Page 1


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

North-East Area Recorder David Thurlow, 1 Ness House Cottage, Sizewell LEISTON IP16 4UB Tel: 01728 832719 E-mail:

South-East Area Recorder Lee Woods, 5 Gretna Gardens IPSWICH IP4 3NT Tel: 01473 727324 E-mail:


SUFFOLK BIRDS VOL. 52 A review of birds in Suffolk in 2002

Editor Malcolm Wright

Assisted by Adam Gretton (Papers) Rob Macklin (Systematic List) Philip Murphy (Systematic List) Trevor Kerridge (Photos) Tony Howe (Artwork) Paul Gowen (Printing)

Published by S U F F O L K N A T U R A L I S T S ' SOCIETY 2003


Published by The Suffolk Naturalists' Society, c/o The Museum, High Street, Ipswich IP1 3QH Š The Suffolk Naturalists' Society 2003 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 0264-5793

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


CONTENTS Page Editorial Malcolm Wright

5

Review of the Year Malcolm Wright

7

Mute Swans in Suffolk 2002 Mick Wright

14

Breeding Waders of Wet Meadows Survey 2002 Mick Wright

19

Snow Buntings Wintering in the Felixstowe Area Nigel Odin

24

Roosting Behaviour of Common Swift Malcolm Wright

26

The 2002 Suffolk Bird Report: Introduction

29

Systematic List

31

Appendices

144

List of Contributors

149

Gazetteer

151

Earliest and Latest Dates of Summer Migrants

153

A Guide to Recording Birds in Suffolk

154

Rare Birds in Suffolk 2002

158

Brian Small

Regional Review Adam Gretton

162

Suffolk Ringing Report 2002 Peter Lack

168

List of Plates Facing

Plate

1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12.

Red-throated Diver Robin Chittenden Great Crested Grebe Alan Tate Black-necked Grebe Derek Moore Little Egret Bill Boston Great Bittern Bill Boston Great Egret Derek Moore Eurasian Spoonbill Derek Moore Bufflehead Bill Boston Great Snipe Andrew Easton Ringed Plover Alan Tate Pectoral Sandpiper Bill Boston Common Snipe Robin Chittenden

Facing

Plate

Page

No.

Page

No.

40 40 40 40 41 41 41 80 80 80 80 80

13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23.

Green Sandpiper Clive Naunton Little Owl Alan Tate Long-eared Owl Robin Chittenden Common Swift Robin Chittenden Alpine Accentor Mike Malpass Black Redstart Robin Chittenden Common Whitethroat Alan Tate Firecrest Alan Tate Wood Nuthatch. Bill Boston Snow Bunting Bill Boston Black-headed Bunting Alan Tate

F r o n t c o v e r : S a n d M a r t i n s Peter

Partington

The copyright remains that of the photographers/artist

3

81 81 81 128 128 128 128 129 129 129 129


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 Dr K. H. Voous's List of Recent Holarctic Bird Species and use of English names should be as in the BOU's 'Checklist of the Birds of Britain and Ireland' (Sixth Edition, 1992). Contributions should if possible, be submitted to the editor on disk and written Microsoft Word. If typed, manuscripts should be double-spaced, with wide margins, one side of the paper only. They must be in the final form for publication: proofs longer papers are returned to authors, but alterations must be confined to corrections printer's errors. The cost of any other alterations may be charged to the author.

in on of of

Photographs and line drawings are required to complement each issue. Suitable photographs of birds, preferably taken in Suffolk, should ideally be in the form of 35mm transparencies. A payment of ÂŁ10 will be made to the photographer for each photograph published and ÂŁ5 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 1 st of each year. Authors of main papers may request up to five free copies of the journal. Suffolk Ornithological Records Committee: Chair: Malcolm Wright Area County Recorders'. Colin Jakes, Dave Thurlow, Lee Woods. Secretary: Justin Zantboer Other Committee Members: Steve Babbs, James Brown, Richard Drew, Stuart Ling, Gary Lowe, Rob Macklin, Steve Piotrowski, Brian Small, Dick Waiden. ADDRESSES Papers, notes, drawings and photographs: The Editor ( S u f f o l k 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 IP I 3QH.


Editorial Within this report the reader will find a paper by Mick Wright giving the results of the Breeding Waders of Wet Meadows Survey 2002. This is a repeat of a previous survey carried out in 1982 and it does not make pretty reading, revealing a further, rapid decline in most of the wader species nesting in this habitat. Northern Lapwing down by 60% over the twenty year period, Common Redshank by 14% and Common Snipe now virtually extinct on these sites in Suffolk, with only six "drumming" birds recorded, a staggering decline of 88%. Under Tree Sparrow, in the systematic list, the reader will find a fieldnote giving dĂŠtails of some counts of that species in the 1981 Bird Report. There was "a flock of ca.1000 at Aldeburgh in January/February, ca.500 at Walberswick in December, while peak passage day at Landguard saw 1100 passing over on October 12th". Contrast that with 2002, when Tree Sparrows were recorded at only 16 sites in the county and at only one of these were double figure counts obtained. Many other examples could be given, especially of farmland birds. We have lost an awful lot in just twenty years and the rate of loss is frightening. The news is by no means ali gloomy. Great Bitterns appear to be responding positively to habitat improvements; we report the first ever nesting of Little Egrets in the county; Marsh Harriers are doing well, while Cetti's and Dartford Warblers are both increasing. The new RSPB reserve at Lakenheath Fen is booming already, from virtually zero to ten pairs of Water Rail, 144 pairs of Sedge Warbler, 355 pairs of Reed Warbler and 87 pairs of Reed Bunting; ali in 5/6 years and on old carrot fields! There are diffĂŠrent strands at work here. Some species (e.g. Little Egret, Dartford Warbler) are increasing their range, probably because of a warming climate. Some other, scarcer species are doing well because of some good conservation work being done by the RSPB, English Nature, the county Wildlife Trusts and other bodies, largely on reserves. It is in the wider countryside and among our commoner birds, that the large scale losses are occurring. The principal culprit is plain to see. Large scale industriai farming, with its drainage of wetlands, removal of so many hedgerows and other habitats and large inputs of fertilisers, herbicides and pesticides, has devastated the British countryside and its wildlife. The * G r e a t Bittern P e , e r B e e s o n damage still appears to be going on, with the various agrienvironment schemes paying out millions of pounds to farmers and landowners, but failing so far to secure any visible improvements. 1t would be unfair to blame every individuai farmer for this state of affairs. Rather the blame should be shared between the policies of successive governments over the past fifty years, the baleful influence of the old Ministry of Agriculture, the agri-chemical industry 5


Suffolk Birci Report 2002 and those farmers who farm solely for short term gain, with no regard for landscape, wildlife, conservation or the future. It should be emphasised that there are those who farm the land sympathetically and practice good conservation and they should be given every fiscal and other encouragement. Such changes highlight the value of your county bird report in documenting population fluctuations on a local scale. So, please keep sending in your records on a regulär basis. It is vital also that everyone interested in our birds supports the local and national conservation bodies, not forgetting the BTO, which does so much valuable scientific survey and research. The RSPB has influence because it has over a million members, more than ali the politicai parties in Britain put together! Certainly we should be in a much worse situation without the work being done by the conservation organisations. A lot of people have contributed to this Report. Firstly I must thank ail those observers who have sent in their records from which the Report is written. The three recorders, Dave Thurlow, Lee Woods and Colin Jakes, have done sterling work entering all the records onto the computer system. My thanks to the species account authors, whose names appear at the beginning of the systematic list, to those who have written extra papers and to the artists and photographers who have made their work available. Two people have helped me especially; Adam Gretton carried out a first edit of ali the extra papers and the systematic list has benefited from a meticulous read-through by Philip Murphy, who corrected many errors and suggested many improvements. Rob Macklin organised the writing of the systematic list and Trevor Kerridge and Tony Howe have respectively gathered together the photographs and artwork. Richard Drew kindly read and commented on the Review of the Year. All the members of the Records Committee have helped in various ways, especially the secretary, Justin Zantboer. The previous editor, Gary Lowe, gave much helpful advice and Paul Gowan has helped to guide the report through the printing process. My thanks also to my family; Rosemary has read all the Report, looking for grammatical and other errors and Alistair and Joanna gave much needed help with IT. Our thanks to Mike Gaydon at Healeys for seeing the Report into print. Malcolm Wright Pakenham

6


Review of the Year Malcolm Wright Another warm and wet year, the fourth in a row. Both winter periods were mild, with no snow to speak of and no prolonged spells of hard frost. The summer was patchy, very warm at times but with no periods of drought and the latter part of the year was very wet. Water levels remained high throughout. During the year 274 species were recorded in Suffolk, which is quite a high total, beating the 272 recorded in 1996. Although no species new to the county were found, there was a decent number of scarce birds and rarities and the accidentals included the first Great Snipe for 30 years, the sixth ever Whiskered Tern, the second Alpine Accentor in the past 100 years and the second ever Black-headed Bunting. It was a remarkable autumn for seabird movement, with an unprecedented passage of Sooty Shearwaters and most other pelagic species in well above average numbers. The highlight of the breeding season was the first ever nesting of Little Egrets in Suffolk. A close second was the building of ten nests by Eurasian Spoonbills at a coastal site. Great Bittern numbers were up slightly and in the Sandlings Dartford Warblers increased yet again, to 61 singing males. January New Year's Day was very cold, with a light snow cover on the ground inland and a penetrating frost. Lackford Lakes was 95% ice covered. By the 5th milder conditions prevailed and it was mainly dry and mild until mid-month. The second half of January was unsettled, with Atlantic depressions bringing regular wind and rain, but it stayed mild throughout. Rainfall and sunshine were close to average. All birders like a decent start to the year and among the good birds seen on the 1st were the long-staying Ferruginous Duck and a Little Auk at Minsmere and an Iceland Gull at Oulton Broad. The flock of Greater White-fronted Geese at Minsmere peaked at 292 on the 5th. The 2001 Ring-billed Gull was refound at Woodbridge on the 5th (after an absence of six months) and a different bird was located at Livermere Lake on 13th. A Slavonian Grebe was off Shotley Marshes on 7th, when five Horned Larks were on Trimley Marshes. Two Long-tailed Ducks arrived at Benacre Broad (for a three month stay) on 12th and the first Wood Lark was heard in song over Hazelwood Marshes the same day. A wandering flock of up to ten Bohemian Waxwings was in the Lowestoft area throughout the month and up to five Hawfinches were to be found on Barnhamcross Common, Thetford. A mobile flock of 4000 Golden Plovers visited the Mickle Mere on 17th, the same day that the Snow Bunting flock on Orfordness peaked at 63. On 22nd, 1752 Guillemots were logged off Kessingland (1115 north, 589 south and 48 on the sea) and on 25th at least 400 Great Crested Grebes were seen offshore from Minsmere. The long-staying Norfolk Rough-legged Buzzard was seen to cross the county boundary at Herringfleet on 29th. February The first half of the month was unsettled, mild, wet and windy. From Nth to 18th an anticyclone brought calmer conditions, but with overnight frosts. Further lows then brought more rain from 19th and by 23rd it was quite wintry with a few snow showers, which quickly turned back to more wind and rain to the month's end. Overall, very mild and very wet. 7


Suffolk Birci Report

2002

No less than five Caspian Gulls were found at Carlton Colville on 2nd and another Slavonian Grebe was at Minsmere on 3rd and lOth. A flock of 1500 Fieldfares was at Holton on 4th, feeding in orchards; the largest congrégation of the winter. Displaced Great Bitterns were found at Ipswich Golf Club on 8th and Lackford Lakes on 1 Ith, while on lOth, 4167 Golden Plovers were counted on the Stour Estuary. Some excellent WeBS counts were made on the Aide/Ore Estuary complex and this included highs of 1053 Avocets and 2477 Black-tailed Godwits. At Oulton Broad on 13th, 55 Tundra (Bewick's) Swans flying east were birds returning early to the Continent. On the same day an excellent count of 15 différent Common Buzzards was made at three locations in south Breckland. The Tree Sparrow flock in a game cover strip at Ampton reached 60 on 23rd, easily the highest count of the year in Suffolk. March Colà and dry weather started the month, with some overnight frost and fog patches. Milder from 5th onwards, then a small intense low on 9th brought a very strong gale, which lifted the topsoil in parts of Breckland. After a short, quiet interlude, cold easterlies on 14th gave way to mild southerlies. For the last ten days mainly dry, sunny, anti-cyclonic weather prevailed. Generally a mild, fairly dry month. A drake American Wigeon was found on the River Stour at Cattawade on 2nd and stayed for most of the month. The first summer visitors were not long in appearing - Sand Martins at both Loompit Lake (1) and Lackford Lakes (9) on the lOth. More surprisingly the first two House Martins were also at Lackford on the lOth. They were quickly followed by the first Northern Wheatear at Cavenham Heath NNR on 12th, the first Stone Curlew in the Breck on 16th and an early Ring Ouzel at Dunwich Heath on 18th. The 16th was a red letter day on the coast; a white-spotted Bluethroat on Orfordness, eclipsed by an Alpine Accentor found on the sluice at Minsmere, which stayed in the area until 19th. Two Common Crânes flew down the coast between Walberswick and Orfordness on 21 st, when a Serin was Garganey Su Gough discovered on Thorpeness Common. Suffolk's earliest ever Sedge Warbler reached Minsmere on 22nd and the small flock of Velvet Scoter, wintering off Sizewell, peaked at seven on the 24th. The first Barn Swallows came in on 25th, three at both Minsmere and Lackford Lakes and a pair of Garganey graced the River Lark at Lackford Bridge on 26th. There was a strong Firecrest passage in late month, typified by five at Minsmere on 28th and the final two good birds of March were a very early Wryneck on Thorpeness Common on 29th and a White Stork briefly seen at Outney Meadows on 30th. April April was a warm, sunny and fairly dry month. Warm settled weather became established from the Ist, assisting more early migrants. More changeable from 17th to 20th, then a very warm, dry speli until the 25th. The last five days were unsettled, with some rain and strong winds. With good weather at the start of the month more early migrants piled in; Redstart at Dunwich Heath on 1 st, Tree Pipit at Landguard on 2nd and Nightingales at Minsmere and 8


Review of the Year Dunwich on 3rd. The latter records equal Suffolk's earliest ever. The Serin was located again at Thorpeness on 4th and eight superb Hawfinches were to be seen in Sotterly Park on 7th. Migrant Ospreys reached both Minsmere and Trimley on 8th. A Red-rumped Swallow was seen briefly at Southwold on 11th and on 12th another drake American Wigeon arrived at Minsmere, to stay into June. Both Hobby (Thorpeness) and Cuckoo (Sizewell, Aldringham, Snape and Felixstowe) put in their first appearances on 16th, followed by an early Common Swift at North Warren on 19th. A Honey Buzzard over Felixstowe on 20th and the Temminck's Stint found at Orfordness on 21st were both Suffolk's earliest ever and probably came in on the same weather system and the Common Quail at Leiston on 22nd was also a rare April record. Six Eurasian Spoonbills came in off the sea and flew north over Dunwich Heath on 28th and on the 29th a Hoopoe was discovered on Hollesley Common. May The first two weeks were mostly dry but rather cool, with some night frosts and even coastal fog around the 10th. An Atlantic low on 13th brought wind and rain and then a short-lived spell of hot weather set in until 17th. Another vigorous low then produced very unsettled weather for the next week, with wind and rain and it remained changeable up to the 30th. The 31st was warm and sunny. A Black Stork, the first in Suffolk since 1998, spent an hour resting in the top of a pine tree in a large garden at Hawstead, near Bury St Edmunds, on the 1st. The first male Golden Oriole was in song in the poplar plantations at Lakenheath Fen on 6th, while the 7th produced a White Stork at Sternfield and an inland Temminck's Stint at the Mickle Mere. On the 8th a pair of Black-winged Stilts was discovered at Lakenheath Fen and the only Marsh Warbler of 2002 was in song at Thorpeness on 10th. Two more Temminck's Stints were at Orfordness on 11th and a fine Caspian Tern spent fifteen minutes on the north pools at North Warren on 12th. The first Spotted Flycatcher also came in on 12th - at Minsmere. Bluethroats reached Landguard on 13th and Orfordness on 18th and sandwiched in between was a Whiskered Tern at Lakenheath Washes on 16th and a female Red-footed Falcon at Orfordness on 17th. Two more Red-rumped Swallows were seen at Flixton on 19th and several Montagu's Harriers were found in the second half of the month. The Icterine Warbler in song at Blythburgh on 30th was the first of several. On 31st five Common Cranes were seen in flight at both Minsmere and Kingsfleet (on the R.Deben) and a Spotted Crake was calling from the reed beds at North Warren. June A dry, sunny start to the month and it was quite hot on the 2nd. Overnight on the 4/5th thunderstorms and heavy rain affected the region and the next week was cooler with showers. From the 12th conditions improved again and it was quite hot by the 17th. After more thunderstorms on 18th the last twelve days were mostly settled and dry. A bizarre record was a Raven flying over Ipswich on 2nd, the first in Suffolk since 1996. Also on 2nd, a European Bee-eater calling over Felixstowe was the first of three June records and it was followed by the only spring Red-backed Shrike, a female at Minsmere on 5th. An Alpine Swift flew north over Landguard on 6th and Icterine Warblers were trapped and ringed at Dunwich on 6th and Landguard on 7th. Six hundred Common Swifts were gathered at Trimley on 10th and the next day a Black Kite, the sole record of the year, was at Tuddenham St Martin. The long anticipated first nesting of Little Egrets in Suffolk occurred, with pairs at two 9


Suffolk Birci Report

2002

different sites. Great Bitterns showed a slight increase, to 18 booming males and no less than ten nests were built by Eurasian Spoonbills at one site, although the outcome is not known. A minimum of 34 pairs of Marsh Harrier nested along the coast and fledged at least 84 young; the Little Terns at Benacre sand bar had a good summer, fledging about 100 young and Cetti's Warblers bounced back to 33 singing males. In the Sandlings Dartford Warblers continued their rise, with 61 singing males located. Over in the Breck, Stone Curlews had an indifferent season, a pair of C o m m o n Buzzards nested again Little Egret Su Gough while Wood Larks declined, apparently as a result of the recent wetter summers. Golden Orioles are just about hanging on, with two pairs in the Fens. The state of the nesting populations of many of our commoner resident birds and summer visitors continues to give cause for concern. The second half of June was quieter, but a first summer Purple Heron arrived at Minsmere on 18th and was much watched during its seven week stay, spent mostly in the north marsh. Further European Bee-eaters were at the Dingle Marshes on 19th and Minsmere on 29th, a White Stork flew over Felixstowe on 24th and a Roseate Tern was at Minsmere on 30th. July The first half of the month was unsettled and cool, with quite frequent rain as low pressure systems approached from the west. From 13th an Azores high pressure ridge brought much warmer and sunnier conditions. More changeable from the 19th, with thundery showers and a severe hailstorm at Santon Downham on 20th. The last week was quite hot, but with thundery interludes, especially on 30th. Rainfall for the month was well above average. Five European Bee-eaters flew south past Minsmere on the 9th and there were singles at Kessingland on 4th and Landguard on 21st. A gathering of 418 Little Terns at Benacre Broad on 14th included a healthy 159 juveniles. A Roseate Tern was also at Benacre Broad on 27th and 28th and a quiet month was brought to a close by an adult Rosy Starling at Benacre Pits on 28th. August The first third of the month was very unsettled, warm but with frequent thunderstorms and localised flooding. Mid-month was quite hot, with thunderstorms again on 15th. Low pressure took over from 20th, with thundery showers and patchy mist on some mornings. The last week was mainly dry as a ridge of high pressure extended its influence over the region. No less than 73 Curlew Sandpipers were grounded on the scrape at Minsmere in heavy rain on the 1st and the same day 96 Greenshanks were on Havergate Island. On 2nd six Wood Sandpipers were at Minsmere and on 6th Green Sandpipers peaked at 19, also at Minsmere. Also on 6th there was a count of 36 Yellow-legged Gulls on the Blyth Estuary 10


Review of the Year and a Caspian Tern visited Havergate Island the following day. The first autumn Redbacked Shrike arrived at Landguard on 1 Ith, a juvenile Red-necked Phalarope dropped into Lakenheath Fen on 12th and the only Dotterei of the year was briefly at Landguard on 16th. A juvenile Black-necked Grebe visited Livermere Lake on 13th and Lackford Lakes from 18th, perhaps the same bird. An Icterine Warbier was a nice find in a garden at Boyton on 17th and the first of seven Barred Warbiers arrived at Dingle Marshes on 2Ist, followed by a Wryneck at Minsmere on 22nd, the first of nine. The count of 28 Eurasian Spoonbills on Orfordness on 2Ist is a record number for Britain, at least in recent times, and up to 118 Little Egrets were estimated to be present in the county during the month. Five Storm Petrels flew north off Southwold on 25th and 54 Yellow Wagtails feeding on Cavenham Heath on 28th was a high count for Suffolk. On 29th there was a female Red-footed Falcon at Oulton Dyke and a Red-necked Phalarope on Orfordness. The 3Ist was also diverse, with a Hoopoe at Gunton, 109 Little Gulls off Sizewell and a high count of 152 Common Crossbills at Santon Downham. September Moderate north-easterly winds at the start of the month produced some superò seawatching off the coast. There was a changeable speli from 5th to the 9th, with wind and rain particularly over 8/9th. From IOth onwards it became mainly dry and high pressure ridges dominated the rest of the month, bringing mostly dry, sunny and warm conditions. There were occasionai showery spells and some thunder on 26th. All attention was on the sea on Ist, with the largest ever movement of Sooty Shearwaters recorded off Suffolk; 340 north off the north-east coast, with at least nine Balearic Shearwaters also caught up in the passage. Another 224 Sooty Shearwaters passed north on 2nd and 3rd, together with about ten Leach's Petrels, 200 Gannets and two Cory's Shearwaters on 3rd.

11


Suffolk Birci Report 2002 A Great Egret appeared at Minsmere on 7th at the start of a three week stay and two early Jack Snipe were also there that day. The 9th was another good day for sea-watchers, with 28 Great Skuas off the north-east coast, a Sabine's Gull and a White-winged Black Tern seen off Southwold and a Grey Phalarope off Felixstowe. The 10th saw a marked fall of passerines along the coast, with at least 76 Pied Flycatchers in the Lowestoft area, Icterine Warbler at Sizewell and both Bluethroat and Red-breasted Flycatcher at Landguard. Another Bluethroat was at Felixstowe Ferry on 11th and on the 12th a Common Rosefinch was at Landguard and six Common Cranes were seen flying south there. There were also four more Red-backed Shrikes and three more Wrynecks in this period. However, the bird of the month was a Great Snipe at Corton Sewage Works on 13th, a great find and the first confirmed in Suffolk for 30 years. The next good birds were an early Yellow-browed Warbler at Gunton on 16th and a Spotted Crake at Minsmere on 17th. Seabirds were still moving through and the 23rd was an excellent day off Southwold, with a Grey Phalarope, 55 Arctic Skuas moving south and eight Long-tailed Skuas, including a flock of seven. A juvenile Black-headed Bunting was well-watched along the disused railway line at Gunton on 24th and 25th and a Pectoral Sandpiper was found at Gifford's Park on 24th. The final highlight of September came from the Breck, with a pre-migration gathering of 29 Stone Curlews on 30th. October The first ten days were similar to September, warm and mostly dry and sunny. Thereafter it became unsettled, often cold, very wet and windy. Lowestoft had 63mm of rain in 24 hours over 15/16th. The 25th brought gales and squally showers and a deep depression on 27th brought more rain and storm force winds, with widespread damage to trees and power lines. The roost of Little Egrets at Loompit Lake reached a peak of 50 on the 1st, a record count for a single Suffolk locality. With high pressure in charge, the month began quietly but a second Pectoral Sandpiper was found at Covehithe Broad on 6th and Brent Goose passage peaked on 8th with a strong movement all down the coast. Also on 8th a Yellowbrowed Warbler was at Landguard (the first of five) and this began a run of good birds. The 9th saw a Great Shearwater flying north off Southwold and a Great Grey Shrike at Sizewell and Minsmere (the first of four); the 10th a Dusky Warbler at Thorpeness, while the 12th produced Sabine's Gull at Minsmere and a Radde's Warbler trapped and ringed on Orfordness. A Honey Buzzard flying north at Gunton on 13th was surely moving in the wrong direction? A strong movement of Redwings was evident all down the coast on 16th and there was an excellent passage of Firecrests mid-month, with seven in a single tree in Belle Vue Park, Lowestoft on 15th and 15 at Southwold on 13th. Short-eared Owls were more in evidence than for several years and five at Shingle Street were much admired. By the 20th three Rough-legged Buzzards had reached the Sudbourne and Lantern Marshes area, where they were to spend the winter. A Pallas's Leaf Warbler was seen briefly on Dunwich Heath on 21 st. There was a run of Horned Lark records in mid-month, with a maximum of six at Lowestoft on 23rd. Also on 23rd, the drake Ferruginous Duck returned to winter (perhaps "hide" would be a better word) among the reedy pools at Minsmere. Five hundred Pinkfooted Geese in off the sea at Covehithe on 24th was a large flock for Suffolk. Wood Pigeon passage peaked with 14350 south at Landguard on 28th and a second Radde's Warbler was trapped on Orfordness on 30th. 12


Review of the Year November With Atlantic depressioni dominating it was very unsettled and very wet but mild throughout and winds were often strong and mainly from the south-west. Brief quieter interludes over 17/18th and 25/26th allowed some mist andfog to develop, then it was back to wind and rain for the last four days of the month. At least the counties wetlands received a good topping-up from one of the wettest Novembers in the past 50 years. The month got off to a good start with a second Pallas's Leaf Warbier at Shingle Street and a Dusky Warbier on Thorpeness Common on the Ist and three Red-necked Grebes flying south past Landguard on 3rd. Another Grey Phalarope was off Landguard on 1 Oth and four Water Pipits inland at Lakenheath Washes on 1 Ith were of note. A late Redbacked Shrike was on Sudbourne Marshes, also on 1 Ith. There was a significant oil spili off the coast mid-month, with many Red-throated Divers and Guillemots affected in the Sole Bay area. A very late Balearic Shearwater was seen offThorpeness on 15th and, perhaps the same bird, on 16th. Also on 16th a third Dusky Warbier was trapped and ringed at Hollesley Bay and a Long-eared Owl was at Landguard from the 20th onwards. The final Barn Swallow of the year flew past Landguard on 21 st. A Ione Bohemian Waxwing was found at Hazelwood Marshes on 23rd and small numbers of Little Auks were seen at several sites down the coast between 23rd and 25th. A fifth Great Grey Shrike was at Minsmere on 24th. December A changeable start to the month gave way to high pressure by the 5th, which brought a drier speli but with cold easterly winds until about the 13th. After rain on 14/15th, there were more cold easterlies until 19th. The last twelve days of the year were very wet, with frequent heavy rain, but the Christmas period stayed very mild throughout. Large roosts of Common Starlings provided a spectacular dusk sight at the Hen Reedbeds and Lackford Lakes throughout the month. On 8th there was a strong passage of Eurasian Wigeon (929) and Eurasian Teal (499) south past Landguard. Also on 8th 18 Whooper Swans were on the River Deben at Iken and 1000 Fieldfares Little Auk Peter Beeson were noted feeding on fallen apples in an orchard at Stonham Aspel. The lOth saw a first winter Glaucous Gull flying north past Kessingland. A Black-throated Diver on Heveningham Hall Lake on 15th was a rare inland find and no less than 650 Red-throated Divers were counted off Southwold on 19th. Between 17th and 19th the easterly winds brought in a few more Little Auks to the coast. Inland 150 Eurasian Siskins at Livermere Lake on 17th was a good count and a flock of 448 Yellowhammers in Northfield Wood, Onehouse on 22nd was easily the highest reported ali year. The year ended on a high note with a fourth, late Dusky Warbler present at Kessingland sewage works on 30th and 3Ist. 13


Suffolk Birci Report 2002

Mute Swans in Suffolk 2002 Mick Wright Summary With an increase of 20% since the last census in 1990, the 2002 eensus shows that the population of Mute Swans in Suffolk is clearly rising. The number of pairs recorded, either on territory, with a nest or with cygnets, totalled 191 (a substantial increase of 45% since 1990) and the number of non-breeding birds was found to be about 668. Introduction This national survey was jointly organised by the Wildfowl & Wetlands Trust, Swan Study Group, Scottish Ornithologists' Club and the British Trust for Ornithology. The survey was scheduled to take place in the summer of 2001 but was postponed due to the outbreak of Foot and Mouth disease throughout the UK and was subsequently carried out in 2002. In 1977 the Suffolk Ornithologists' Group (SOG) organised a countywide survey and thirteen years later, in 1990, a national survey was carried out. Both surveys achieved excellent coverage and in doing so set a high standard of recording, which in turn has provided a database on distribution, breeding and non-breeding numbers of Mute Swan in Suffolk. Following the period when Mute Swans were dying through lead poisoning, the subsequent banning of lead fishing weights, the effects of mild winters and cleaner waterways, this latest survey will enable an assessment of recovery. This report documents the Suffolk results for 2002 and compares the findings with previous surveys. Methods The methods were broadly similar to those used in 1977 and 1990. Ali suitable habitats in every 10 km square were to be surveyed. The fieldwork, ideally, was to be carried out in Aprii and May, but with an emphasis on surveying ali non-breeding birds in Aprii, because by May failed breeders might have deserted their territories to join non-breeding flocks. The recording form allowed for information from one essential and up to two additional, optional visits. Fieldworkers were asked to record the following: place/waterbody, habitat (from a list of codes supplied), six-figure grid reference, date and status. The status codes were as follows: T - pair on territory but without nest; N - pair with nest; B - pair with brood and D - pair known to have nested but failed or deserted. For non-breeding birds the number of birds present was recorded. The April WeBS count was used as an accurate assessment of the number of nonbreeders frequenting the tidal reaches of Suffolk estuaries. Results In keeping with the previous two major censuses of Mute Swans, excellent coverage was achieved with almost ail suitable habitat in Suffolk being searched. Those areas not checked were in TG40, tiny stretches of the Waveney (TM39), Ouse (TL98) and Stour (TL83) and three areas in the far west of the county in TL65, TL66 and TL67. The number of pairs recorded, either on territory, with a nest or with cygnets, totalled 191 and the number of non-breeding birds was found to be about 668 (see Table 1). Field workers reported that 12 nests (included in the figure of 191) were deserted or had failed for one reason or another. There were no Mute Swans recorded in the Suffolk 10km squares (part or complete) ofTL64, 75, 76, 85, 94 and 96 or in TM15, 16, 36 and 48. 14


Mute Swans in Suffolk 2002 Table 1. Mute Swan Results for 2002 (T) Territorial 70

(N) Nest 67

(B) Brood 54

(D) Deserted or Failed 12

Non-Breeding 668

The coastal strip, tidal estuaries and the main river valleys of the Waveney, Stour and Ouse were the favoured areas for Mute Swans. 80% of non-breeding birds were found in three habitats: water meadow/grazing marsh, rivers over three metres wide and on our estuaries. The largest gatherings of non-breeding birds were found at: Reydon Marshes [42], North Warren Marshes [28], Waveney River, TM39 [54], Martlesham Creek [31], Loompit Lake [47], Ipswich Wet Dock [33], Mistley Quay [72] and the River Stour, TL84 [33], 76% of breeding birds were found in three habitats: water meadow/grazing marsh, lakes/unlined reservoirs and rivers over three metres wide. The 10 km squares that supported the highest numbers of breeding pairs were: TM03, River Stour [22], TM46, Minsmere/Sizewell [15], TL68, Little Ouse [10] and TM23, River Orwell [9], See Maps 1, 2, 3 and 4 for numbers and distributions.

Map 1. Mute Swans by Non-breeding Birds

29-72

o

8-28

• •

2-7 0-1

Table 2. Main Habitats & Distribution of Breeding and Non-Breeding Mute Swans Habitat Codes

Breeding Pairs Birds

Non-Breeding

C6

Water meadow/grazing marsh

44

234

G3 G4

Lake/unlined reservoir Lined reservoir (lined with concrete etc, lacking emergent vegetation)

42

66

-

33

G7

River (more than 3m. wide)

59

H3

Estuary

-

(n.b. minor habitats have been excluded from the above table) 15

135 168


Suffolk Bird Report 2002

Map 2. Mute Swans by Territories

Map 3. Mute Swans by Broods

Discussion In the late 1970s and early 1980s, research found that ingestion of anglers' fishing weights had an impact on Mute Swan numbers through lead poisoning (Goode 1981, Birkhead 1982). Public concern and pressure from the Nature Conservancy Council (NCC), now known as English Nature (EN), led to the weights being banned in England and Wales. Soon after the ban, there was a marked increase in the Mute Swan population (Salmon et al. 1989). Improvements to the environment continued with a ban on wildfowlers using cartridges with lead shot in wetlands, the advent of cleaner waterways and the long succession of mild winters; ali factors that are leading to the upward trend in the population of Mute Swans. The Mute Swan is one of the easiest birds to find and to obtain accurate information on the number of territories, nests, broods and non-breeding birds. The coverage in Suffolk 16


Mute Swans in Suffolk 2002

population of 125 pairs (Marsh 1979). The next major census in 1990 found a small increase to 131 pairs, a rise of about 5% (Wright 1991 ). Twelve years on and the number of breeding pairs continues to rise; the 2002 census revealed a total of 191 pairs, a substantial increase of 45% since 1990. This latest census clearly shows how well the Mute Swans are doing in Suffolk. A comparison of the total numbers of Mute Swans recorded for the 1990 (873) and 2002 (1050) censuses, shows that the total population has increased by 20%. Table 3. Summary Results of Mute Swan Surveys Year

Coverage

* - 1955-56 * - 1961

Patchy

1977 * - 1978

Pairs

Non-breeders

66

466

Not carried out in Suffolk 125

98% [SOG survey] Not properly surveyed

* - 1983

56%

* - 1990

c. 90%

* - 2002

c. 90% * = National Breeding Surveys

131

611

191

668

Acknowledgements 1 would like to thank Martin Sandford and Carrie Howard for their technical help with the maps and Adam Gretton for his comments on an earlier draft. Thanks to the following fieldworkers: I. Barton, J. Brydson, A. Burrows, D. Casey, D. Clouting, J. Davis, A. Easton, R. Etheridge, P. Evans, A. Excell, D. Ford, J. and A. Garstang, D. Gibbs, N. Gibbons, J. Glazebrook, C. Gregory, T. Hoskins, C. Jakes, S. Jarvis, B. Last, R. Leavett, R. Macklin, B. Martin, S. Marginson, N. Mason, K. McColl, A. Miller, P. Murphy, R. Parfitt, J. Partridge, K. Philpott, S. Piotrowski, M. Pratt, N. and S. Rayment, N. Sills, N. Skinner, D. and J. Toomer, J. Turner, J. Walshe, P. Wilson, R. Wilton, G. Woodard and M. Wright. 17


Suffolk Birci Report 2002 References Birkhead, M.E. (1982). Causes of mortality in the Mute Swans Cygnus olor on the River Thames. J. Zool. Lond. 198: 15-25 Goode, D. (1981). Report of the Nature Conservancy Council's Working Group on lead poisoning in swans. NCC, London. Marsh, M. (1979). 1977 Mute Swan Survey. Suffolk Ornithologists ' Group Bulletin 36: 9-11. Salmon, D.G., Prys-Jones, R.P. & Kirby, J.S. (1989). Wildfowl and Wader Counts 19881989. The Wildfowl & Wetlands Trust, Slimbridge. Wright, M.T. (1991). Mute Swans in Suffolk 1990. Suffolk Birds 40: 14-18.

18


Breeding Waders ofWet Meadows Survey 2002 Mick Wright Summary The results of the 2002 survey reveal further dĂŠclinĂŠs in the populations of waders breeding in wet meadows, reflecting the continued dĂŠgradation of native wet grassland areas in Sufifolk. A total of 69 sites, covering around 7,800 hectares, were surveyed and approximately 570 pairs of waders located. Lapwing, with a total of 210 pairs, is the commonest wader, but had still declined since 1982 by almost 60%. Redshank is the second most numerous species with 136 pairs, a decrease of 14% since 1982. Snipe is now virtually extinct on these sites in Suffolk with only six drumming birds recorded, a staggering decline of 88% since 1982. However, Oystercatchers have increased by 95%, and Avocets by 65%, since 1982. Of the 69 sites surveyed, Yellow Wagtails were found at only eight and Meadow Pipits were present at 25 sites. Introduction A British Trust for Ornithology (BTO), Royal Society for the Protection of Birds (RSPB), and English Nature (EN) joint initiative first surveyed wading birds breeding on lowland wet grassland in 1982 to assess the extent of the remaining wet grasslands and their importance for breeding waders (Smith 1983). This new survey organised by the BTO and funded by RSPB, EN and the Department for Environment, Food & Rural Affairs (Defra), was carried out in 2002, the aim being to re-survey all the 1982 sites to assess the changes that have taken place in wet grassland habitats and the populations of wading birds they support. The opportunity was taken to survey any new wet grassland sites that had been created since 1982. Methods The survey required fieldworkers to make three visits to a site between mid-April and the end of June, with at least two weeks between visits. It was recommended that the first visit be carried out during April, the best time in which to establish the number of breeding Lapwings, and that visits were made between dawn and midday avoiding cold, wet or windy weather. The total number of waders and the number of pairs were recorded for each visit made. 'Pairs' were defined as either paired individuals, displaying/singing individuals, nests or broods, and other single birds not in flocks. The total number of waders of each species seen or heard was also recorded, which included all birds in flocks as well as those thought to be breeding or single birds. Other species recorded included ducks (except Mallard), Yellow Wagtails and Meadow Pipits. For ducks, the total number of adult birds (including males), with the number of males noted separately, was recorded. For Yellow Wagtails, the number of breeding pairs was recorded, and for Meadow Pipits, simply presence or absence. Habitat characteristics were also recorded as some sites held habitats other than wet grassland within the site boundary. For wading birds, the method for estimating the number of pairs was as follows: Oystercatcher and Lapwing - maximum number of individuals, mid-April to mid-June, divided by two. Snipe - number of drumming/chipping birds or highest count from May onwards, divided by two. Redshank - based on mean number of individuals, late April to end of May. 19


Suffolk Birci Report 2002 Curlew, Avocet, Ringed Piover and Little (Ringed) Piover based on number of pairs recorded. For wildfowl, the results are given as the maximum number of birds and males from the three visits. Results In Suffolk, fieldworkers achieved complete coverage of all the wet meadow target areas, a total of 69 sites covering approximately 7,803 hectares. The survey revealed very low numbers of breeding waders on many sites but, most worrying, almost half the sites, involving large areas of grassland, held no breeding waders at all. Approximately 570 pairs of waders were located. Table 1 shows the total number of pairs in 2002 and the total for those sites surveyed in both 1982 and 2002. The changes given clearly demonstrate the fortunes of breeding waders associated with wet grassland. Table 1. Breeding Wader totals for Suffolk 2002 (69 sites) and paired sites and % change Paired Sites Oystercatcher Lapwing

2002

1982

2002

% change

87

38

74

+95

210

295

121

-59 -88

Snipe

6

33

4

Curlew

3

8

Redshank

136

109

3 94

-14

Avocet

IH

52

86

+65

14

21

10

-52

Ringed Piover Little (Ringed) Piover

5

—

—

-63

—

Oystercatcher: Oystercatchers are not strongly associated with wet grassland but are adaptable in their choice of breeding habitat. However, some of the wet grassland sites included other habitats more favoured by these birds, especially those sites found within the coastal belt of Suffolk. Twenty-six sites held a total of 87 breeding pairs, with most of the sites having just one or two pairs. Havergate Island accounted for 27 pairs, Oxley Marshes eight pairs, Seafield Bay six pairs and Trimley Reserve six pairs. A summering flock of 96 was recorded on the Trimley Reserve. When comparing the data from paired sites between 1982 and 2002 this species has increased by no less than 95%. Little (Ringed) Piover: This species is a scarce breeding bird in Suffolk and it is almost non-existent in the east of the county. Despite suitable habitat within the 69 sites surveyed, only five breeding pairs were recorded; a single pair at Mickle Mere and two pairs at Shelley to Higham and the Nunnery Floods. Ringed Piover: Due to the variety of wetland habitats within the sites that were surveyed, a total of 14 pairs of Ringed Piover were found (with a decrease of 52% since 1982 on paired sites). These pairs were ail within the coastal belt. Havergate and Dingle Marshes held four pairs, Trimley Reserve and Seafield Bay two pairs and single pairs at Thorpeness Marshes and Boyton Marshes. Lapwing: Of the 69 sites surveyed only 37 held breeding birds. The number of breeding pairs recorded was 210. The sites supporting ten or more pairs were: Stanny Farm 24, 20


Breeding Waders of Wet Meadows Survey 2002 Trimley Reserve 18, North Warren (Thorpeness & Church Farm Marshes) 14, Hazelwood Marshes 13, Stratford to Higham and Shotley Marshes 12, Somerleyton and Blundeston Marshes ten. The data from paired sites between 1982 and 2002 indicates a decrease of 59%. Snipe: Although Snipe were recorded on passage at 23 sites, a total of only six drumming birds were recorded at four sites. This species is now virtually extinct on wet meadows in Suffolk. Curlew: Breeding pairs were found at only two sites. Redshank: Of the 69 sites surveyed only 25 held breeding birds. The number of breeding pairs recorded was 136. The sites supporting more than ten pairs were Havergate Island 19, Dingle Marshes 17, Shotley Marshes 13 and North Warren (Thorpeness & Church Farm Marshes) 11. A comparison of the data from paired sites between 1982 and 2002 shows that breeding numbers have decreased by 14%. Avocet: Eight sites supported 111 breeding pairs, with the number of birds seen totalling 249. The breeding sites were Havergate Island 54, Orfordness 24, Trimley Reserve 14, Hazelwood Marshes five, Dingle Marshes five, Tinker's Marsh four, Shotley Marshes three and Benacre Broad two. Black-tailed Godwit: Birds on passage were recorded at the Mickle Mere and Trimley Reserve, with over-summering recorded only at Trimley Marshes. Ruff: A passage bird was recorded at the Mickle Mere. Wildfowl: Wildfowl recorded (maximum counts) were: Shelduck 164 (50 males) at 22 sites, which included 38 at Trimley Reserve, 30 at Dingle Marshes and 15 at Thorpeness Grazing Marshes; Gadwall 135 (72 males) at 17 sites, which included 40 (22 males) at Trimley Reserve, 18 (7 males) between Lackford and Icklingham and 18 (10 males) at Mickle Mere; Tufted Duck 118 (72 males) at 19 sites which included 43 (27 males) at Trimley Reserve and 20 (12 males) at Botany Bay. Table 2. Wildfowl totals and males found at 69 Suffolk Wet Meadow Sites Shelduck

Wigeon

Gadwall

Teal

Pintail

Shoveler

Pochard

Tufted Duck

Garganey

Totals

164

2

135

32

3

26

5

118

3

Males

50

2

72

22

2

18

4

72

2

Teal and Shoveler were recorded at ten sites, with Trimley Reserve holding the highest concentrations. Pochards were found breeding at only two sites, Trimley Marshes and Reydon Marshes, and the only records for Wigeon and Pintail were from Trimley Reserve. Garganey, an uncommon summer visitor to Suffolk, were recorded at Boyton Marshes and Reydon Marshes. Two passerine species were surveyed. Single pairs ofYellow Wagtail were found at only eight sites and Meadow Pipits were recorded as present at 25 of the 69 sites surveyed. Discussion The last forty years have seen profound changes in agricultural management and an intensification of farmland practices (Shrubb 2003). The area of farmed arable land has increased by almost one million hectares since the early 1960s. Floodplain grasslands have been lost through drainage schemes, ecologically insensitive flood defence work, and the decline of mixed farming, increased urbanisation, etc. The habitat results from the 2002 21


Suffolk Birci Report 2002 survey clearly indicate that the loss and degradation of these grassland areas has continued. Since the 1982 survey, parts of many of the sites have been lost to arable, scrub, rank grassland or reeds. Many of the meadows were simply under-grazed and dry at a criticai time, the onset of the breeding season. Table 3. Lapwing and Redshank pairs at Key Sites Dingle Marshes Shotley Marshes Orfordness

Ha

ESA

Reserve

Lapwing

55 41

Y

Y

9

17

12

13

Y

Redshank

50

Y

Y

5

8

Havergate Island

108

Y

Y

8

19

Thorpeness/Church Farm

119

Y

Y

14

11

65

Y

Y

13

8

125

Y

95

Y

Hazelwood Marshes Stanny Farm Trimley Marshes Total area 2002 total (all sites) % o f total

Y

24

8

18

9

658

103

93

7803

210

136

8%

49%

68%

A large proportion of waders breeding on grassland areas are now found at only a few key sites in Suffolk, most of which are either nature reserves or are within Environmentally Sensitive Areas (ESAs). Worryingly, eight sites, accounting for an area of only 658 ha out of a possible 7,803 ha, supported 49% and 68% of the Lapwing and Redshank breeding populations respectively (see Table 3). Many ESA prescriptions are designed to benefit breeding waders but whether they actually do so varies greatly between sites. A comparison of the results from 22 wet meadow sites, surveyed in 1982, with those from the 2002 survey, that are now all managed under Suffolk River Valley ESA agreements, shows that the number of Lapwing pairs has declined from 182 to 66; an alarming decline of 64%. However, over the same period, the number of Redshank pairs has remained relatively stable at around 80. Waders have fared much better at some sites than others. The BTO is hoping to secure further funding from RSPB, Defra and EN to analyse data from this survey in more detail and gain some insight into the reasons for this. A survey of breeding waders and other wildfowl on the coastal marshes and saltings of Suffolk in 1988 and 1989 found that a third of all the Redshank, 25 pairs of Snipe and approximately 100 pairs of Lapwing were on the Blyth grazing marshes (Holzer & Beardall et al. 1991). Just over fifteen years later these same areas are virtually devoid of breeding - —^ "B waders - Redshank, six pairs; Lapwing, ten pairs, Pied Avocet Peter Beeson

a n d

n o

Snipe.

22


Breeding Waders of Wet Meadows Survey 2002 Sites surveyed Botany Bay TL700865, Norah Hanbury-Kelk Memorial Meadows TL704741, Hockwold TL745870, Icklingham TL750735, Weeting Heath TL765872, Lackford to Icklingham TL788709, Flempton Green TL815704, Santon Downham TL815880 & TL815881, Long Melford TL850450, Bamham Little Ouse TL870798, Mickle Mere TL938694, Thorington St. TM 015348, Redgrave & Lopham Fen TM050798, Stratford to Higham TM038345, Flatford to Stratford TM060335, Dove Thornham Magna TM 100700, Roydon Fen TM 100797, Seafield Bay TM 120334, Holbrook to Stutton Ness TM 155335, Dove EyeHoxneTM 159749, Brockdish Oakley TM 190782, Levington TM236389, Shotley Marshes TM247352, Trimley Marshes TM257363, Trimley Reserve TM258356, Mill River Kirton TM281415, Framlingham Mere TM284638, Earsham to Wortwell TM305871, Bungay to Earsham TM330895, Melton to Ash Corner TM315525, Lower Hacheston TM315564, Loudham & area TM315555, Oxley Marshes TM368431, Boyton & Hollesley Marshes TM390461, Boyton Marshes TM390470, Chantry Marshes TM410470, Havergate Island TM410470, Middleton, Waveney TM430680, Blyth Valley Marshes site 1 TM430762, Hazelwood Marshes TM435575, Blyth Valley Marshes site 2 TM436755, Orford TM440495, Stanny Farm TM440560, Blyth Valley Marshes site 3 TM445750, Union Marshes TM446754, Aldeburgh Marshes TM453562, Church Farm Marshes TM465578, Thorpeness Grazing Marsh TM465590, Minsmere Levels TM465660, East Bridge Middleton TM445675, Sizewell Belts TM467638, Dingle Marshes TM480724, Tinker's Marsh TM483760, Reydon Marshes TM485765, Town Marshes Reydon TM500755, Busscreek Marsh Reydon TM504769, Somerleyton & Blundeston Marshes TM500960, Oulton Marsh TM505940, Church Farm Marshes TM516852, Benacre Broad TM534828, Beach Farm Marshes TM525846, Kessingland Levels TM525852, Nunnery Floods and Shelley to Higham. Acknowledgements I would like to thank Juliet Vickery for her constructive comments. My thanks also to the fieldworkers who gave up their precious free-time to help gather the data for this paper: Jim Askins, Adam Burrows, Cyril Burton, Joe Davis, Marilyn Dohadway, Andrew Easton, Reg Etheridge, Andrew Excell, Vicky Francis, Graeme Garner, John Glazebrook, Adam Gretton, Bridget Griffin, Ian Hay, Steve Holloway, Tony Howe, Peter Lack, Russell Leavett, Steve Piotrowski, Rob Macklin, John Marchant, Bruce Martin, Tony Martin, Alan Miller, Mervyn Miller, Andy Needle, Ian Paradine, John Partridge, Roy Patrick, David Pearson, Carl Powell, Mike Pratt, Derek Rothery, Terence Sandy, John Turner, Darren Underwood, Rick Vonk, Rodney West, A.M. Wilson, Geoff Woodward, Reg Woodard, Malcolm Wright and Mick Wright. Thanks also to the many landowners who granted access permission. References Holzer, T.C., Beardall, C.H., Dryden, R.C. & West, R.B. 1992. Breeding waders and other waterfowl on the coastal marshes and saltings of Suffolk in 1988 and 1989, Suffolk Birds 1992: 19-28. Shrubb, M. 2003. Birds, scythes and combines: a history of birds and agricultural change. Cambridge: CUP. Smith, K.W. 1983. The status and distribution of waders breeding on wet lowland grassland in England and Wales. Bird Study 30: 177-192.

23


Suffolk Birci Report 2002

Racial, Age and Sex Composition of Snow Buntings Plectrophenax nivalis Wintering in the Felixstowe Area of Suffolk Nigel Odin Over three winters from early 1997 to early 1999, Snow Buntings were trapped at either Felixstowe Ferry or Landguard Point. An initial appraisal of the birds trapped in early 1997 appeared in The Harrier (Odin 1997). A total of 249 individuals were trapped for ringing, including one individual which returned for consecutive winters (114 in 1996/97, 85 in 1997/98 and 51 in 1998/99). Using plumage characteristics described by Banks et al. (1990), with revisions by Smith (1996), the resulting racial, age and sex composition was: P. n. insulae

P. n. nivalis

Indeterminate

Totals

First-winter males First-winter females Adult males Adult females Unaged males Unaged females First-winter unsexed

49 111 1 17 2 2 0

13 17 1 2 0 0 0

1 27 0 4 0 1 1

63 155 2 23 2 3 1

Totals

182

33

34

249

Using only birds of known race, 85% were of the Icelandic race P. n. insulae (range between winters 77% to 89%) and 15% were of the nominate form P. n. nivalis (range 11% to 23%). 64% of the flocks were first-winter females (range 56% to 78%), 26% first-winter males (range 22% to 27%), 9% adult females (range 1% to 14%) and adult males less than 1%. The racial, age and sex composition of flocks thus varied between winters, with more adults venturing to Suffolk in the first two years of the study than the last. Of 114 birds trapped in the initial winter, none were caught in the following winter in Felixstowe, although one young male was subsequently trapped at Salthouse on the north Norfolk coast, as an adult. Of 85 birds trapped in the second winter of the study, one returned as an adult female the following winter and was the only adult trapped that winter. Of 50 new birds trapped in that third winter, two individuals caught on 30th January were retrapped on their spring migration, one at Salthouse 109 km to the north on 20th February and the other at South Gare, Cleveland, 337 km to the NNW on 27th February. No further recoveries resulted from the 249 birds ringed. These results fit in with other studies in the southern North Sea (see Smith in Werham et al. 2002), except for a lower recapture rate. This may be because the study site is towards the southern end of the species' wintering range. 90% of birds trapped were first-winter birds and as such the numbers seen in Suffolk will be dependent on the previous summer's nesting success, particularly in Iceland, where most birds probably originate. Other factors influencing the numbers in Felixstowe in any one winter may be population pressure and food availability further north along North Sea coasts, with fewer birds coming this far south in years of poorer breeding success, lower population numbers and when a plentiful food supply is available further north. It is not known where birds of the nominate race originate (Smith in Wernham et al. 2002). 24


Racial, Age and Sex Composition of Snow Buntings My thanks to Mike Marsh for help with feeding the birds and commenting on the above. This study was funded by Landguard Bird Observatory, its members and friends. References: Banks, K.W., Clark, H., Mackay, S.G. & Sellers, R.M. ( 1990). Ageing, sexing and racing Snow Buntings in winter plumage. Ringers Bulletin, 7: 84-87. Odin, N. (1997). Snow Buntings at Felixstowe Ferry - early 1997. The Harrier 111: 7-9. Smith, R.D. (1996). Racial composition of breeding and wintering Snow Buntings Plectrophenax nivalis in the north-east Scottish uplands. Ringing and Migration, 17, 123-136. Smith, R. in: Wernham, C.V, Toms, M.P., Marchant, J.H., Clark, J.A., Siriwardena, G.M. & Baillie, S.R. (eds). (2002) The Migration Atlas: movements of the birds of Britain and Ireland. T. & A.D. Poyser, London.

25


Suffolk Birci Report 2002

Roosting Behaviour of Common Swift Malcolm Wright On the evening of 10th June 1994, many Common Swifts Apus apus were feeding over the lakes at Lackford Wildfowl Reserve (now known as Lackford Lakes) in West Suffolk. As dusk approached, numbers increased dramatically and several thousand were present at low level, wheeling at high speed just above the willows and sallows along the lake margins. At dawn the next morning, five members of the Lackford Ringing Group (Anne Brenchley, Simon Evans, Tony Howe, Darren Underwood and Malcolm Wright) were on the reserve to carry out Constant Effort Site ringing. At first light no swifts were visible, but at about 04.30 GMT we looked up to see several hundred birds in the sky above us. Instead of flying and gliding around in the usual rapid manner, each bird was maintaining a more or less static position in the sky, on gently flapping wings. The birds were mostly between 100 metres and 200 metres above the ground, with a small number higher than this, and they were not in a close flock but spaced out, with some birds visible through binoculars up to 800 metres away. All the birds were headed in the same northerly direction (into the wind) and were, in effect, hovering, but with some slight movement forward or up and down from time to time. Weather conditions were fine and sunny with a largely clear sky and a gentle north breeze, about force 2. The air temperature was mild, about 12°C, and there had been no precipitation in the previous 24 hours. This same hovering behaviour continued for a further 45 minutes. The swifts appeared quite comfortable in maintaining their positions throughout this period; their wing beats were relatively gentle and I remember thinking that they were almost like marionettes, hanging in the sky as if suspended on invisible wires. We observed the swifts carefully through binoculars and there appeared to us to be no question of this being some sort of unusual feeding activity; rather they appeared to be roosting or resting on the wing. They were completely silent throughout this period. At about 05.15 GMT we suddenly noticed that the hovering had ceased and that normal feeding and aerial flight had been resumed. Many of the birds had descended to near ground level again and 14 were caught in mist nets. It was an astonishing sight and we all speculated as to what the swifts were doing. It has long been known (and proven by means of radar studies) that many Common Swifts spend the night on the wing over breeding areas in Europe, ascending up to 3000 metres (10000 feet) into the sky. Was what we had observed over Lackford the normal roosting mode of Common Swifts at high altitude during the night and for some reason on this particular morning had the birds roosted well after dawn and descended much closer to the ground than is usual? Subsequently we checked the literature and could find no reference whatsoever to any behaviour resembling that we had seen. It seems that what we saw that morning at Lackford was unique, or at least if anyone had seen such behaviour before then it had gone unreported. We wrote up the observation and submitted it to British Birds and it was eventually published in their notes section in the March 2000 edition. The following year, in the April 2001 edition, British Birds published a most interesting note from Prof. C. M. Perrins of the Edward Grey Institute, Oxford, in response to our note. He related a conversation with the late Prof. Glen Schaefer, who had made a number of studies of birds by using radar. Some of these involved the use of an S-band fire control radar, which had a very narrow beam with which he could 'lock 26


Roosting Behaviour

of Common

Swift

on' to individuai birds in flight. He was trying to see whether he could pick up the wing beat pattern of the individuals, with the hope of being able to identify them. Perrins asked Schaefer whether he had looked at any possible swifts with his radar. He replied that he had, but that he was puzzled by the observations. The birds which he thought to be swifts did not apparently move in his radar beam. The only movement that he could detect was drifting in the direction of, and with the speed of, the prevailing wind. He calculated that, at the altitude at which the swifts were 'roosting', he would have been able to observe their movements if they were flying normally. The only explanation which he could think of was that the birds were flying in tight circles; if a bird circled within a radius of about 10 métrés he would not have been able to detect any movement with his equipment. This he thought was unlikely and was probably why he never published the observations. Perrins goes on to state that there is another radar study with similar findings. Eastwood (1967), in an account of the vespers flight of swifts, also stated that the 'angelic hosts' are virtually static; no progress is made in any direction (other than a seaward drift). Eastwood also quoted Schaefer's study of swifts, saying that Schaefer found a wingbeat frequency of seven per second at night, compared with ten per second during the day. Perrins concludes his note by saying that " the visual account by Wright et al. seems completely in line with Eastwood's and Schaefer's radar observations, though how such a narrow-winged bird as a swift can actually 'hover' remains to be explained. It would clearly be worthwhile for someone with m o d e m equipment to try to find out more about the Common Swift's unusual nocturnal habits". So it seems that when the swifts ascend screaming into the sky at dusk on a summer's evening, they ascend up to two or three thousand métrés and may spend up to six hours hovering high in the atmosphère. But there is stili so much that we do not know about their habits, because they are so difficult to observe at altitude. Is this just one strategy that they use or are there others? And what do they do outside the breeding season? According to the literature, no one has ever found Common Swifts roosting at ground level in sub-Saharan Africa and they are thought to roost aerially there too. Near the equator the nights are almost 12 hours long, so do they spend up to 12 hours hovering high over the savanahs or rain forests? And do any other species of swift use a similar strategy? There is undoubtedly a good PhD. study here for a bright Student who can get hold of the right radar equipment. Since the two notes were published, I have found one further clue in the literature. In David Lack's classic monograph, Swifts in a Tower, there is a most interesting chapter on "Swifts at Night". In it he relates a fascinating observation made by a French airman during the 1914-1918 war near Arras in northern France. "One night he was on a special opération on the Vosges front which involved climbing to 14500 feet above the French lines and then gliding down with engines shut off over the enemy lines. 'As we came to about 10000 feet, gliding in close spirals with a light wind against us, and with a full moon, we suddenly found ourselves among a stränge flight of birds which seemed to be motionless, (my italics) or at least showed no noticeable reaction. They were widely scattered and only a few yards below the aircraft, showing up against a white sea of clouds underneath. None was visible above us. We were soon in the middle of the flock, in two instances birds were caught and on the following day I found one of them in the machine. It was an adult male swift ". It appears from this account that the French airman had chanced upon a flock of hovering swifts, two miles high above the First World War trenches.

27


Suffolk Birci Report 2002 References Eastwood, E. 1967. Radar Ornithology. London. Lack, D. 1956. Swifts in a Tower. London. Petrins, C.M., 2001. Roosting Behaviour of Common Swifts. Brit. Birds. 94: 204-205 Schaefer, G.W. 1966. The study of bird echoes using a tracking radar. Proc. I4th Int. Orn. Congress. Wright, M., Brenchley, A., Evans, S., Howe, T., & Underwood, D. 2000. Roosting Behaviour of Common Swifts. Brit. Birds. 93: 145.

28

Suffolk Birds 2002 Part 1  

Volume 52

Read more
Read more
Similar to
Popular now
Just for you