Butterfly Conservation Dorset Branch Newsletter No 82 Dorset Butterfly Report for 2015
www.dorsetbutterflies.com
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Counting butterflies Dorset Branch Who’s Who
President Website From Nigel Spring, Dorset Branch Chair Brian Dicker* Lyn Pullen* Wincanton. 01963 32453 Winfrith Newburgh. 01305 Welcome to our 2015 Butterfly Report. We hope you 853946 enjoy the new super-colour format! Butterflies are [email protected] [email protected] such stunning colourful creatures that it seems logical that our publications should be in full colour Chair & Reserves Manager Newsletter too. Many other branches have already gone over to Nigel Spring* Jane Smith* Sherborne. 01935 814029 this format and with the recent huge changes in print Sherborne. 01963 23559 or 07981 776767 [email protected] technology, the cost of colour is very little more than that of black and [email protected] white. We would welcome members’ comments on this.
Health & Safety As in previous years, the 2015 records show both gains and losses. Some Secretary, Garden Records & Keith Howland* of these are part of regular fluctuations but some of them are far more Wider Countryside Survey Pimperne. dramatic. It is wonderful to see how well the large gaudy species fared in Adrian Neil* [email protected] 2015 - species like the Brimstone and the Silver-washed and Dark Green Preston, Weymouth. Fritillaries. As in a Painted Lady year (we are still looking forward to the 01305 832937 Committee Member next one!), having large colourful butterflies easily visible in our [email protected] Richard Norman* Sturminster Newton. countryside is a very good way to generate interest among the public. 01258 472887 Treasurer [email protected] We can explain some of the fluctuations in numbers by linking them to the Georgie Laing* oscillations in the abundance of predators or parasitoids, as is the case Weymouth. 01305 766712 with Marsh Fritillaries, Holly Blues and others. Other ups and downs can [email protected] Meetings Arthur Bryant be matched to the variations in our unpredictable climate. We are very West Moors. 01202 892816 grateful to Judy Westgate for providing her meteorological data as usual, Membership & Branch [email protected] Liaison even if, sadly, the figures do not make for very happy reading! Several Mrs Robin George* months in 2015, important in the life-cycles of our more critical species, Conservation Gillingham. 01747 824215 Richard Belding were colder, wetter and had less sunshine than the 30 year average: not [email protected] good news. The drop in numbers of the Brown Argus may be due to the Dorchester. 01305 264868 [email protected] poor weather in early summer when the first brood females should have Records been laying eggs. Bill Shreeves* Shaftesbury. 01747 852587 Photo on back cover: Mullein Moth Much more worrying are the drastic changes that cannot be easily [email protected] caterpillar. Brian Arnold. explained. The continuing declines in Wood White and Small Pearl- bordered Fritillary do not seem to be explicable in terms of the lack of Butterfly Conservation. Company limited by guarantee, registered in England (2206468). suitable habitat. The Chalkhill Blue has crashed in numbers, particularly Registered Office: Manor Yard, East Lulworth, Wareham, Dorset BH20 5QP. away from the coast in Dorset (and indeed in Wiltshire). It could be that the same climatic changes which are favouring Adonis Blues and Silver- Charity registered in England and Wales (1254937) and in Scotland (SCO 39268)
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spotted Skippers are rendering the same downland 2010-14 Butterfly Records habitats less suitable for the Chalkhill Blues. And now it seems that the Small Copper has joined the list of species whose numbers are plummeting. The graph on page 10 shows that in three of the last four years of counts, the number of species showing declines exceeds the number showing gains. A very sobering picture! Small Copper. Charlie Steadman. Michael McCarthy in his book ‘The Moth Snowstorm’ refers to what he calls the ‘great thinning’, the loss of half the biodiversity of the UK in less than half a century, reflected in the reduction of moth numbers, the almost total disappearance of hayfields, the loss of swallows, martins and bats as a result of the crash in the abundance of dungflies and dung beetles since the introduction of avermectins for worming farm animals and horses, to name but a few. We are very fortunate to live in a very rural county, but much of Dorset is now effectively a wildlife desert, with fields of cereal, rape, maize for silage and intensive dairy pastures, all grown as monocultures with no room for wildflowers or the insects and other animals that rely on them. We are going to have to work very energetically both as individuals and through organisations like Butterfly Conservation to try to bring about changes in the management of the land around us which will lead to a reversal of these frightening trends. Finally, huge thanks to Bill Shreeves, Martin Raper and all their assistants who process the vast number of records that are sent in; also to Lyn Pullen for putting together this wonderfully comprehensive and attractive report; and last and most importantly, to all the ‘foot soldiers’ on the ground who devote hundreds of man-hours to recording butterflies: all your hard work enables us to produce this report and the records on which the future conservation of our butterflies can be based.
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Counting butterflies Butterfly Recording Cycle
ounting butterflies another likes to go out on ecords from Transect not yet very meaningful. We sounds very simple: go hunts for certain species. Walks and all the other have therefore included, C out and note down Secondly, how comparable are R schemes we have for overleaf, the map for the full how many you see. There are, all these figures from a multitude counting butterflies are pulled 2010-2014 recording period. however, two complicating of sources? There is no certain together every five years. As you can see, there are some aspects. answer, but, statistically, the We are part of the national “white holes”, where no Firstly, you need to encourage more records we get, the better organisation- Butterfly butterfly records were received, people to do the counting: the overall accuracy. However, Conservation- which undertakes and we are particularly keen that virtually all our records are from there is a method called transect this collation for the whole UK. these do not remain gaps in the unpaid volunteers. walking which calls for a certain next five years, so please visit place to be walked every week This means we record on a five- them if you can and send us the from April to September, under year cycle, and at the end of it, records. A few are inaccessible set rules, which gives us the best the slate is wiped clean and we for various reasons. data for comparing years. start collecting records all over Even how people like to send in again. We are now in the 2015- More detail can be seen on the their counts varies. Some like to 2019 cycle. website. type them into a computer, and We record butterflies in some prefer to stick to paper kilometre squares, and at the and leave the typing to someone end of each year we plot which Brimstone. Andrew Cooper else. butterflies have been seen in Then, what suits one person We have a number of counting which square, and to see where does not suit another: one needs scenarios and different ways to nothing has been recorded at all. to keep it simple and just jot send in the records, so there is As this report is about 2015 and down what they see while going something for everyone. You this was the start of the cycle, about their daily business, can see the full range in our the map showing where no another is housebound but can “Counting Dorset’s Butterflies” records have been reported is get out into their garden, and booklet, or on our website. Red Admirals. Lyn Pullen.
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Transect Walking 2015: The number of results
ransect walking The Wider Countryside Survey produces the most has its own importance, in that it T butterfly data, but there is a truly random survey (albeit are other sources, as shown in only done in July and August), the graph below. While transect whereas transect walks tend to results are scientifically good, be at butterfly hot-spots, and they are limited to certain there is probably a tendency for months, so our growing number these to also predominate on of records via the website, and the website. Please remember via national systems such as recording ‘ordinary’ butterflies is iRecord and Living Record are as important as noting the rare important for filling in the gaps. species.
Hod Hill. Carole Drake. Number of butterflies counted by type of Dorset maintains over 60 you can have a list of what record transect walks; given they are butterflies have been seen in walked 26 times a year, that’s which sections of the walk Migrant Watch 385 potentially over 1,560 actual previously, so you have a good Living Record 5,329 Wider Countryside 7,353 walks! You can understand, start to sort out what you are iRecord 15,654 therefore, that we need more seeing. Take your camera and Casual Electronic forms 19,749 volunteers to help with transect photograph any species of which Big Butterfly Count 28,387 walking. You only have to do as you are uncertain, so you can Website 33,714 many walks in a year as you feel ask for help later. Transect Walks online 135,853 you would like to. If you could help, please contact The above graph does not include the records we usually receive If you are worried about not Bill Shreeves (see contact details from the BTO (British Trust for Ornithology), the garden records being able to identify butterflies, inside back cover). or any records received on paper, which had not been added when it may reassure you to know that these results were compiled.
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2015: Weather Transect walk map 2015
hether butterflies average, compared to three in flourish or struggle 2014, being winter 14/15, March, W is dependant on a April, May, June, July and range of factors, one of which is September. Sunshine hours were the weather, so what was the below average for four months: weather like in 2015? March, May, July and August. As you can see from the graphs, How individual butterfly species the temperatures were low, react to weather is very with five months below the complex and under-studied, but average, compared to only one generally warmer, drier, sunny in 2014. These months fell in weather in spring/summer is May, June, July, August and good, as long as there is no September. Rainfall was also drought or heatwave. down: six periods below the
Mean average temperature - percentage 1.5 above/below 36 year average 1 1 1
0.5 0.2 0.2 0
-0.5 -0.4 -0.6 -1 -0.9 -0.9 -1.5 -1.3 Winter Feb March April May June July Aug Sep 2014/15
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Transect walk map 2015 2015: Weather
Rainfall in mm compared to 36 year average
60 43.7 40 20 7.8 0 -0.6 -20 -9.5 -15.1 -9.6 -21 -40 -41 -60 -53 Winter Feb March April May June July Aug Sep 2014/15
Sunshine hours compared with 20 year average 1.5 1 0.5 0 -0.5 -1 -1.5 -2 Winter Feb March April May June July Aug Sep 2014/15
Our thanks to Judy Westgate for supplying the weather data, which is based on a location in Fontmell Magna, North Dorset.
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2015 - How good a year? Transect Walking
he answer to the dropped out: Kingcombe Pound, ransect walks are very important in monitoring butterfly question “how good a Deadmoor Common, and populations, as they allow counts over a period of time to T butterfly year was it in Durlston Meadows. With an T be comparable by setting rules for how the walk is done and 2015?” is not clear: results were entirely voluntary workforce, it the conditions under which it is walked. The weather has to be very mixed. can be hard to keep a walk within set parameters, while the walker is limited to counting The number of times any specific going, though we try very hard butterflies 5m ahead and to 2.5m to each side - some people transect was not walked was to do so. We are always in need imagine themselves walking in a 5m square box. The route is set, greater than in 2014 and 2013: of more walkers, so contact Bill and divided into sections, linked to changes in habitat if relevant. Shreeves if you could help. only 22 out of 62 walks Walks are undertaken every week between the beginning of April produced results for all 26 The number of butterflies and the end of September, often by a team of people taking turns. weeks of the walking season. counted was the third best This may reflect the poorer since 2006, with the highest Overleaf you will find a map of the current transect walks. weather. number at one site being 62 sites were walked in 2015. 6,543 at Durlston East. Three walked the previous year
Total butterflies counted on all transect walks 160,000 140,000 120,000 100,000 80,000 60,000 40,000 20,000 - 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 Entrance to Melbury Downs. Lawrie de Whalley
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2015 - Unusual Sightings 2015 - How good a year?
he average butterfly count per site walked was good - sec- T ond only in the last ten years to 2006. Average butterfly count per transect walk site 2500 2094 2063 2060 2066 1869 2000 1746 1651 1561 1439 1503 1500
1000
500
0 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 he White Admiral 2010-14 preliminary map showed that the species no longer occurred in West Dorset, but in 2015, An interesting way of looking at The highest number of species besides unusual sightings in people’s gardens fairly close to a year is to calculate how many falling to zero was at Ferry Road T species on the combined walks (Studland), with eight. its known breeding areas in Sturminster Newton, Ferndown Forest did well by coming up from and West Brownsea, the arrows show highly unusual sightings to zero counts in the previous year the west of Lyme Regis on the Devon border and in North-west and how many did badly by Dorset very close to the Somerset border. This latter was coming down to zero. 2015 had photographed by Ian McNab in his DWT wildlife garden well clear equal numbers of species in of any woodland. each direction. The place with These sightings join the list in recent years of apparently impossible the highest number of species Chalkhill & Silver-studded Blues in the ‘wrong places’. up from zero was Ailwood (near Corfe Castle), with six. Silver-studded Blue. John Woodruff
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2015 - How good a year? 2015 - Garden Recording
measure of success or considerably from year to year. failure we use every The walk with the lowest A year is to look at where percentage of species below over half the transect walks have 2014 was Kinson Common, with a large number of species which 22%. The walk with the lowest increase or decrease compared percentage of species below to either or both of the totals their annual averages was Redhill for the previous year and the with 26%. annual average count for the species, which we term All the commentary on “winners” and “losers”. pages 11-21 is based on transect walk results. 2015 had far more down than up: 16 as opposed to five, but Essex Skipper. Mark Pike this statistic does vary e have over 100 people Adonis Blue, was not seen. W recording butterflies in Species which did better than in Balance of numbers of species more their gardens, with a fairly good than 2014 were the Brimstone, the spread across the County. Comma, the Painted Lady, the 50% above or below average 2015 was good in that two more Speckled Wood, and the Ringlet. 30 species were reported in The Silver-washed Fritillary was gardens than the previous year, 20 seen in 26% of gardens (it with a total of 35. reached 34% in 2013). 10 In terms of actual species, three Three species did badly: the turned up which were not seen Clouded Yellow, the Common 0 in 2014: the Essex Skipper, the 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 Blue and the Small Copper. Purple and White-letter Over 50% up Over 50% down Hairstreaks, while one, the
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2015 - Wider Countryside 2015 - Winners
he Wider in 2013 and a low of 29 in 2011. BUTTERFLY OF THE YEAR: BRIMSTONE Countryside The top species was the The Brimstone had a record count of 3,567 if you recording scheme Meadow Brown which was seen T add the totals on all the transect walks together. aims to find out how butterflies in 97% of the places surveyed, Cashmoor (near Blandford) achieved the highest are doing in ordinary places, with a total count of 2,140. The total of 520. rather than in “butterfly total numbers counted each year Photo: Nigel Tooth hotspots”, so the places can be seen in the graph below. searched are selected at Species not reported in 2015 ive species had gains of rimstone random, though there is a set that had been seen before were more than 50% on both method of searching. In Dorset, The success of this the Small Blue and Green 2014 and their annual we have one of the highest F B species might be due to Hairstreak, while those gained averages. gains for the caterpillar and number of squares to cover, so were the Chalkhill Blue and 1. Brimstone. chrysalis stage in summer help is always needed: contact Purple Hairstreak. The Painted 2. White-letter Hairstreak (highly unlikely), the warm wet Adrian Neil. Lady did better than it has in the 3. Purple Hairstreak winter of 2014/15 (doubtful) or 2015 saw 34 species recorded, last few years, while the Large 4. Silver-washed Fritillary the extended flying period which compared to a high of 37 Skipper did badly. 5. Dark Green Fritillary made possible by the warm, dry WCS Number of butterflies counted It is interesting that four of the and sunny April (very likely). 9000 8134 five species which gained on Brimstones always seem to do 8000 7522 7353 their annual averages were better in the spring, when they 7000 single-brooded species. The emerge from hibernation, 6000 Brimstone is also single- rather than in the late summer, 5000 4481 4056 brooded, but is different in that 4000 3385 when the new generation are 3000 the adult butterfly hibernates feeding up to survive the 2000 through the winter. winter: Cashmoor had 337 in 1000 The Fritillaries overwinter as spring and 183 in summer; 0 Badbury Rings 151/95 and 2010 2011 2012 2013 2014 2015 caterpillars, Hairstreaks as eggs. Moors Valley 213/41.
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2015 - Winners 2015 - Rare Migrants
hite-letter Other sites where we know of In 2014 a number were seen at Hairstreak it include Bindon Hill St Alban’s Head near Swanage, W This butterfly is (Lulworth), Harman’s Cross and so there was hope of a breeding only recorded on one transect Wareham Common, plus a new colony, but none were seen in walk in Dorset: our Butterfly site discovered at Puddletown. the area in 2015. Reserve at Alner’s Gorse. This butterfly uses elm on which Only one was seen anywhere in Here it was 100% up on both to breed and was very hard hit Dorset in 2015, in Poole, which 2014 and its annual average. A by Dutch elm disease. In the is likely to have been a release. Long-tailed Blue. Photographed by lot of conservation work has records for 2010-14 it is only Monarchs were seen in early Cath Walker in Dorset in 2013. been carried out at this recorded in 17 kilometre August and late September, but squares and is declining, though 60 counted and eggs being location, so hopefully we are so many of this species are found. There were three getting it right. it is probably seriously under- captive bred these days that it is recorded. sightings in Dorset, on 29 impossible to tell if any are August, 5 September and 20 genuine migrants. A sighting on Look for the White-letter Hairstreak in 2017. September, but only of the adult 1 August was too early for it to stage. Although the species prefers wych elm, they will use English or have been a migrant, but there smooth elm. Watch the tops of them in the last week of June and were hopes for a sighting of It is worth looking out for it if the first week of July (at this time the Purple Hairstreak should not more than one just over the you buy mange-tout peas, as the be out, so you cannot confuse them). The males fly around in the border at Stourhead in non-adult form is sometimes tops of trees, so may be around Wiltshire. However, extensive accidentally imported in them the elm or nearby. In July you enquiries eventually uncovered and may survive to become an may find the butterflies lower a butterfly wedding had taken adult if you look after it. down, nectaring on flowers. place at the Apollo Temple. If you want to identify the adult, See our website for a list of Long-tailed Blues arrived in just look for the small tails at places they have been previously some numbers in the south-east the end of the hindwings. recorded: of the UK in 2015, with at least www.dorsetbutterflies.com. White-letter Hairstreak. Mark Pike
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2015 - Rare Migrants 2015 - Winners
he Map is an intriguing urple Hairstreak butterfly, common in This is found on five of central and eastern T P our Transect Walks, 60% Europe and expanding in of which increased by over 50% western Europe. It has two on 2014. broods in a year, and they look very different: the spring brood The top sites were Alners Gorse, Map summer brood. Brian Arnold could be mistaken for a White where 19 were counted, Moors Admiral, while the summer ones visits in 2015 only found three Valley with 11 and Lydlinch with Purple Hairstreak. Tim Melling. are more Fritillary-like. spring individuals and none eight. In the 2010-2014 period, A release of these butterflies, thereafter. they show as declining, but they are probably the most badly described by the person Swallowtails were less recorded butterfly in Dorset. involved as accidental, took common. The UK version of this Like the White-letter Hairsteak, Purple Hairstreaks very place near Swanage in 2014, and gorgeous butterfly is now inconsiderately spend most of their time in trees. If you are able to the adults were seen to lay eggs, restricted to the Norfolk access the Internet, there is an interesting article by D E Newland: so hopes were high that they Broads, but there is a European “Behaviour of Purple Hairstreak butterflies in the canopy of oak might establish, as our climate is race which visits from time to trees at Sheringham Park, Norfolk”. He was able to watch these suitable for them. However, time. butterflies from a platform which looked down on the tree tops, and concluded that they favoured dips in the canopy, presumably because of the shelter afforded.
Look for Purple Hairstreaks. The butterflies are known to be fairly sedentary during the day, and Mr Newland recorded peak activity as late as 7.00pm, so get those binoculars out and go for an evening stroll to your local oak One of the 2014 Swallowtails, missing Map spring brood. Neil Hulme. trees! They are on the wing in July and August. its red hind spots. Tim Field.
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2015 - Winners 2015 - Regular Migrants
ark Green Fritillary The third of the regular migrants The website, recording all year There are 26 walk is the Red Admiral: once only round, picked up Red Admirals D sites recording this a migrant, but now over- in every month of 2015, butterfly, and 69% of them had wintering in this country. suggesting they are becoming gains of more than 50% on Transect walks counted 884, but better established as a locally annual averages. The best site the time period for walking is breeding species: was Melbury Down, with a Dark Green Fritillary. Peter Lister. limited to April to September. count of 122. January - 2 February - 10 1000 Dark Green Fritillary count March - 13 on all Dorset transect walks October - 56 November - 14 500 December - 5 Red Admiral taken in November 2006. Lyn Pullen 0
Red Admiral total counted on
2002 2009 1996 1997 1998 1999 2000 2001 2003 2004 2005 2006 2007 2008 2010 2011 2012 2013 2014 2015 1995 all transect walks
ilver-washed Fritillary 8,000 6,691 59% of sites gained over 7,000 6,000
S 50% on annual averages, 5,000 4,062 though the species dropped in 4,000
the total walks count compared 3,000
1,835
1,817
1,747
1,685
1,562 1,562
1,545
1,381 1,319
2,000 1,105
1,086
986 986
976 976
906 906 884 884
to the last two years. 745 610 610 1,000 453 Top site was Lydlinch with 160. -
Six Valezina form were identified.
1998 2006 2009 1997 1999 2000 2001 2002 2003 2004 2005 2007 2008 2010 2011 2012 2013 2014 2015 SWF Valezina. Chris Rowland. 1996
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2015 - Regular Migrants 2015 - Losers
ome butterflies are not 3,123, and 2009 reached 5,035, species suffered We will look at some of these in able to breed in this but 2015 only managed 321. This above 50% losses on more detail. S country because it is too was despite large numbers of 16 either 2014, or their cold, but regularly visit us as them moving through southern annual average - or both. This migrants. There are also a few Europe, which we had hoped compares to 12 losers in 2014 odd migrants each year; if these would reach us, but did not. and 14 in 2013. are genuine chance arrivals, they The Clouded Yellow is 1. Brown Argus (both) have probably made it to us another very variable regular, 2. Small Copper (both) because of winds and other which occasionally breeds here 3. Duke of Burgundy (On av) chance factors. It can be difficult in the summer, and has been 4. Silver-spotted Skipper (On to tell genuine migrants from known to overwinter on the av) releases. Some releases are Bournemouth Undercliff. 90 5. Chalkhill Blue (On Av) deliberate (though usually were seen in 2015 - down from 6. Wood White (On Av) Brown Argus. Chris Becker. unsuccessful) but there is also an 284 the previous year. increasing use of butterflies at 7. Small Pearl-bordered rown Argus Fritillary (On Av) weddings and other events. This collapsed on a 8. Painted Lady (On Av) The following descriptions B majority of its 30 sites: 9. Adonis Blue (On Av) continue to focus on numbers by 67% on 2014 and 80% on its 10. Green Hairsteak (On Av) counted on transect walks. annual averages. 11. Wall (On Av) This was probably brought about The Painted Lady is a regular 12. Small White (On Av) by the very poor egg-laying migrant. There is the occasional 13. Grizzled Skipper (On Av) weather of early summer, which year when huge numbers arrive, 14. Small Tortoiseshell (On left the second broods top of which was 1996, when we 2014) struggling. recorded 18,311 - a wonderful This picture from 2014 was taken by 15. Clouded Yellow (On 2014) The top count was at Ballard time when fields with thistles or Nick Urch at Langton Herring, when a 16. Green-veined White. (On Down, with 186. other nectar plants were alive large brood emerged: this is a female 2014) with fluttering wings. 2003 saw coming out of its chrysalis.
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2015 - Losers 2015 - around Dorset
The Small Copper was the Coppers have the third brood orth Dorset had four east. We are particularly other species which declined and there are no transect walks winners: interested to see if the species against both the previous year in October to measure this. N can survive right along the ridge, and its annual average. It Volunteers were asked to as measured by the chain of nine declined by over 50% on its 52 extend the walking season last Dark Green Fritillary, up on walks* along it. sites; 52% of its sites were below year but few attempted this in 78% of sites. Small Heath doing well. 2014 and 79% below annual Dorset. Small Blue, up on 75% of sites. averages. Top count was 50 at Adonis Blue some decline but Brimstone, up on 67% of sites. Lorton Meadows. This brought The Duke of Burgundy has still all along the ridge. been a loser for the last three Marbled White, up on 57% of Wall still present throughout. years. It is now only found on sites. Dingy Skipper down and two the walks at Wimborne St Giles There were two losers in this gaps in the chain. and Cerne, where it has seen a area: spectacular revival - hopefully at Lulworth Skipper counts up Small Copper, 58% down least partly due to all the but gaps for fifth year in a row. on 2014 and 100% down conservation work being carried on annual average. Chalkhill Blue - a species of Small Copper. John Van Crugten out there for it. They have been great concern - has been lost on lost on the North Dorset sites Brown Argus, 67% and all sites except Bindon Hill. to an end its recovery between where they used to be. 89%. Graying has collapsed at 2012 and 2014 Measured by how many Bindon; only survives at Ballard. The collapse was also probably a kilometre squares in which they outh Dorset has some result of poor summer weather have been recorded, which takes Small Blue only at Bindon. different transect walks, on egg laying and caterpillar in data beyond just transects, not walked every week, *Nine walks are Bindon, Grange survival. Some experts think that there has been a loss of 36% S aimed at measuring the species Arch, Ridgway Hill, Knowle Hill declines in the Wall might be between the recording periods seen on the Purbeck Ridge, 1 and 2, Corfe West Hill, Corfe attributed to failed third broods of 1995-9 and 2010-14. which goes from Bindon in the Mound, Ailwood Down, Nine in October. Like the Wall, Small The good news is that a west to Ballard Down in the Barrow Down & Ballard Down.
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2015 - Around Dorset 2015 - Losers Hambledon, which failed. ast Dorset had three est Dorset had
winners: no outright On the transect route at winners, but four E W Fontmell, it had its first ever zero species did manage to come in since recording started in 1980. Ringlet, up on 67% of its nine above their annual averages on It is not extinct but no longer sites. over half their sites. appears on the walk route. This Silver-washed Fritillary, up on Silver-washed Fritillary up on is worrying, because it shows 60% of its five sites. 89% of sites. that the bare short swards and Peacock, up 57% on 14 sites. Dark Green Fritillary up on 75%. Duke of Burgundy. Adrian Reid. rich nectar areas which it likes landscape-wide survival plan has are probably shrinking. It is also Chalkhill Blue up on 67%. been instigated by Butterfly infuriating that, though the Brimstone up on 64%. Conservation HQ for West management in the past has tried That was balanced by four losers Dorset. Dukes have also been to follow all the research (percentages refer to 2014 and seen at Brandis Down (opposite suggestions, the colony has never annual average respectively): Fontmell) for the first time since expanded as is happening in the the 1990s, in the same place as south east. Possibly their climate Brown Argus 89% & 89%. they were then. has been getting warmer and Adonis Blue 83% & 83% drier than in the west.
Small Copper 60% & 73% ilver Spotted Skipper has remained confined to Common Blue. Penny Hawes. Green-veined White 75%, 56%. S Fontmell Down except for The spectacular loser was the a colony on Martin Down (really Common Blue, with over half of in Hants), plus about three sites showing more than a 50% records of ones that strayed on decline on both 2014 and annual to Clubmen’s Down, Compton averages. Down and Melbury Beacon plus Green-veined White. Sarah Faulkner. an introduced colony on Silver-spotted Skipper. Ken Dolbear.
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2015 - Losers 2015 - Losers
halkhill Blue has had The examples in the graph he worst stories belong Small Pearl-bordered four years as a loser below show the importance of to the Wood White and Fritillary C with 92% of its 12 sites counted data on the walks. It T the Small Pearl-bordered Another butterfly sadly lost from over 50% below annual average. shows that less Chalkhill Blues Fritillary. our walks. From 1990-1997 It has experienced a collapse on were counted at all walk sites in The Wood White is no longer there were still good counts on its North Dorset walk sites 2015 than were counted in one seen on any of our walks, whilst walks at Powerstock, Kingcombe, (from before 2000), and the week at Fontmell Down in 1996. in past years the numbers Bracketts, Deadmoor & Lydlinch. total extinction of West Dorset The decline has been in the counted reached 84 (2000) and By 2004 none were being sites like Cerne, Southfield and central and southern Chalk, an even better 92 in 2005. counted. There was a brief Lankham bottom, so that while the colonies on Portland revival from 2005 with new Portland remains the only remain strong. The reasons for walks at Stonebarrow & Bindon healthy stronghold. Bindon Hill this collapse are not obvious and Hill, but by 2013 these sites had remains the only flourishing need research urgently. also collapsed. Purbeck site. Elsewhere the only surviving colony is between Studland Golf Wood White. Mark Pike. Chalkhill Blue Comparative Counts Course and Agglestone. The 5000 We feared the photo above, colony is spread quite widely and (not on a walk) would be the there is hope that a new 4000 last seen in Dorset. However, we National Trust management plan 3000 discovered late in the year that might keep the colony going. 2000 two had been seen at the start There is an outside chance that of the coastal walk from Lyme it may still survive on the Army 1000 Regis via Ware Cliffs. Further Ranges or the private area of 0 visits to this area would be good Bindon Down but special 1996 Dorset 1996 count on 1996 count on 2015 Dorset if they can be done safely. - there permits are required to visit. Count for 12 Fontmell Fontmell for just count for 11 have been a lot of landslips. sites week 19 sites
18 19