with pesticides. Therefore it was something of a surprise when excavations + water + sunlight promoted the growth of over 100 species of aquatic/marginal plants. A frequencysurvey was carried out on the ex-arable land in 2001 (and on the adjacent Botany Bay SSSI in 2002) based on presence/absence in 261 hectare squares (Sills and Leadsom 2005). It showed that hemp agrimony (Eupatorium cannabinum), great willow herb (Epilobium hirsutum), purple loosestrife (Lythrum salicaria) and willows (Salix spp) all exceeded 75% frequency, whereas several species were found in only one square. The most notable species were whorled water milfoil (Myriophyllum verticillatum), fen pondweed (Potamogetรณn coloratus) and several other pondweeds. Knotted pearlwort (Sagina nodosa)

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Suffolk Birci Report

2006

was found on a small patch of damp sand. Perhaps the most attractive was water violet (Hottonia palustris), found in 8% of the squares and gradually spreading. There are other examples of 'special' species. Marsh carpet moth, Roesel's bush cricket, red-eyed damselfly, water vole and otter have all occurred for the first time or in larger numbers since the reserve was created. With these, and all the birds and plants, it is easy to demonstrate that an amazing array of wildlife can emanate from, or be attracted to, an area of land that has been changed back to something resembling the "immense marsh" of long ago. References Darby, H.C. 1974. The Medieval Fenland. David & Charles. Piotrowski, S.U. 2003. The Birds of Suffolk Christopher Helm, London. Sills, N. 2005. The Return of Nesting Bearded Tits to the West Suffolk Fens. Suffolk Birds 54: 35-37. Sills, N. 1984. Marsh Harriers at Titchwell Marsh Reserve. Norfolk Bird Report 1984. Sills, N. and Leadsom, S. 2005. The Distribution of Aquatic Plants at Lakenheath Fen Reserve. RSPB report. Taylor, Seago et al. 1999. The Birds of Norfolk. Pica Press, Sussex. IJK BAP 1995. The UK Steering Group Report. HMSO. London Wentworth-Day, J. 1954. A History of the Fens. George G.Harrop, London. Wright, M (Ed). 2003. The 2002 Suffolk Bird Report, Suffolk Birds 52. Wright, M (Ed). 2004. The 2003 Suffolk Bird Report, Suffolk Birds 53. Wright, M (Ed). 2005. The 2004 Suffolk Bird Report, Suffolk Birds 54. Wright, M (Ed). 2006. The 2005 Suffolk Bird Report, Suffolk Birds 55.

Lapwings Donald

16

Simpson


Suffolk Birci Report

2006

Roof-nesting Gulls at the Port of Felixstowe 2001-2006 Peter Rock Introduction Roof-nesting by the large gulls was almost unknown prior to the Second World War. There were occasional records of gulls nesting on rooftops before 1940 and some further, relatively minor colonisation, mostly in coastal towns, between then and the mid-1960's was noted (Parslow 1967). However, it was not until Operation Seafarer (1969-70) that significant numbers of urban sites were identified (60), where Herring Gulls Larus argentatus and Lesser Black-backed Gulls L. fuscus were breeding (Cramp 1971). Traditional gull colonies also expanded rapidly during the period between 1953 and 1972 (e.g. Spaans 1971). This growth was partly aided by decreases in persecution (e.g. Pons & Yesou 1997), but in Britain, in particular, was fuelled by massive food availability - mostly from landfills (Parslow 1967). The Clean Air Act (1956) was a critical factor in population growth, in that the old practice of burning waste at tips was halted and tip faces were required to be covered with inert material (Rock 2005a). The large gulls, always opportunistic feeders (Cramp & Simmons 1983), were quick to take advantage and, with ample food, bred so successfully that traditional colonies were outgrown (Rock 2005a). However, it was not until the 1960s and early 1970s that many of today's larger colonies were established. The 1976 survey (Monaghan & Coulson 1977) revealed 3291 pairs nesting on buildings in Britain & Ireland and by 1994, this figure had grown to 13591 pairs of the two species (Raven & Coulson 1997). Neither survey included data from Suffolk, but Seabird 2000 (1999-2002) reported that 1149 pairs of Lesser Black-backed Gulls and 421 pairs of Herring Gulls were breeding at three urban colonies in the county (Mitchell 2004). It is assumed, therefore, that Suffolk rooftops were first colonised at some point in the 1990s. The Port of Felixstowe The Port of Felixstowe was first visited in July 2000 at the request of the Port Facilities Department after four years of perceived problems with gulls in the port area (aggression towards port staff and damage to warehousing resulting in financial losses, etc). Though 1996, therefore, might appear to be the start date, it is more likely that the port was first colonised some time before the first complaints. This is because early colonisation with just a few pairs often goes unnoticed (Rock 2003). The 2000 provisional estimate was 300-500 pairs (Rock 2000), because the timing of the visit (July) was too late to make more accurate assessments. Annual surveys since then have taken place in the second week of May. 2001 Herring Gull Lesser B.B. Gull Great B.B. Gull Total Pairs

225 192

1 418

Large Gulls - Number of Pairs 2001-2006 2004 2002 2003

2005

2006

1

334 550 3

349 675 3

451 1012 4

628

887

1027

1467

317 250 2

313 314

569

Table 1. Colony Development at the Port of Felixstowe 2001-2006 Great Black-backed Gulls L. marinus were first noted breeding at the Port of Felixstowe in 2001 (one pair). Piotrowski (2003) details successful breeding (one fledgling) on

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Suffolk B i r c i Report

2006

O r f o r d n e s s in 2000. T h e two pairs at the Port of Felixstowe in 2001 are believed to be the second and third successful breeding records of this species in Suffolk. In 2 0 0 6 there were f o u r pairs ( R o c k 2006a), but this species has played an insignificant role in the colony d e v e l o p m e n t at the Port. In 2001 H e r r i n g Gulls o u t n u m b e r e d Lesser Black-backed Gulls by a f a c t o r of 1.2:1, but b y 2 0 0 6 the species split had changed dramatically to a point where Lesser Black-backed Gulls o u t n u m b e r e d H e r r i n g Gulls by a factor of 2.5:1. Colonial Development at the Port of Felixstowe 2001-2006 1200,———

80%

ü Herring Gull

1000-

70%

a Lesser Black-backed Gull

60% 800

50% 40%

600

30% 40020%

10% 0% 2001

2002

2003

2004

2005

2006

Figure 1. Colonial d e v e l o p m e n t ( H e r r i n g and Lesser B l a c k - b a c k e d Gulls) at the Port of Felixstowe 2001-2006. T h e Port of Felixstowe has seen an unprecedented rate of increase in n u m b e r s of b r e e d i n g pairs in the f i v e years 2 0 0 1 - 2 0 0 6 . T h e colony of large gulls in the city of Gloucester, for example, increased f r o m 1345 pairs in 2 0 0 2 (Rock 2 0 0 2 ) to 2478 pairs in 2 0 0 6 ( R o c k 2006b). R e q u i r i n g only a f u r t h e r 212 pairs in 2007, it is anticipated that the Gloucester population will have doubled in five years. T h e expected annual rate of increase in n u m b e r s of urban gulls is 17.6% (Rock 2005a), but the Port of Felixstowe has experienced a m e a n , annual rate of 2 9 . 2 % and the colony doubled in size after only three years. A n n u a l increases in urban colonies are dictated by b r e e d i n g success in previous years, between-year survival rates of both adult and immature birds, ample, suitable and available b r e e d i n g roofs and, most importantly, a f o o d supply sufficient to enable s u c c e s s f u l breeding. N u m b e r s of philopatric, male, first-time breeders are generally m a t c h e d by i m m i g r a n t f e m a l e s f r o m o t h e r colonies ( R o c k 2005a). A n n u a l increases in the Port of Felixstowe population, however, have not been even (range = 9 . 4 % to 4 2 . 8 % ) , but, instead, are characterised b y dramatic swings which can only be explained by erratic, large influxes of birds f r o m other colonies. T h e O r f o r d n e s s colony fell f r o m a high of 2 4 5 0 0 pairs in 1998 (Piotrowski 2 0 0 3 ) to c a . 5 0 0 0 pairs in 2 0 0 5 ( M . M a r s h pers. c o m m . ) , due mainly to fox Vulpes vulpes predation. O r f o r d n e s s is t h e r e f o r e a failing colony. A n o t h e r is Tarnbrook Fell in Lancashire (Sowter 2 0 0 4 ) where persistent culling has reduced n u m b e r s significantly. It appears to be the case that breeding failures in wild colonies result in birds relocating and there is s o m e e v i d e n c e

18


Roof-nesting

Gulls at the Port of Felixstowe

2001-2006

that they relocate to urban colonies which, for the most part, are very successful (Rock 2006c). Two birds from Orfordness have been recorded breeding in the urban colonies in Worcester (Rock 2004) and Gloucester (Rock 2006b) and birds from Tarnbrook Fell have been recorded in Gloucester (Rock 2005b) and Cardiff (Rock 2005c). Felixstowe Population 2001-2006 • 45% • 40%

1400--

• 35%

1 200- -

- • 30%

1000-

-• 25% 800--

• 20%

1 5%

10%

2002

2004

2003

2005

2006

Figure 2. Population growth at the Port of Felixstowe 2001-2006 with annual percentage increases. Some 2800 nestlings have been colour-ringed at Orfordness since 1996 using red rings showing a three-letter code in white (which many Suffolk birders will certainly know). One part of the survey work is to locate and identify colour-ringed birds in order to establish origins. To date (February 2007), apart from gulls colour-ringed at the port and one bird hatched near Rotterdam (which bred at the port in 2001 and 2002), all colour-ringed birds of known origin observed at the Port of Felixstowe have come from Orfordness (51 records of 38 colour-ringed birds).

Records New Individuals Annual % Increase Colony Size (pairs)

2001 t I 418

2002 3 3 36,5% 569

2003 5 5 9.4% 628

2004 1) 9 41.3% 887

2005 9 4 15.8% 1027

2006

22 16 42.8% )467

Totals/Mean 51 38 29.2%

Table 2. Records and numbers of new individuals colour-ringed at Orfordness breeding at the Port of Felixstowe 2001-2006 with annual percentage increases over the same period. As the Port of Felixstowe colony grew (i.e. became more successful), it attracted increasing numbers of recruits from Orfordness (and, almost certainly, from other urban colonies in the region such as Ipswich, Lowestoft, etc.). Of considerable interest, however, is that of 16 new individuals noted in 2006, all were adults, but 12 were six years old or older, strongly suggesting that they had already started breeding elsewhere - probably at Orfordness - and have relocated. In the Severn Estuary area less than 0.5% of birds hatched in urban colonies recruit into wild colonies (Rock 2006c) and from records of colour-ringed individuals in various urban

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Suffolk Birci Report

2006

colonies noted during surveys, it would appear that the rate of recruitment from wild to urban may be equally low (pers.obs.). No urban colonies in the region have more than five breeding wild-ringed birds (most have none) and even Cardiff (which is just 12 km from the wild colony of Flat Holm) has only four (Rock 2006d). That the Port of Felixstowe has 38 is highly significant. In a small way, the increasing numbers of Orfordness-ringed birds breeding at the Port of Felixstowe reflects the failure of the former and the success of the latter. The Future If the Port of Felixstowe's mean, annual rate of increase of 29.2% is cumulatively projected to 2016, the result is a population of 19000 pairs! However, as has been shown, the port's very high annual rate of increase is due (for the most part) to large influxes of Orfordnesshatched birds. With a population now standing at just 5000 pairs, it is considered unlikely that Orfordness will continue to supply new recruits at this level. At a rate of increase of 17.6%, the calculation results in a population of 7400 pairs by 2016. In order to reach this size, immigration from Orfordness would need only to be a fraction of that observed to date, but there are other factors to consider. No firm assessments have been made at the urban colonies in Ipswich and Lowestoft (and other places?), but it is suspected that gull numbers in these colonies have risen (S.Piotrowski pers.comm.), possibly rather rapidly. Successful breeding at these colonies will generate large numbers of potential recruits (e.g. a population of 1000 pairs should produce ca.1000 first-time breeders after three years). Third-summer birds breed commonly in urban colonies (Rock 2005a) and this is a sure sign that colonies are increasing. It is therefore suggested that other Suffolk urban colonies are now in urgent need of assessment, not least because as urban colonies grow, so do complaints to local authorities. Bath, for instance, with a population of 659 pairs (Rock 2006e) receives more than 100 complaints every year (S. Harwood pers.comm.). In Suffolk there have been several references in local newspapers concerning problems with gulls nesting on roofs in Aldeburgh, e.g. an article on page 22 of the East Anglian Daily Times of March 3rd 2007 refers to a proposal to replace gulls' eggs at Aldeburgh with dummy eggs - plastic eggs partly filled with sand. With the proposed expansion at the Port of Felixstowe and the consequent demolition of older, redundant structures, many of the key breeding roofs on port property will disappear to make way for hard-standing to accommodate containers. This will certainly have a significant effect on breeding numbers at the port. As an example, in 2005 the Cardiff population stood at 3475 pairs but in 2006 this reduced to 2899 (Rock 2006d). The primary cause of this reduction (the only reduction ever observed) was significant between-years' redevelopment (demolition) and long-term roof maintenance. However, in the last three years, roofs previously thinly populated or uncolonised at the Port of Felixstowe have seen very large increases in numbers of breeding pairs - and many of them are outside the port's area of jurisdiction. The town of Felixstowe has been incidentally monitored during annual survey work and, as of 2006, there has been no evidence of roof-nesting, but experience from assessments at other urban colonies in the Severn Estuary area suggests that there are ample, suitable roofs available. Therefore, it is possible that as the port's gull population increases, there may be a spread into the town of Felixstowe in the coming years. Acknowledgements I am extremely grateful to Mike Marsh and Steve Piotrowski for all sorts of help over the years. I also thank Port of Felixstowe staff for facilitating surveys, but especially Iain Radford, and Jason and Ashley Buckle. Particular thanks go to Roland Barbrook for

20


Roof-nesting

Gulls at the Port of Felixstowe

2001-2006

unstinting help, profound knowledge of the port and good company during every survey since 2000 - I wish him a long and happy retirement. References Cramp, S. 1971. Gulls nesting on buildings in Britain and Ireland. British Birds 64: 476487. Cramp, S. & Simmons, K.E.L. (BWP) 1983. Birds of the Western Palearctic Volume 3, Waders to Gulls. Oxford University Press, Oxford. Mitchell, I.P., Newton, S.F., Ratcliffe, N. & Dunn, T.E. 2004. Seabird Populations of Britain & Ireland. T. & A.D. Poyser, London. Monaghan, P. & Coulson, J.C. 1977. The Status of Large Gulls Nesting on Buildings. Bird Study 24-2: 89-104. Parslow, J.L.F. 1967. Changes in status among breeding birds in Britain and Ireland: part 3. British Birds 60: 177-202. Piotrowski, S. 2003. The Birds of Suffolk. Christopher Helm, London. Pons, J-M. & Yesou, P. in Hagemeijer & Blair. 1997. The EBCC Atlas of European Breeding Birds. T. & A.D. Poyser, London: 336-337. Raven, S.J. & Coulson, J.C. 1997. The distribution and abundance of Larus Gulls nesting on buildings in Britain and Ireland. Bird Study 44:13-34. Rock, P. 2000. Roof-nesting Gulls at the Port of Felixstowe. Preliminary survey of breeding gulls. Report to Facilities Department of the Port of Felixstowe. Rock, P. 2002. Roof-Nesting Gulls in Gloucester. Survey conducted in May 2002. Report to Gloucester City Council. Rock, P. 2003. Birds of a Feather. Environmental Health Journal May 2003, 132-135. Rock, P. 2004. Roof-Nesting Gulls in Worcester. Follow-up Survey conducted in May 2004. Report to Worcester City Council. Rock, P. 2005a. Urban Gulls: problems and solutions. British Birds 98: 338-355. Rock, P. 2005b. Roof-Nesting Gulls in Gloucester. Follow-up Survey summarising surveys from 2002-2005. Report to Gloucester City Council. Rock, P. 2005c. Roof-Nesting Gulls in Cardiff. Follow-up Survey conducted in May 2005. Report to Cardiff County Council. Rock, P. 2006a. Roof-Nesting Gulls at the Port of Felixstowe. Follow-up Survey conducted in May 2006 and summarising surveys from 2000-2005. Report to the Facilities Department of the Port of Felixstowe. Rock, P. 2006b. Roof-Nesting Gulls in Gloucester. Follow-up Survey summarising surveys from 2002-2006. Report to Gloucester City Council. Rock, P. 2006c. A study to discover the overwintering rate of urban Lesser Black-backed Gulls within a radius of circa 100 km of Bristol. Report to various sponsors. Rock, P. 2006d. Roof-Nesting Gulls in Cardiff. Follow-up Survey conducted in May 2006. Report to Cardiff County Council. Rock, P. 2006e. Roof-Nesting Gulls in Bath. Follow-up Survey conducted in April 2006 and summarising surveys from 1995. Report to Bath & North-East Somerset District Council. Sowter, D. 2004. The Tarnbrook Fell gullery report 2004. Report to UUPLC and Abbeystead Estate. Spaans, A.L. 1971. On the feeding ecology of the Herring Gull Larus argentatus in the northern part of The Netherlands. Ardea 59: 73-188. Peter Rock, 7 Parkside Avenue, Winterbourne,

21

Bristol, BS36 1LU


Suffolk Birci Report

2006

The Return of the Buzzard to Suffolk Chris

Gregory

Once common and widespread across Britain, the Buzzard has suffered both directly and indirectly at the hands of Man for many years. These prolonged periods of human persecution greatly reduced the Buzzard's population and eventually restricted its range to the uplands and valleys of north and west Britain. However, this resilient species steadily expanded its range in the latter part of the 20th century, recolonising many central and eastern areas, including East Anglia. Early in the 21st century it now breeds in every county in Britain and is set to become the commonest raptor species in Britain. Status in the UK In early times the Buzzard was much maligned for its reputation for preying on poultry and livestock, and was widely regarded as a slovenly, cowardly bird. Forest clearance, the spread of agriculture and gamekeeping activities all contributed to a gradual decline in numbers over the years. However, it was wide-scale human persecution during the Middle Ages that had the most serious impact. This was largely due to the introduction of two detrimental Acts. The first of these was introduced in the 15th century by James II of Scotland, who declared the Buzzard as vermin. In the following century, Henry VIII outlawed the theft of birds' eggs, but excluding the Buzzard from the list of protected species. Then, during the 19th century, game shooting became more and more popular and all birds of prey were killed indiscriminately. The level of persecution that followed was so severe that, by the end of the 19th century, the breeding population had become entirely restricted to northern and western Britain, and was reduced to it's lowest ever level. The situation started to improve in the early part of the 20th century, when there was a marked increase in the Buzzard's range eastward across England. This coincided with the onset of World War 1, when many gamekeepers left the countryside to serve their country. The expansion continued at a reduced rate through the 1920s and 1930s, and then accelerated again during the Second World War. In the post-war period, the Buzzard benefited from a reduction in persecution, as there was more of an emphasis on food production and a scaling down of game-rearing on shooting estates. Social and economic changes in the countryside meant that people began to have a more balanced attitude towards wildlife, and improved legal protection was introduced for many species. The 1930s saw a further significant range expansion in the southwest, and by 1954 the Buzzard was breeding in low densities as far as the east Midlands and East Sussex. An estimated total for the UK population at this time was 12000 breeding pairs. The species faced more adversity after 1953, when myxomatosis arrived in Britain, wiping out 99% of the rabbit population within three years. Inevitably the loss of such an important prey item had a severe impact on Buzzard numbers. Fortunately, having a catholic diet ensured its survival and numbers had started to recover by the late 1950s. However, this recovery was checked in the mid-1960s, when the cumulative effects of organochlorine pesticides in the foodchain started to emerge. The chemicals caused the thinning of eggshells in birds of prey, particularly in bird-eating raptors. Although the Buzzard was not as badly affected as other species, the British breeding population fell to the post-myxomatosis levels of 8000 to 10000 pairs. Concern about the effects of these pesticides on the environment led to a ban of many chemicals in 1962 and finally, to a total ban four years later. Since then the Buzzard population has been steadily increasing and by 1983 there were 12000 to 17000 pairs holding territory in the UK.

22


The Return of the Buzzard to Suffolk British Trust for Ornithology surveys covering the last 40 years show a graduai rise in the UK population over the first 20 years, followed by a marked increase from the 1990s. This increasing trend was identified by the Common Bird Census, which revealed the range expansion into central and eastern Britain, where there was more CBC coverage. The introduction of the Breeding Bird Survey in 1994 provided more geographically reprÊsentative data on the expansion and suggested that between 1994 and 2003 Buzzard numbers rose by 50%. The most marked increases were in England and Scotland (56% and 81% respectively), whereas in Wales, where there was already a healthy population, the rise was more modest (5%). In 2000, the estimated total number of territorial pairs in the UK was 31000 to 44000 (BTO figures based on the 1988-1991 Breeding Bird Atlas results updated using CBC/ BBS trend). More recent estimâtes put the figure at 44000 to 61000 (Clements 2002) and there are prÊdictions that the population could reach 100000 pairs in the UK. Ringing recoveries and radio tracking results have provided valuable d u e s as to how this dramatic expansion may have occurred. Although Buzzards are essentially sedentary, data has shown that about 50% of young birds disperse from their natal areas in their first autumn. Radio-tagging suggests that the first birds to leave large broods tend to move longer distances. Also, that there is a tendency for immature birds to move east from their breeding sites, a feature that became more significant in second calendar-year birds.

Year Some areas of south-east England have experienced increases of 400% in the last decade. In East Anglia the increase is nearer 800%, with the number of pairs holding territory increasing from 12 in 1999 to an estimated total in excess of 100 in 2005. In Suffolk the number of territorial pairs increased from three in 2000 to a minimum of 28 in 2005. In Norfolk, where there was a fairly small but stable population in the early 1990s, numbers increased dramatically from the turn of the Century and now stand at almost 50 territorial pairs. An ITE scheme was responsible for the release of five birds in Norfolk in 1994, and a further eight birds in 1995. It is not known what effect, if any, the released birds had on the recolonisation by this species in Norfolk or Suffolk. It was a similar story

23


Suffolk Birci Report

2006

in Cambridgeshire and Essex, where the number of pairs quadrupled from four in 2001 to 17 in 2004 and from five pairs in 2000 to 19 pairs in 2004, respectively. Historical Status of the Buzzard in Suffolk It is unclear just how abundant the Buzzard was in Suffolk in early times. The landscape was irreversibly altered from the time when Neolithic man cleared much of the ancient woodland, though many woods on the heavier soils survived at least until the Bronze Age. By the end of the l l t h century woodland covered less than 10% of the county and it is likely the Buzzard population had already declined. In his book 'Birds Of Suffolk' Ticehurst stated he was in little doubt that the Buzzard formerly bred in Suffolk woodlands on a regular basis, but was probably never abundant. Babington described it as rare in many areas during the 19th century, though its numbers fluctuated from year to year. It is likely that the Buzzard had a fairly stable, if restricted, population in Suffolk, at least until the 16th century. Most landowners probably tolerated losing the odd chicken or lamb, so for many years any persécution was probably fairly low-key and unco-ordinated. However, that situation changed in the 15th century, when the commercial production of rabbits became a major industry. Originally introduced in the 13th century, the rabbit took decades to acclimatise to the English chinate. The sandy soils of Breckland held the largest concentration of warrens in Britain, employing hundreds of "warreners", whose job it was to tend the rabbits. At its peak, the industry supplied rabbit meat for Royal banquets and rabbit fur for hat making and few parts of the animal were wasted. Described by some as "a great destroyer of conies", the Buzzard was considered a real threat to the rabbit industry, so was listed as "vermynne" under the Act of 1566. Such vermin acts were widely implemented in the 16th and 17th centuries and people risked being fined for failing to control vermin on their land. Though widespread, the levels of persécution varied greatly from district to district. Some local churchwardens' accounts bear testament to the onslaught that ensued between the 16th and 18th centuries and it is likely that the Buzzard was completely eradicated in many Suffolk parishes during this period. The Cratfield Parish Accounts of 1580 refer to a "John Newson" being paid for two Buzzard heads, and in 1568 at Bedingfield one shilling was paid for one Buzzard head. It was not just Buzzards that were targeted; Red Kites and other species also had a premium on their heads. Ironically, one inévitable side effect of the extermination of so many naturai predators was the increase in the numbers of other vermin, such as rats. Ticehurst wisely observed "there is little doubt that one pair of rats and their progeny would do far more harm in the course of a year than a pair of Buzzards and their young". The campaign finally ended in the 18th century, probably because there were so few birds of prey left and because churchwardens became increasingly occupied with controlling House Sparrows and Rooks, whose populations had rocketed. However, there was no respite for the Buzzard, as shooting was fast becoming a popular pastime on many country estâtes. Gamebirds were reared on a massive scale to meet the demand and gamekeepers were given carte blanche to embark on a systematic destruction of ail birds of prey. It was this relentless persécution which resulted in the loss of the Buzzard as a breeding bird in Suffolk by the end of the 19th century. Ticehurst commented "Little wonder that this fine bird has died out as a nesting species; every gamekeeper's hand was against it; no one seems to have given it any sanctuary". Babington documented just a handful of breeding records during the 19th century, including a family party at Great Barton in 1835 and the removal of three eggs from a nest high in a Scots fir at Tostock in 1852. He also gave an account of a particularly brutal incident he witnessed on one nesting

24


The Return of the Buzzard to Suffolk pair of Buzzards near Felsham in 1874, where the gamekeeper had killed one of the adults and thrown it to foxes. Amazingly, a pair returned the following year, only for the iemale to be "wounded" on the nest. The Babington incident was the last proven record of breeding in Suffolk prior to recent events, although a group of five birds near Brandon in 1922 may have been indicative of breeding. More pressure carne in the Victorian era when the collecting of skins and eggs became fashionable. Despite new législation being introduced to help protect birds of prey, it was difficult to enforce. Persécution levels did drop during the two World Wars, when many gamekeepers went off to fight, but the Buzzard continued to be recorded primarily as a winter visitor and passage migrant in Suffolk. Results of a survey in 1954 provided strong evidence that gamekeeping activities continued to hamper the re-establishment of the Buzzard in our région. The distribution of gamekeepers in Suffolk was one of the densest in Britain (three to six per 100 square miles). Elsewhere in the country, where there were fewer keepers, there was an increase in the Buzzard's breeding range. During the 1960s and 1970s, there were occasionai reports of single birds in Suffolk and, less frequently, pairs in the summer months. Gamekeepers were stili considered by many to be a threat; a suspicion backed up by further survey results which clearly showed that the large gaps in the species' distribution stili coincided with some of the larger estâtes in the county. Paine refers to one incident near Icklingham in 1975, where a Buzzard seen hunting rabbits (now firmly established as a pest species) soon became the target of a locai gamekeeper. The status of the Buzzard in Suffolk changed very little during the 1980s. There was some optimism when a bird was seen carrying food in 1988, but there were no subsequent sightings. It was not until the 1990s that there were real indications that the species was attempting to re-establish itself as a breeding bird in the county. Reports of summering birds increased in the 1990s, as did reports of long-staying individuáis, some remaining at the same site ali year. In 1995 there were 150 reports from 50 parishes across Suffolk, but despite rumours that one or two pairs were holding territory, there was no hard evidence of breeding. This may have been due to reluctance by birdwatchers to give out information about potential nesting birds, which is quite understandable given the history of persécution of this species. By the mid-1990s re-colonisation had started to gain momentum in Suffolk. The first indications of breeding eventually came in 1998, when a pair was suspected to have nested in the north-east of the county. Breeding was finally confirmed the following year, at a site near Newmarket, where a pair successfully raised two young and became the first confirmed breeding pair in the county since 1874. The pair bred successfully at the same site again in 2000, this time raising three young. Displaying birds were reported at three sites in north-east Suffolk and birds were also seen at several other sites across the county during the summer. By 2003 a minimum of six pairs were breeding in the west, with at least four more holding territories elsewhere in the county. The following year the number of territorial pairs in the Brecks had increased to a minimum of 14 and a further four pairs were holding territory in the south-east, where one pair bred successfully. In 2005, almost 30 pairs were present in the county and at least 15 of these bred. In 2006, this number had risen to between 48 and 52 territorial pairs and about half of these was confirmed to have nested. These figures do not just reflect an increase in population, but also an increase in the number of people reporting Buzzards. Perhaps this is a reflection of the fact that the threat of human persécution is diminishing.

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2006

Population modelling shows that the relatively small proportion of Buzzards deliberately killed by Man in southern Britain is well below the level that might hinder population expansion. At a regional level, such incidents are quite rare and there has been just one reported case of Buzzard persecution in Suffolk in the last five years. It is also clear that there has been a shift in attitude by an increasing number of estate owners and gamekeepers. Buzzards are now breeding successfully on several large estates in Suffolk, including the Elveden Estate in Breckland, the Benacre Estate on the east coast, and the Freston Estate on the Shotley peninsular. Another recent example of this more tolerant approach involved a farmer who was actively encouraging a pair of Buzzards, at a site near Stoke-by-Nayland, by providing them with shot rabbits. The re-colonisation of Suffolk by this species has been nothing less than emphatic. Even a decade ago, few would have predicted that the Buzzard would be gracing the skies in so many areas of the county. It is also heartening that the two key factors in the Buzzard's expansion, suitable breeding sites and abundant prey, still occur in our region. Possible factors which could limit this continued spread include the ongoing threat of a crash in the rabbit population through disease and the saturation of suitable breeding sites as more and more optimum habitats are occupied. We also have to hope there is no resurgence of antipredator feeling amongst landowners and gamekeepers towards the Buzzard as it is encountered on a more regular basis. Acknowledgements My thanks to Andrew Green, Adam Gretton, Nick Mason, Rod Plowman and Mick Wright for help in various ways. References Babington, Rev. Dr C. 1884-1886. Catalogue of the Birds of Suffolk. John Van Voorst. London. Cambridge Bird Report. 1997-2005. Clements, R. 2002. The Common Buzzard in Britain: a new population estimate. British Birds 95: 377-383. Gibbons, D.W., Reid, J.B. and Chapman, R.A. 1993. The New Atlas of Breeding Birds in Britain and Ireland. T & A.D.Poyser. London. Martin, B.P. 1992. Birds of Prey of the British Isles. David & Charles. Devon. Newton. I. 1979. Population Ecology of Raptors. T & A.D. Poyser. Berkhamsted. Norfolk Bird & Mammal Report. 1997-2005. Paine, A.R.J. 1979. Birds of Prey in Suffolk 1973-1978. SOG Report. Piotrowski, S. 2003. Birds Of Suffolk. Christopher Helm. London. Rackham, O. 1986. The History of the Countryside. J.M. Dent. London. R.S.P.B. 2006. Birdcrime 2005. Sharrock, J.T.R. 1976. The Atlas of Breeding Birds in Britain and Ireland. T & A.D. Poyser. Suffolk Bird Report. 1990-2005. Suffolk Naturalists ' Society. Ipswich. Ticehurst, C.B. 1932. History of the Birds of Suffolk. Gurney and Jackson. London. Tubbs, C. 1974. The Buzzard. David & Charles Ltd. Devon. Wright. M. T. 1998. Survey of Breeding Raptors and Owls in Suffolk 1995-1998. Wernham, C., Toms, M., Marchant, J.H., Clark, J., Siriwardena, G. and Baillie, S. 2002. The Migration Atlas. T. and A.D. Poyser. London.

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Spring Movements of Common Buzzards along the Suffolk Coast Peter DarĂŠ Introduction In coastal north Suffolk, from around the Alde Estuary to north of Lowestoft, the sight of Common Buzzards Buteo buteo passing over in early spring has become a keenly anticipated and almost familiar event for raptor enthusiasts since the mid 1990s. The annual sightings listed in Suffolk Birds Reports (SBRs) show that prominent spring movements began in 1995 (Piotrowski (2003), as happened also along the Norfolk coast (NBRs), though the upsurge in records could partly have reflected increases in observer awareness and activity. There is no evidence of a comparable status change in the Suffolk hinterland, though this larger regiĂłn is under-watched, except around the Breck. Historically, this fine raptor was resident in both counties until it was exterminated as a breeding species by game-keepers and collectors. The last pair nested in Suffolk in the late 19th century (Piotrowski 2003); a pattern repeated throughout lowland England. From 1900 until the 1990s, the Buzzard's status had long been described mainly as a passage migrant in coastal localities, with a few birds over-wintering in both Suffolk and Norfolk (Piotrowski 2003, Taylor et al., 1999). Happily for present day bird-watchers, however, Buzzards are now returning to East Anglia woodlands as a result of greatly diminished persecution in this more enlightened and conservation conscious era. Over the last 20 years, Buzzards have been spreading back from west-country refuges and at an increasing rate of recolonisation (Clements 2000). A few pairs became re-established in Suffolk Breckland forests from 1991 onwards and several pairs have nested in south Suffolk since 2004 (SBRs) while 2-3 pairs bred in north-east Suffolk in 2006 with 4-5 pairs there in 2007 (pers.obs.). In Norfolk, the surprise appearance and successful breeding of a pair (of uncertain origin) in 1992 was followed by an oĂ­ficial release scheme during the mid 1990s (Taylor et al., 1999). From that start, Buzzards have bred successfully every year and spread in Norfolk. By 2005 the expanding population had reached 25-47 pairs and these reared at least 42 fledglings that year (NBR). In north-east Suffolk, I kept a detailed log of my observations of Buzzard movements over the Benacre National Nature Reserve and its environs each spring from 1989 to 2006, except in 2001, when foot and mouth disease restrictions prevented site visits. Since 2006, the presence of breeding Buzzards nearby has complicated the picture, though certainly fewer than usual passage birds were observed in north Suffolk in 2006 and 2007. The Benacre records up to 2005 form the basis of this account, which aims to assess the numbers and seasonal pattern and suggest the likely origins and destinations of passing Buzzards observed in Benacre district. These results are then compared with movements reported elsewhere in coastal Suffolk and in neighbouring coastal counties, using information in county bird reports. Methods: data sources and analyses Detailed study at Benacre: Systematic 'sky-watches' were made from a vantage point lkm inland between Benacre and Covehithe. From 1996 to 2005, I made a total of 146 timed watches (280 hours) on mornings, when weather seemed favourable, between extreme dates of February 19th and May 5th. Of these, 64 were in the second half of March and 30 in the first half of April.

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Suffolk Birci Report

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During these four weeks Buzzards were seen on 80% of watches during the first ten days, decreasing in frequency to 30% in the last 10-day period. The site provided good views of an arc between north-west and east, that is across the Benacre NNR woodlands and over coastal fields between the broad and Covehithe cliffs. There were partial views inland, to west and south-west, but none to the south due to adjacent woods. Each spring a series of morning watches was made in 'fair' weather throughout March and late Aprii; avoiding misty, dull, wet or windy days when raptors were unlikely to be moving. For each watch the following détails were recorded: start and finish times, weather and visibility conditions (sunshine/cloud amount, haze, wind direction and strength), timing of each sighting and number of birds, flight directions, estimated flying height, other behaviour, and any distinctive plumage features. Supplementary records from other observers for periods not covered by me are also included. Regional study: For comparison with Benacre observations, both published and reliable unpublished spring records have been collated from ail north Suffolk coastal districts, south to the Aide Estuary and north to the county boundary around Fritton and Ashby. The spring abundance is then compared with sightings in ail months to show the seasonal pattern of Buzzard presence. Similar analyses were then made for the entire coast of Suffolk and likewise for Norfolk and Essex (county bird reports) and for Kent (from Kent Ornithological Society database). Analysis of records: When analysing the records, including those at Benacre itself, considerable problems were caused by the conspicuous mobility of the Buzzards, not only on a day-to-day basis but also at an hourly time scale. Most observations related to birds flying overhead north or south in the coastal zone, mainly east of the A12 main road. A preliminary examination of records, particularly those for groups of Buzzards, indicated significant duplication could occur between sites on the same day and over consecutive days, with apparently the same birds heading in contrary directions; say, northwards one day and south the next. Group size could also change, as birds joined or split off from a group. At the other extreme, it was evident, from circa-daily observations, that individuai Buzzards and small groups could remain within a limited area for up to a week and then be reported by différent observers. Accurate évaluation of numbers is thus not realistic. Instead, 'best estimâtes' are given for the numbers present in successive 10-day periods after eliminating obvious cases of duplication. Even so, these values should be regarded stili as somewhat over-estimating the true numbers; for example, individual Buzzards could be present at a site from one 10-day period into the next. Occasionally, birds with distinctive plumages or a missing flight feather were used as 'markers' to confirm such cases or to track locai movements. Finally, the diagrams that follow will compare the best estimâtes with the total numbers of birds reported, using the aggregated sightings in each period. Results 1. Buzzards at Benacre (a) Numbers The numbers of Buzzards recorded each spring from 1989 to 2005 are shown in Figure 1. In the first six years birds apparently were very scarce, with fewer than 5 birds noted in a year, though an element of under-recording seems likely. A sudden increase in 1995 heralded the recent era of far more frequent sightings, doubtless aided in part by increasing observer awareness and watching effort. There is a wide contrast between the published

28


Spring Movements

of Common Buzzards along the Suffolk

Coast

totals of birds reported and the best estimâtes after making allowance for duplicated sightings. Over the last 11 years numbers have fluctuated considerably between best estimâtes of 30-40 birds in 'good' springs (1995, 1999, 2000) and only 5-10 in 'poor' springs (2001, 2004, 2005 and 2006 (not shown)). Figure 1. Buzzards at Benacre: spring totals, 1989-2005

s birds reported

• estimateci total birds

m ira "O o 2

EO

I

S Sì

I,

The overall seasonal pattern of occurrence during the first half of the year (Figure 2) shows an occasionai presence of one or two Buzzards during winter preceding a prominent spring period of abundance in March and April, after which only very occasionai stragglers or Wanderers were noted into early June. The main spring passage typically was during March 10th-30th, but it was later in 1995 when an exceptional 30 birds flew in from out to sea near Beach Farm on April 4th. In three other years there were small movements of 5-8 Figure 2. Buzzards at Benacre: spring passage pattern, 1989-2005 ' aggregated total no. of birds reported • estimated no, presenti

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11

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29


Suffolk Birci Report

2006

birds as late as mid to late April (16th-25th). The timing of the main movement at Benacre varied between years. Thus, peak periods with day-counts of ten or more Buzzards occurred as follows: 1995 (30 - April lst-5th), 1996 (13 - March 26th-31st), 1997 (ten March 16th-20th), 1999 (17 - March llth-15th, 2000 (12 - March 21st-25th), 2003 ( 1 4 - M a r c h 16th-20th, 11 - 21 st-25th) and 2004 (ten - March 21 st-25th). (b) Behaviour The birds observed during morning sky-watches had either roosted the preceding night in Benacre woodlands or were arriving and passing over from more distant coastal and inland sources. During March and April, the aerial activity of both groups, and hence the chances of seeing Buzzards, was heavily influenced by ambient weather conditions. The best conditions were a bright or sunny morning with very light to moderate breezes (Beaufort force 1-4) from inland that allowed cumulus clouds and thermals to develop, or at least provided some lift. Onshore easterly winds suppressed activity even on sunny mornings that were also often hazy. Roosting Buzzards would begin to lift in ones and twos from various points in nearby woods at around three hours after sunrise. Their behaviour then could vary rapidly from (a) circling and drifting to and fro low over the area, then dropping back into the trees temporarily, to (b) soaring high for short periods before returning to lower levels, or to (c) gaining considĂŠrable height before gliding away well inland or along the coast in either direction. Two such birds were watched thermalling until they disappeared into a cumulus base at ca. 1000 metres (3000ft)! Individuals and groups often joined other birds from nearby roosts or became mixed with newcomers arriving from further afield. The movements changed constantly, so that keeping track of 2-3 groups simultaneously could pose problems. Some arrivais seen approaching from north-west on one occasion included an escaped Red-tailed Hawk B. jamaicensĂŹs, that had been seen at Ashby woods the previous day. On that date, a group of Buzzards had been seen departing Ashby in a south-easterly direction (i.e. towards Benacre). On the 'busiest' mornings up to 10-15 Buzzards could be visible at one time. Irrespective of activity levels, however, almost ali birds had disappeared by mid-day and only an occasionai bird was seen during early afternoon watches. Birds that had roosted in Benacre woods presumably had arrived (unseen) later on the preceding day. I noted the flight directions of 200 Buzzards as they dispersed from the Benacre woods vicinity. The majority (46%) headed south or south-easterly down the coast, while 25% flew north or north-west up the coast and 10% went inland to west or south-west. The remaining 19% departed out over the sea, on east or north-easterly headings. (c) Seaward departures in spring I observed Buzzards (total 35) flying out to sea from Benacre on four occasions and all in the second half of March. Behavioural dĂŠtails and ambient weather (below) showed that Buzzards departed the coast 3-5 hours after sunrise, in light offshore (tail) winds and with sunny clear conditions. (i) 1996, on March 28th, light W breeze with sunny periods and clear visibility between 09.50-10.15 hrs, a total of 13 birds rose from the woods in five groups (2, 2, 3, 5, 1), gathered and soared swiftly, then flew eastwards out to sea until lost to view in the x32 telescope. (ii) 1998, on March 20th, sunny and clear with a light NW breeze - two Buzzards arrived from the north-west then headed purposefully ESE out to sea at ca. 100 metres (300ft), at 09.10 hrs.

30


Spring Movements

of Common Buzzards along the Suffolk

Coast

(iii)

1999, on March 14th, fine and sunny with a light to moderate W wind (with R.Walden) - 17 birds that appeared to have arrived in two flocks from the north or north-west were in view at 11.05 hrs. Of these, six flew off south down the coast as the other 11 formed a rising 'stack' above the Broad before flapping and gliding away high out to sea in a NE direction, being last visible as tiny specks in the telescope at 11.20 hrs. (iv) 2003, on March 23rd, calm, warm, very sunny and clear - a group of nine Buzzards, that had assembled over the woods from several directions since 09.45 hrs, began to soar in a tight spiral or 'stack' at 10.28 hrs; reaching ca.130 metres (400ft) height, they then suddenly headed off in line astern fast to cross the coast near the Broad, using continuous powered flight. They were last seen climbing steadily over the sea and heading purposefully east until beyond telescope range at 10.58 hrs.

(d) Arrivals from offshore in spring An unprecedented event occurred at Benacre on 4th April 1995, when a series of groups totalling 30 Buzzards came in off the sea near Beach Farm and then continued heading to the north-west (C.A.Buttle, pers.comm., Piotrowski 2003). This movement started at 09.30 hrs with a group of nine, followed by other groups of up to five through to the afternoon. It was thought that the birds probably had been coasting northwards after, perhaps, a (ca. 100km) northerly crossing of the outer Thames Estuary from Kent. However, synoptic weather charts, and my own observations during a seawatch at Covehithe that morning, reveal that these Buzzards would have encountered a weak cold front with thick overcast conditions (not conducive to lift) that reached this area at 08.30 hrs after a fine start. The front then moved south quickly during the observation period. It cleared at around 10.30 hrs to give bright sunshine and fine visibility, as the earlier very light W S W breeze veered to a light N N E breeze. Given the distance from Kent and early 'arrival' times of the first groups - especially as compared with later (mid morning) departure times seen at Benacre - plus the deterioration in weather that morning, together suggest a more likely and closer origin for this movement. A series of Buzzard groups probably had departed from various points further down the Suffolk coast ahead of the cold front and had then aborted when at different distances offshore, as lift diminished and a head wind developed. Buzzards have also been observed coming 'in/off' the sea in spring at other locations in north Suffolk (SBRs). On 14th March 1999, five came in at Gorleston and a total of 15 flew west inland over Oulton Broad during that morning. These included a party of 12 circling extremely high, in and out of a cumulus cloud base, before heading west inland at noon (R.Smith, pers.comm.). This sighting was made only 40 minutes after 11 birds had flown out to sea at Benacre (see above). The timings suggest that the Benacre birds might have aborted their departure. On 8th April 2001 at Lowestoft, five came in then headed west with a moderate W N W wind and clear sunny conditions (SBRs). At Minsmere, a flock of 12 arrived from NE at 09.50 hrs on 22nd March 2004 in sunny, clear weather and a light/moderate west wind. This timing was far too early in the day for a true migratory arrival, but instead presumably indicates birds returning to the coast after aborting an emigration attempt. (e) Other features Although resident Buzzards are most vocal raptors in spring, the Benacre birds were rarely heard to call even when soaring together, not even when occasionally jousting 'playfully'. This behaviour is typical of migrating Buzzards in spring through the Middle East (pers.

31


Suffolk Birci Report

2006

obs.). However, two birds indulged in some low intensity 'display' on 17th April 2000 (A.Watson, pers.com.). Elsewhere, two were seen 'displaying' at Ashby Warren on 14th March 1998 (SBR). No Benacre birds were seen to attempt hunting. Another interesting feature of Benacre birds was the predominantly dark brown breast and belly plumage of many individuals, with an absence of the pale pectoral 'horseshoe' band characteristic of adults in the British population. Several birds also showed prominent pale creamy ventral areas, a variant that also is uncommon among native Buzzards. 2. Seasonal occurrence throughout coastal Suffolk Nearly all (> 95%) of the coastal Buzzards recorded were seen north of the Aide Estuary. The monthly pattern of sightings through the year in this sector is shown for the period 1989-2005 in Figure 3; Benacre data are incorporated. The main features to note are the contrast between high numbers reported during spring and low numbers during the autumn passage period of raptors. Since 1995, the strength of the spring movement has varied widely between years, as at Benacre; from best estimâtes of ca. 70 birds in the good springs (1995, 1999, 2003) to ca.30 in the 'poorest' (1996-7, 2001 and 2005). It should be noted that in 2001 observations were curtailed by foot and mouth disease access restrictions. As noted later, variations in the strength of the spring passage of Buzzards observed in Suffolk were strongly correlated with numbers in both Norfolk and eastern Kent (Figures 4 and 6) but not with immigrant numbers in the preceding autumn. Figure 3. Buzzard passage in north coastal Suffolk: spring and autumn, 1989-2005 350

T~

| n birds reported

â&#x20AC;˘ birds estimateti |

o o

Many spring records refer to the Benacre area. Away from there, only four groups of I0-15 Buzzards were reported - llying over Minsmere, Oulton Broad and around the Fritton-Ashby woods, as noted above. Interestingly, as long ago as 1973 a spring flock of ten Buzzards had been recorded drifting over Minsmere on the very late date of 29th April (Piotrowski 2003). That was long before Buzzards began spreading back from western counties. The distribution of spring numbers is symmetrical about the peak four weeks in March and April, whereas autumn records were more scattered yet showed a small peak in mid-September. Figure 3 also indicates a paucity of wintering birds and Buzzards were rare

32


Spring Movements

of Common Buzzards along the Suffolk

Coast

during July and early August. In 1996 and more recently, however, birds have summered at Ashby woods. To the south of the Aide Estuary, only occasionai ones and twos were reported at any season, even at the migration watch-point at Landguard Point observatory. The scarcity of Buzzards in south coastal Suffolk during these years was typical also of coastal Essex in those years (see below). 3. Buzzard movements around adjacent coasts The Suffolk observations can also be assessed in the context of recorded Buzzard movements elsewhere around the coasts of East Anglia and the Thames Estuary, using published information in Norfolk, Essex and Kent bird reports. (a) Norfolk The numerous records of Buzzards seen within about 10 km of the coast were assessed for the 13 years 1989-2001, since when the risk of confusing visiting Buzzards with the expanding resident population has become too high. The picture from Norfolk resembles closely that from Suffolk, with a sudden increase in passage from <10 birds per year to perhaps ca.65 birds in spring 1995; after which numbers varied between 65 again (in 1999) and 20 (in 2001 ). The numbers in 1995 were 'unprecedented' (Taylor et al., 1999). The two largest spring movements (1995 and 1999) corresponded with the two best years in Suffolk. Indeed, spring totals in these two adjoining counties were strongly correlated during 1994-2000 when sufficient data were available for Norfolk (Figure 4). The seasonal pattern of Buzzard occurrence in coastal Norfolk (Figure 5), also matched closely that in Suffolk (Figure3), except that the spring peak was later (April lst-20th) than in Suffolk (March 10th-31st). Reported spring flight directions differed markedly around the long convex coastline. Most (67.5%) Buzzards flew south or south-west down the east facing sector but west (79.5%) along the north coast. Westerly movements included 13 on March 3Ist 1996, 18 on the late date of May 8th 1999, while a remarkable 32 past Sheringham on April 20th 1995 included a flock of 21 Buzzards. Could these have included some of the 30 birds seen at Benacre 16 days previously? Clearly, unusually large numbers were moving around the East Anglia coast in that Aprii - perhaps 'in excess of 50' in Norfolk (NBR). (b) Essex In spring, Buzzards were scarce visitors to the extensive open coastal farmlands and estuarine habitats east of the A12. Only 12 singles were recorded in March or Aprii over the 15 years 1987-2001 (Essex Bird Reports). Further inland, in the more wooded country, breeding was first proved in 1994 and at least 28 pairs were nesting by 2005. (c) Kent (east) Passage Buzzards were noted each spring (1990-2005) on the east-facing coast, from the Thanet promontory ('tip of Kent') southwards to Folkestone; but were scarce along the north coast. Estimated spring numbers increased steadily from <10 per year in 1990-94 to 50-60 in 1999, after which annual numbers varied between 30-60 birds. Note that 1999 was also a peak Buzzard spring in Suffolk and Norfolk. The six highest county day-counts of 10-22 birds, ali but one between March 12th-27th, were from Thanet. Spring totals in Kent were positively correlated with numbers in coastal Suffolk (Figure 6) and, by inference (Figure 4), also with those in coastal Norfolk. Also, as in Suffolk, spring and preceding autumn numbers of Buzzards were not correlateci, although there was a slight tendency for larger spring numbers following an autumn influx. The passage period broadly resembled that in East Anglia, but started with an abrupt mid March peak, followed in some years by

33


Suffolk Birci Report

2006

a secondary peak in late April and early May. Most Buzzards coasted either north or south along this Channel sector; very few went inland. Around Thanet, coasting movements were complex, but apparently none followed the north coast westwards towards the Thames and Essex. Buzzard immigration from France was observed at cliffs fronting the narrowest (32 km) crossing. A total of ca.30 birds (13 sightings) has been observed 'flying in off the sea' in eight springs between February 22nd and May 29th, but mostly during March 13th-28th and including groups of 5-6 birds on four occasions. All arrived between 09.15-14.30 hrs. At Foreness/North Foreland (Thanet) 1-3 Buzzards have been watched on four occasions departing high out to sea until lost to view in fair weather with light breezes (S.Mount, in litt.). Departure headings varied between NW towards Suffolk (twice) and ENE with departure times between 07.40h and 13.1 Oh. Figure 4. Buzzards: Spring totals, Suffolk and Norfolk, 1994-2001

4. Discussion This paper has documented the large increase since 1995 in the numbers of Buzzards recorded passing in spring through coastal Suffolk and which may involve not less than 50 birds in some years. Similar changes have happened also in coastal Norfolk and eastern Kent, though not in coastal Essex. Indeed, except in Essex, the annual variations in spring Buzzard numbers are closely correlated between counties (Figures 4 and 6). These spring movements in Suffolk and Norfolk are acknowledged to be a true change in status (Piotrowski 2003, Taylor et al., 1999) and not simply a product of increased observer activity. Autumn Buzzard numbers, on the other hand, were relatively low, except in Essex and Kent, while wintering birds have remained rather scarce throughout this zone in all four counties. The origins of, and routes taken by, the spring Buzzards passing through our region are not known, given a lack of any direct evidence from ringing, but clearly they must be drawn from either the resident British or migratory north European (mainly Scandinavian) breeding populations. (a) Potential Sources of Spring Buzzards British population The upsurge in spring sightings since 1995, which has coincided more or less with the

34


Spring Movements

of Common Buzzards

along the Suffolk

Coast

initial recolonisation of Norfolk, Essex and western Kent by breeding Buzzards since the mid 1990s, suggests a possible link between the two events. Could Suffolk coastal birds be part of the recolonisation process, representing either wandering Norfolk offspring or prospecting immatures spreading here from further west? This proposal is not supported, however, by the fact that young Buzzards (a) seldom disperse further than 30 km from their natal sites before settling to breed (Wernham et al., 2002) and (b) are not known to collect into mobile flocks, except in autumn in Devon - where densities of the very territorial adults are high (Dare 1999). On the other hand, in coastal Norfolk nowadays, and probably also in Suffolk, an increasing proportion of autumn sightings could be of locally bred juveniles dispersing. Continental populations Buzzards at Benacre, and elsewhere along the Suffolk coast, showed typical migratory behaviour - restless localised movements by silent groups and single birds, with roosting overnight in groups of ten or more in woodlands at the coast - that culminated in some flocks flying determinedly out to sea until beyond sight in fine weather. Here, too, and elsewhere around Lowestoft, groups seen flying ashore in the morning were indicative of aborted departures. The whole impression thus was of migrant Continental Buzzards gathering at Benacre to await favourable conditions, before attempting the almost 200 km crossing to the nearest Dutch coast. However, Common Buzzards, unlike Honey Buzzards and Rough-legged Buzzards, are not strong fliers over the open sea. A crossing to Holland, even in fine weather, would take probably 5-7 hours and require (as observed) the Buzzards to depart as soon as sufficient thermal lift developed (a few hours after sunrise) and with a tail-wind. Birds of the highly migratory Steppe Buzzard race B.b.vulpinus, when over-flying arid terrain in Israel, have achieved average cross-country speeds of 35 km/h by flap-gliding at altitude; a performance that is enhanced by tail-winds (Spaar 1995). Indeed, some raptors, especially falcons, seek a following wind, or even a side-wind, for a sea crossing and do not depart into head winds (Meyer et al., 2000). The timing of the spring peak in Suffolk, in mid/late March, is consistent with that of adult Scandinavian Buzzards returning north from wintering areas in France, Belgium and adjacent countries (Cramp and Simmons 1980) or, for a few, sometimes in eastern England. Their spring movement reaches Denmark in early March, southern Norway in late March and central Norway by early April. By that time, breeding Buzzards in Britain will have completed nests and be preparing to lay clutches. Consequently, the occasional late April and early May movements through our region, notably in north Norfolk in 1995 and 1999, would seem likely to involve mostly the later-returning immatures. Pathways of arrival Perhaps the most intriguing problem is determining where the Buzzards seen at our coast in spring have arrived from and by what routes. Did they cross the North Sea to the east coast during the preceding autumn to over-winter in East Anglia or nearby counties and then filter back to this nearest point of departure for the Continent; or did they cross the Channel into Kent in spring then make their way northwards? Perhaps, in some years a combination of both processes has occurred. Another problem is posed by the Buzzards observed around the Norfolk coast, particularly the dichotomy in their prevailing flight directions along the northerly and easterly facing sectors. Autumn immigration: Occasional 'in/off' sightings of Buzzards along the coastline from Norfolk to north-east Kent, confirm, in the absence of ringing recoveries, that small-scale

35


Suffolk Bird Report

2006

Figure 5. Buzzards in coastal Norfolk, 1993-2001 0

no. birds reporteci • estimateci no. birds

„„.Fili fili i l

I I i ri [ b r i n a l i

Ì 11 ì l i b i c a ™

immigration of Continental birds does occur in some years from mid September through October. This timing matches tliat of the main exodus from Scandinavia as recorded over Falsterbo, at the southern tip of Sweden. Furthermore, some Buzzards reach our coast during periods when Rough-legged Buzzards are arriving. However, total immigrant numbers in East Anglia appear to be small (Figures 3 and 5) and are not correlated with Buzzard numbers in the following spring. Spring passage migrants: The fact that spring Buzzard numbers in Suffolk are positively correlated with numbers in east Kent (Figure 6) suggests that migrants can reach Suffolk from east Kent, where immigration from France is observed across the Dover Strait during weeks when increased numbers appear on our coast. However, an onwards route for these Kent birds is not yet demonstrated conclusively. Scandinavian birds in Kent would be well Figure 6. Buzzards: Spring totals, Suffolk and Kent, 1991-2005

East Kent coast

36


Spring Movements

of Common Buzzards along the Suffolk

Coast

off-course and therefore might be expected to re-cross the Strait rather than continue northwards into East Anglia, before trying a much longer return over the Southern Bight. Indeed, there is positive evidence from Kent that some birds do head (back) to France, via the shortest crossing. In addition, a few Buzzards on Thanet have been observed departing out over the sea N W towards East Anglia or ENE for the Continent. Such departures, coupled with other Thanet birds seen returning south, presumably to re-cross the Channel, would explain the paucity of spring sightings along the Thames coasts of Kent and Essex and in south Suffolk. A Buzzard leaving Thanet northwards at 600 metres (2000 feet) altitude on a clear day should be able to see the Suffolk coast line 50-80 km ahead, as well as the entire Stretch of the north Kent and Essex coasts. By comparison, the nearest Continental landfall to eastward would be some 110 km away in Belgium. Clearly, more detailed observations of Buzzard movements, including ambient weather data, are needed from Kent and Suffolk to resolve these questions. In particular, do any Buzzards complete a direct sea crossing of the outer Thames Estuary from north Kent to reach Suffolk? In Devon, personal observations (Dare 1999) show that some spring passage Buzzards glide over at high altitudes and are only detected by chance when watching other raptors circling lower down. How many high-fliers are being missed in Suffolk and neighbouring counties could best be ascertained from dedicated 'sky-watching' in spring from strategically located vantage points. The best conditions would be on sunny and clear days with fair weather cumulus or high cirrus clouds, as these conditions both stimulate high Aying by Buzzards and provide ideal skyscapes for Spotting migrating raptors. There is stili much of interest to be learned about visible overland migration of raptors. 6. Conclusions The increased numbers of Buzzards observed in spring (March-April) in coastal Suffolk over the past decade are part of a wider and (as yet) unexplained phenomenon extending to coastal Norfolk and eastern Kent, though not to Essex. Many Buzzards exhibit migratory behaviour and groups have been seen Aying eastwards out to sea at Benacre, the nearest favourable departure point to the Continent. Spring groups probably comprise mainly Scandinavian passage migrants, which are off-course after crossing the Dover Strait, together with some departing winter visitors. The route(s) by which Buzzards may reach Suffolk after arriving in Kent are stili to be discovered. Any wandering immature Buzzards from the expanding breeding population in East Anglia are thought not to be mvolved in these prominent spring movements. Acknowledgements The other regular Benacre 'sky-watchers' were Chris Darby, David Riley, Ally Riseborough, Dick Waiden, and Alee and Kay Watson; to ali, my thanks for their records and camaraderie. Several other observers kindly provided occasionai Buzzard sightings from Benacre and the surrounding district - Carl Buttle, Colin Carter, Derek Eaton, Andrew Easton and Paul Read. Finally, I am especially grateful to Tim Hodge (Kent Ornithological Society recorder) for kindly supplying database records, Simon Mount for his detailed observations from Thanet and to Rob Clements, Francis Solly and David Davenport for guidance with interpreting the Kent records. References Clements, R. (2000). Range Expansion of the Common Buzzard in Britain. British 93: 242-248.

37

Birds,


Suffolk Bird Report

2006

Cramp, S.C. and Simmons, K.E.L. 1980. The Birds of the Western Palearctic. Vol. 2. Oxford University Press. Dare, P.J. 1999. Large Movements and Ground Assemblies of Buzzards in Devon. Devon Birds, 52: 3-9. Meyer, S.K., Spaar, R. and Brudener, B. 2000. To cross the sea or to follow the coast? Flight directions and behaviour of migrating raptors approaching the Mediterranean Sea in autumn. Behaviour, 37: 379-399. Piotrowski, S. 2003. The Birds of Suffolk. Christopher Helm, London. Spaar, R. 1995. Flight behaviour of Steppe Buzzards (Buteo buteo vulpinus) during spring migration in southern Israel: a tracking study. Israel Journal ofZoology, 41: 489-500. Taylor, M., Seago, M â&#x20AC;&#x17E; Allard, P. and Dorling, R. 1999. The Birds of Norfolk. Pica Press, Sussex. Wernham, C., Toms, M., Marchant, J., Clark, J., Siriwardena, G. & Baillie, S. 2002. The Migration Atlas: Movements of the Birds of Britain and Ireland. T. & A.D. Poyser, London. Dr P.J. Dare, 2 Corn Hill, Back Road, Wenhaston, Haiesworth,

Blackbird Donald

/

38

Simpson

Suffolk IP19 9BW


Suffolk Birci Report

2006

Recent Amendments to the Suffolk List Philip Murphy, Brian Small, Malcolm Wright and Justin

Zantboer

The review of records of Upland Sandpiper and Pechora Pipit in Suffolk Brian Small - on behalf of the BBRC and SORC Anyone reading thoroughly the British Birds Rarities Committee's Report on Rare Birds in Great Britain in 2005 - part 2: passerines (British Birds, Vol. 100, February 2007 p.72-104), and with an interest in Suffolk birds, may have found, tucked away at the end under Appendix 1 (the list of records not accepted), the décision to delete two previously accepted records. The Upland Sandpiper Bartramia longicauda, at Minsmere on 24th September 1964 and the Pechora Pipit Anthus gustavi, at the same site on 27th Aprii 1975, were the sole Suffolk records of these two rarities and the only accepted records for East Anglia. I have been asked to explain the reasoning behind the recent décision, from my position on both the BBRC and the Suffolk Ornithological Records Committee (SORC). The review of the two records by the BBRC had been prompted by a request from the SORC, following a review of the Suffolk list, coupled with questions raised by one or two of the locai birders around at the time of the records. The BBRC does not enter lightly into the re-evaluation of early records. Indeed we face a number of challenges, both in searching out the material for re-assessment and in getting contemporary views of birders (in these cases from 1964 and 1975). The value of the BBRC archives is that such material does not get lost and we were able to get the opinions of several of the locai birdwatchers from the 1960s and 1970s. In addition, we face the problem as to whether we should apply modem criteria to early records - and I shall go into this in more detail later. Upland Sandpiper at Minsmere, 24th September 1964 Prior to the Suffolk record, there had been just 15 records for the UK and ali but three had been shot (these three had been in Pembrokeshire in October 1960 and 1961 and Scilly in November 1960). To date there are stili only nine records away from the southwest or extreme north of the UK. According to The Birds of Suffolk (Piotrowski 2003), this bird was seen briefly by four observers in flight over the reserve and nearby fields, though in fact it was also seen on the 'ground' - perched on a fence post, calling. As most views were in flight, the détails provided were necessarily, and relatively, brief and the identification as Upland Sandpiper was largely based on the shape of the bird (with one or two drawings showing it in flight from below), aided by some plumage détails noted whilst briefly, and a little distantly, perched. Those that have seen Upland Sandpiper will have been Struck by the distinct shape of the bird in flight and perched. In flight the long, slim tail may be apparent, as might the barred underwings, and it often calls; on the ground it has a very slim-necked appearance, with a distinct head pattern and plumage features. Though alluded to, the description failed to really capture the 'feel' of the species and, given the views, the criticai plumage détails were fairly vague. Though the bird might possibly have been an Upland Sandpiper, it was feit by the BBRC that elements contained in the descriptions were not compatible with the identification of it as such and the record was therefore deemed unacceptable. Pechora Pipit at Minsmere, 27th April 1975 Pechora Pipit would be a major claim away from Shetland even today, so, with just 12 prior

39


Suffolk Birci Report

2006

records accepted up to April 1975, this would have been the first in spring and it stands out in many other ways - there are still only seven records away from the 'strongholds' of Shetland and Fair Isle. I believe there had been mutterings in the past about the validity of the record, so when a semi-formal submission raised further questions, a request for a review was made to the BBRC. The views of this bird were very much better than those of the Upland Sandpiper, allowing for criticai assessment by the observers of many plumage détails, even features such as the pattern of streaking on the rump and uppertail coverts. Unfortunately, given these close views, a number of the structural and plumage features described were not strongly indicative of Pechora Pipit: for example though it was seen to have pale mantle stripes, on Pechora Pipit these are often much stronger than described, white (or almost white) and contrast strongly with black feather centres. Also, critically, although they saw streaking on the rump, at no stage did they note that the tertials feil short of the primary tips - a feature diagnostic of Pechora Pipit. Düring assessment, the pitfall of a 'non-breeding plumaged', Red-throated Pipit was raised a number of times, as they possess many or all of the characters described for the pipit at Minsmere. In addition, several other features of Pechora Pipit (e.g., its strong bill and the yellowish wash across the breast) were not noted. Pechora Pipit also has a distinct character - often rather secretive - plus a diagnostic call (when heard, like a Grey Wagtail), and none of these elements was noted in enough detail (or at all) and so did not rule out the fact that a mistake may have been made. Some have asked, given that crucial elements which differentiate Red-throated and Pechora Pipits were missing, how this record was accepted in the first place? This, of course, raises the issue of applying modern identification criteria to old records. Ian Wallace in Beguiled by Birds (Wallace 2004), sees this as an 'ever more zealous approach to record review'. The BBRC takes such things into account during a review of old records and does not simply 'chuck things out' if they do not match up to modem expectations. In fact the opposite is often true; many old records contain such carefìil observations and notes that subtleties of plumage and behaviour of the species claimed are found in the descriptions. However, in truth it is likely that in this case a simple mistake may have been made, given that at the time the difficulties of identifying Pechora Pipit were not fully understood. Surely, a relatively important record must stand the test of time; the fact that several criticai features that would have confirmed the pipit's identity were not noted, even though it was seen at close range, deems it unacceptable. Rogers, M., et al., 2007. Report on Rare Birds in Great Britain in 2005. British Birds. 100, February 2007, 72-104. Piotrowski, S., 2003. The Birds ofSuffolk. Christopher Helm, London. Wallace, I., 2004. Beguiled by Birds. A & C Black Ltd, London. Other Recent Amendments The following is intended to clarify the status of several other species that have occurred in Suffolk. Snow Goose Anser eaerulescens There is a problem with many wildfowl records in that birds frequently escape from collections and it is often impossible to determine the true provenance of an individuai seen in the wild. Snow Geese are quite often reported from différent parts of the county (see Appendix lì - Category E species) but it is clear that almost ali of these are escapees.

40


Recent Amendments

to the Suffolk

List

Snow Geese ringed in North America have been recovered in Europe, so wild birds can certainly occur, but there is no proof that any of the Suffolk records to date refer to genuinely wild birds. In these circumstances it is better that at present this species is not considered to be part of the Suffolk list. Pacific Golden Piover Pluvialis fulva This species has been included on the Suffolk list in the past on the strength of a record of one seen briefly on Breydon Water on May 28th 1992. It was initially seen amongst a flock of Grey Plovers but disappeared after the flock was disturbed by a Peregrine Falcon. However, there appears to be no conclusive proof that this bird was seen south of the Breydon Water Channel, the geographical county boundary with Norfolk, so it is best regarded as not forming part of the county list. Pacific Golden Piover is now conclusively on the Suffolk list on the strength of a more recent occurrence. One was found by Will Brame at Levington Creek, on the River Orwell on August 26th 2005 and was seen by many observers during its six-day stay. A full account is given in Suffolk Birds 2005, p i 6 9 . Eskimo Curlew Numenius borealis The BOURC have recently reviewed old British records of Eskimo Curlew. This North American wader (probably now extinct) is on the Suffolk list on the strength of two said to have been shot near Woodbridge in November 1852. One of these was preserved and was later examined by Gurney, who verified the record. The other bird was not preserved and is no longer, therefore, considered acceptable. A single record, therefore, remains on the Suffolk list. Pacific Swift A pus pacifĂŹcus The first record for the Western Palearctic concerned a bird that was found alive on the Leman Bank gas platform, 45 km ENE of Happisburgh, Norfolk, on June 19th 1981. It was then transported by helicopter to Ellough Airfield, in Suffolk, where it was identified and then released and it was watched feeding nearby until dusk. It was seen very briefly the next morning by one observer at nearby Shadingfield. In order to clear up confusion surrounding the status of this bird, Philip Murphy wrote to Tim Meiling, then secretary of the British Ornithologists' Union Records Committee BOURC), early in 2007. We quote from Tim Meilings' reply: "I'm not surprised that you are confused as this is probably the most complicated record I have come across. Pacific Swift was added to Category A of the British List on the basis of the 19th June 1981 Leman Bank gas platform individual. It was announced as such in the 1 Ith BOURC annual report in Ibis (Vol.126 p.441) in December 1983. It was temporarily transferred into a "new" Category E in the 13th Report (Ibis, Vol. 130 p.335) in December 1987, because it had occurred beyond the 3 mile limit. But we then got rid of this 3 mile rule and readmitted it to Category A (Ibis Vol. 134 p.212) in December 1991. The current categories that BOURC use are all in a paper in British Birds 1998, Vol.91 : 2-11. We now include all records within 200 nautical miles of the British coast, or the halfway point between other countries, whichever is closest. 45 km ENE of Happisburgh puts this record squarely within British territorial waters. However, Category E includes "human assisted transportees" which might preclude it from appearing on the Suffolk List, as it was transported and released in Suffolk. BOURC admitted this species to the British List because it had arrived without deliberate human Intervention on the Leman Bank gas platform (i.e. in British waters). However, if it had

41


Suffolk Birci Report

2006

arrived at a gas platform say 45 km off Norway and was then transported to Britain (i.e. in captivity), we would not have admitted it". It was clear to SORC on deliberation that, for Suffolk, this species comes under Category E and should not form part of the full Suffolk list, because its arrival into the county was "human assisted". At the time this species enjoyed the possibly unique status of being on the British List but not on any county list, but there have since been a further three accepted records of Pacific Swift in mainland Britain. American Robin Turdus migratorius A first-winter male was found freshly dead on top of a container being loaded onto a ship at the Felixstowe Dock Basin on November 1st 1994. The container had previously been stored at the Trinity Terminal. Unfortunately it is unclear how the corpse came to be on top of the container and there is no proof that the bird had reached Suffolk alive and so it is best regarded as not forming part of the Suffolk list. The specimen is now stored at the Ipswich Museum. The occurrence was reported in the 1994 Suffolk Bird Report (Vol.44) but within square brackets. Sub-species The following three records of sub-species of the Yellow Wagtail Motacilla flava were never submitted to the British Birds Records Committee (BBRC) and are therefore unverified and do not form part of the Suffolk bird list. Ashy-headed Wagtail Motacilla flava Butley: male, 7th May 1977 Alton Water: male, 22nd May 1977 Eastern Blue-headed Wagtail

Motacilla

cinereocapilla

flava

simillima

Minsmere: 16th November to 8th December 1967

There are two further species, Lesser White-fronted Goose and Sharp-tailed Sandpiper, which SORC voted to remove from the Suffolk list in 2004. Further research is being undertaken on these records and they will be dealt with in a future edition of Suffolk Birds.

42

Suffolk Birds 2006 Part 1  

Volume 56

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