Small blue survey 2012

2012 Small Blue Survey

Small Blue Survey

By Iain Cowe February 2013

Contents 1. Introduction 2. Berwickshire Coast North 3. Berwickshire Coast South 4. Berwick Upon Tweed North 5. Berwick Upon Tweed South 6. The East Lothian Question 7. Inland sites 2013

8. Plans for 2013 9. Summing up

1

INTRODUCTION

After last years surveys on the Berwickshire and Northumberland coast, the following are the results of those surveys.

A clearer picture of possible and actual Small Blue sites was achieved, but as ever there will always be more to do.

Thanks to everyone who took part directly or indirectly, much appreciated. Having more eyes out there looking for Small Blue and the food plant Kidney Vetch is and was a huge help.

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BERWICKSHIRE COAST NORTH

The Berwickshire Coast North section stretches from Bilsdean and Cove in the north too Coldingham in the south. Thus far no Small Blue have been found in the section, and there is little in the way of decent habitat apart from Brander Heugh (illustrated below), StAbbs Head and Coldingham Bay Homeli Knoll.

Brander Heugh is a very likely spot, yet its isolation would very probably hinder any chance of colonisation...which is a pity. St Abbs Head is still under recorded and that needs fixing‌so little can be said until a proper search is done. Coldingham Bay and Homeli Knoll has seemingly perfect habitat with lots of flowering vetch‌ Small Blue still possible here, though it has been a good number of years since they were last seen here.

Searches were carried out in the north at Cove, Pease Bay, Greenheugh and Ramsheugh yielding little in the way of Kidney Vetch. A few sorties were also made out to Redheugh, Siccar Point and Fast Castle with no positive KV sightings.

Brander Heugh

A rich flourish of KV spills down a zig zag track way to the shore.

Photos by Barry Prater.

Greenheugh,Ramsheugh

A sparse few patches on the Northern sections either side of the Pease Bay. Photos by Nick Morgan.

Coldingham Bay

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BERWICKSHIRE COAST SOUTH SECTION

This is a very rich section from Yellowcraig Head and Linkim Shore in the north to Lamberton in the south. An almost continuous seam of Vetch in varying degrees of density meaning that colonisation from the known sites is very possible.

Notable sights are many and from North to south include, Yellowcraig Head, Linkim Shore(south), Linkim Kip to Callercove Point, Killiedraught Bay, Hairy Ness, Fort Point, Eyemouth Bay, Gunsgreen, Ramfauds too Daring, Blaikie Heugh at Hurkers Haven, Breeches too Partanhall. It is at Partanhall where there is quite a gap of a few kilometres before the KV returns at Catcairn, Hilton Bay and Lamberton Beach then fizzling out at Tods Loup. Most of the KV recorded was known from previous botanical surveys, any new records were of very small plant groupings, yet, significant enough to afford the butterfly a stepping stone from one site to another‌in theory.

Yellowcraig Head

Linkim Shore

Hairy Ness

Kings Gardens Small Blue Site The Kings Gardens site north of Partanhall, Burnmouth was discovered – rediscovered in 2011. The site hugs the shoreline below the steep grass slopes and runs the length of approx. 800 metres from the cottages at Partanhall along a rock and pebble strewn shoreline to Breeches in the north. There is a vast amount of Kidney Vetch on the upper and lower slopes as well as the high tide line. In 2012 a maximum count of 16 Small Blue adults were recorded June 13th. It is quite a complex site to record as most of the terrain is quite simply inaccessible. The tides make surveying quite tricky, and on top of that the site loses the full sun quite early in the day…about 2pm in peak season…so the butterflies tend to be on the wing much earlier in the day. As yet there are no solid historical records for this particular site, though, it seems likely that they have been observed here before as the colony is quite visible.

The challenge at this site is expansion…possible colonisation. To the south it looks unlikely as there is little in the way of food plant beyond Partanhall. To the north however there is a very likely spot that lies just 800 metres away at Blaikie Heugh. Can the Small Blue make that leap? Only time will tell. If they did colonise Blaikie…then…a further expansion north to Eyemouth would it seem be quite likely considering the amount of food plant available.

In 2012 there were 9 records of Small Blue at Kings Gardens site culminating in a total of 37 individual adult butterflies between 24th May to the 20th of June. No eggs or larvae were recorded.

Comparing that with 2011, there were 3 records, culminating in a total of 15 individuals..all visits were made in mid June. Eggs were recorded.

EYEMOUTH PENINSULA In June 2010 Barry Prater found 1 adult Small Blue on the cliffside base of Eyemouth Bay. A few days later he returned and saw yet another Small Blue adult. Getting photographs on both occasions it seemed to me at least that these were quite separate individuals. Despite numerous searches since we have been unable to locate any through 2011 and 2012…so…where are they now? Its quite frustrating.

As for habitat there is plenty, and after surveying the peninsula in 2012 found very large amounts of Kidney Vetch along the north beach cliffs running up to Fort Point and on sporadically towards Hairy Ness where there is copious amounts of food plant. Yet no butterfly since Barrys sightings. Kidney Vetch is quite constant from this Peninsula north towards Linkim Shore…a distance of roughly one and a half miles following the coast. In theory we could find Small Blue tucked away anywhere from point to point. As I said it is very frustrating not to be able to get to the bottom of this…but…I feel that we will uncover them again soon.

All photos by Barry Prater from Eyemouth Bay These are the photos Barry took of the Small Blue individuals on 2 separate occasions, firstly June 16th, then June 22nd. Note the abdomen size of both butterflies. I am convinced enough that they are female first photo, and male 2nd.

CATCAIRN SMALL BLUE SITE The Catcairn site situated south of Burnmouth just of the Berwickshire coastal path has been monitored closely since 2007. In 2007 and 2008 only a few butterflies were seen in each season. During 2009 we discovered a good few more, and that can be owed to being a little more adventurous in exploring the steep scree and boulder slope. In 2010 it seemed that the colony were a lot more strung out than we had first thought with quite a few individuals being found quite a way from the main core site. 2011 pretty much confirmed that. In 2012 a new dynamic was introduced to us by the relaxation of sheep grazing to the south of Catcairn. It was very obvious almost immediately that the Small Blue had taken advantage of the cessation in grazing and had spread south quite significantly in numbers utilising all available Kidney Vetch heads.

In 2012 I had 15 records of 161 adult butterflies between 16th May through to the 20th June peaking on 26th May with a count of 57. There were 11 larvae found from 26th July to the 16th August. Eggs were not counted, but there were many hatched and unhatched observed from the Northern extent to the southern extent. See map.

2011 comparison reads 11 records of 67 adult Small Blue between May 9th to the 13th of June peaking on May 18th with 19 adults counted. 6 larvae were counted on the 26th July. 18 eggs counted on the 14th May and 14 eggs on a single plant on the 18th of May. From that comparison you may believe that 2012 was a better year than 2011‌its not as simple as that.

Timing and weather and how often you visit and how long the visit do skew results. The flight period in 2012 was blessed with a window of decent weather unlike 2011. But I feel that the butterfly is very much better than we humans at adapting to certain conditions. And it is easier for us not to bother going out on a less than hopeful day.

The most fascinating Small Blue discoveries are to made on the periphery of main core sites, where the very last straggling plants are found. Its there that you can see clear evidence of a struggle to expand. It was on the 20th of June while scouting the cliffs north of Burnmouth when I received a mobile phone call from my brother who was making his way up the coast from Lamberton and came across an adult Small Blue well south of where we were used to seeing them. I immediately tore south to Catcairn and on to Hilton Bay. Just to the north of Lamberton Beach I met my brother whom had lost site of the butterfly…so we waited…and waited. As if by magic the little blue skipped into the air right in front of us..a female, battered and worn, but very capable. Where had she been? Had she been laying eggs? We searched all available heads….nothing. Still the little female flipped and skipped but never committing herself to any particular spot. I pretty much gave up, and slumped by a patch of Kidney Vetch, and as I sat she circled around me, landed on my arm then fluttered down to the very patch of Vetch in front of my eyes and layed a few eggs…astonishing!! On closer inspection I could see that she had been very busy, and for one reason or another this was her chosen spot. There were several eggs spread over several heads…now that was good…but…returning here and seeing her offspring mature into healthy caterpillars would be something else.

It was the 16th August that I returned to the spot that little female had been a few months ago…and with amazement her offspring were all very much alive and well, chomping hungrily on those seemingly tasty Anthers….I just cant wait to see the finished articles in May this year.

The larvae are very well camouflaged among the Kidney Vetch heads and take a great deal of patience to spot.

Once you have your eye in, its fairly easy to spot more…fairly easy…. Above left the most southerly female of the Catcairn clan and her offspring.

OTHER SITES OF NOTE IN THE BERWICKSHIRE COAST SOUTH SECTION There are many worthy sites to look closely at in the south section. Starting at Yellowcraig Head in the north.

I would never have found this little gem of incredible habitat if it had not been for Michael Braithwaites superb book “ A Botanical Tour of Berwickshire” Hidden away from the coastal path lies a most incredible little micro habitat of rockpools fringed with Thrift, Birds Foot Trefoil and Kidney Vetch and a myriad of other seldom seen botanical beauties. It was a pity that the weather during my brief visit was leaving little to be desired…yet…I am glad to have this little spot to enjoy one sunny day. The shelter and hidden nooks of this site make it Small Blue worthy….and worthy of many more visits.

Yellowcraig Head

Linkim Shore is certainly worthwhile, much of the obvious Kidney Vetch is in the south end of the bay next to the coastal footpath. However there is quite a bit more on the south cliff face and around the seaward side in deep gulleys towards Linkim Kip. From here a continuous yellow ribbon winds itself over craggy outcrops and sheer drops to Callercove Point. Callercove Point is a seldom used section of coastal footpath and here a great drift of Vetches including Kidney, Wood and Birds Foot on the north side with a south facing bias seem very, very likely. Killiedraught Bay just north of Eyemouth has minimal Kidney Vetch but maximum potential with much shelter and frequent erosion inviting new seedlings to develop.

South of Eyemouth Harbor and above Gunsgreen House lies a mosaic of scrapes, weed strewn bankings bursting with plant anomalies including offcourse Kidney Vetch in healthy patches. From Ramfauds all the way south to Blaikie Heugh a huge amount of Kidney Vetch can be seen in a very herb rich strip bordering the golf course. Agate Point, Whalt Point, Scout Point and Daring being a few of the waypoints of interest along the way.

Blaikie Heugh There are no specific records for Blaikie Heugh concerning Small Blue past or present, but this site has surely housed Small Blue at least once in its lifetime. It sits on rocky platform overlooking Hurkers Haven and Fancove and apart from being breathtakingly picturesque it is jam packed full of wildlife….but why no Small Blue I wonder. The Kidney Vetch here is quite copious and maybe its lofty position could prevent it from colonisation from the nearby Kings Gardens site. Blaikie is very often visited throughout the season…fingers crossed.

4

BERWICK UPON TWEED NORTH

The Berwick Upon Tweed North section is a short but useful area of coastal grassland that stretches from south of Marshall Meadows to Needles Eye. The grassland is quite rank in places, but where it is less so Kidney Vetch is flourishing. Concentrations of the plant can be found at Needles Eye and at the railway crossing where the ground is quite compacted and thin. There are quite a few decent embankments that could shelter a colony of Small Blue in theory. I have checked Kidney Vetch heads for evidence of Small Blue for the past 3 years on this section without luck. Marshall Meadows itself has a deep ravine that looks interesting enough, but‌a little dangerous perhaps to survey. Along the clifftops there are flushes of Kidney Vetch that do not extend towards the seaward side. A little erosion in places has and is taking place. If Small Blue were to colonise from further north, then I could only expect that to be via the most direct route possible, the main east coast rail line. There is Kidney Vetch on the rail line in patches but how far north that extends is unknown. Not coincidentally the best patches of Kidney Vetch are growing where Yellow Rattle is holding the thicker sward back. North of Marshall Meadows to the border is unknown as it seems to be quite difficult to impossible to survey.

Map not to be taken to literally.

Merely a representation of KV position and density from Needles Eye to Marshall Meadows.

Most of the butterfly species seen here are heavier grassland specialists. Meadow Brown and Ringlet can be numerous. Also the recent appearance of Large and Small Skipper point to this section becoming unsuitable for species such as Common Blue, Small Heath and ultimately a possible Small Blue colonistaion.

5

BERWICK UPON TWEED SOUTH SECTION

This section covers some 3 miles of coast line from Spittal in the north to Cheswick in the south. From Spittal to Seahouse the Kidney Vetch is very patchy, but where it exists it is very useful. The area at This the moment is being grazed by cattle and owing to the weather last year the cattle had chopped up the ground quite badly, on top of the erosion that is occurring. Prime ground for Kidney Vetch seedlings to establish. The best of the patches of food plant can be found on the Redshin banks towards the lower slopes. This area is quite isolated though from anything further north. It is to the south of Seahouse on the Cocklawburn dune systems that there is an almost overabundance of suitable habitat.

Spittlal to Seahouse Section

Dune craters are very good spots to have a beach party, almost every crater has an ex campfire in the middle of it. Apart from that these craters are jam packed with Kidney Vetch and Purple Milk Vetch. Lime spoils to the south of the section are just superb and equally full of botanical delights.

Cocklawburn and Cheswick

I have visited the Cheswick and Cocklawburn area twice in 2011 and once last year, and was never lucky enough to get one decent days weather to match the incredible beauty of the place. There are tons of species potentially here yet they are just not, at least on the days I visited, easy to find. We initially had thought that there was little in the way of Kidney Vetch still in existence throughout the dune and lime spoil system..but there is plenty and more. Just does not seem right that with so much suitable habitat there are apparently no Small Blue butterfly present. Molly Hardie gathered an incredible number of records from the site this last year to give a picture of just how widespread the plant is at least. I will certainly look at the site again this year, just in case I missed something. There are plenty of other butterfly species present as well as a plethora of day flying moths..even some of the night flyers can be easily found by day.

The only evidence of Small Blue historically is a scratchy entry that suggested that Small Blue were present south of Berwick during the war years 39-45. It was not though divulged where south of Berwick‌it was only supposed that it would be Cocklawburn‌.south of Berwick in theory could be anywhere between Berwick and Bamburgh. Whatever the truth, we will probably never know. I may try as well as Cocklawburn a little further south at Goswick next. Roger Norman wrote to me saying that he did a quick recce at Ross Sands without success. Ron McBeath remarked that Kidney Vetch was present on a recent SWT outing to Holy Island. Anything is worth a try. I never got any reports from south of Bamburgh at Red Barns Links still one to cover one day.

6

THE EAST LOTHIAN QUESTION

I have not seen any historical records for East Lothian concerning Small Blue butterflies. In fact I have not any idea what the possibilities are in the region. From Bilsdean to Dunbar would be quite a decent area to search and record at least the food plant and perhaps get a picture of the likelihood of a future colony . To be honest if they are not there already the chances of colonisation from Berwickshire are not really on considering the sparse amounts from Lumsdaine north. The only hope I can give is the amount of industrial landscaping that has taken place over the past 50 years. Quarries excavations…anything and anywhere that shifts soil…it’s perhaps the only chance of a possible introduction of the food plant or more remotely the butterfly itself. Yes….very remote…but never say never. If anyone would like to carry out a survey of that stretch of coastline for Kidney Vetch I would be very interested to hear about what you find.

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INLAND SITES 2013

Inland sites have pretty much been ignored in the Borders at least ever since the demise of the colonies at Hawick. Kidney Vetch is becoming very scarce inland. Most of the railway sites have scrubbed over and riverbank sites are heading the same way. Some quarries still have Kidney Vetch and a few of the Berwickshire volcanic plugs have a sprinkling. I will write up an area search of known sites in the Borders in time for May flight time for anyone who wishes to go out and have a look at the few remaining viable sights…I may even haul myself over to Hawick and take a look at the remnants of what was…such a sad story to hear of a butterflies extinction.

8

PLANS FOR 2013

Plans are just to keep on keeping on. Still plenty to do regarding surveying. St Abbs Head is priority this season. Ross Point yet unexplored to the south of Burnmouth. I have yet to visit Lumsdaine shore after missing it last season. South of Berwick I would like to look at Cocklawburn again as well as this time Goswick.

Anyone willing to get out there and do a bit of recording at the known Small Blue sites and beyond are welcome to as usual…just report everything and anything to me. It is important that as many people as possible get involved in some way, keeping an eye on what we have at the moment. There is a possibility in the future perhaps of Kidney Vetch planting projects…don’t ask me how I would go about organising that…but if it seems viable then I don’t see why not. Attempting to extend the range of the butterfly would be quite an exciting project…rather than just outright introduction.

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SUMMING UP

I would like to thank again everyone who helped out surveying in the field, as well as those who provided inspiration and information. As a result we have here I hope an excellent picture of the status of the Small Blue Butterfly and its habitats up to 2012 in Berwickshire and North Northumberland.

The Small Blue was once present at Pease, St Abbs Head, Coldingham, Hawick and at a time frequent on the railway banks at Norham and Tillmouth.....this was once a widespread and common butterfly.

Small Blue Survey 2012 Iain Cowe 01890818314 orb@lammer.orangehome .co.uk