`Frits About` 2015 No 1 - Butterfly Conservation

To retain and respect confidentiality of precise sites and often extremely sensitive goodwill towards conservation efforts, some site descriptions are such as only to be recognisable to those already aware of
each site’s location. Sites only have public access to extent shown on OS maps.
“FRITS ABOUT, 2015 – No. 1”
(24 new reports in this edition)
Dear All
Apologies that due to technical problems with e-mail delivery, many of you would not have received the later editions of Frits About, 2014. Working
with BC Wales office, we’ve come up with a new web-based e-News for 2015 which includes Frits About. Judy in the Wales office will be pleased to
receive feedback on the E-news generally, but please keep Frits About contributions coming to me but at my new e-mail address of
rgsoverton@gmail.com. (If anyone particularly wants a copy of any 2014 Frits About, then if you let me know by e-mail, I can send you the relevant copy).
Judy adds that you will also find links to the 2014 and 2015 editions on the BC Wales website page.
With one of the driest, sunniest winters in recent years (at least in South Wales), we’ve been able to achieve even more management than usual on
sites. As the good weather continued right up to the end of April, we’ve received a good number of reports of Marsh Fritillary larvae, violet-feeding
fritillary habitat looking resplendent with good (if late) violet inflorescence, but sadly also of a few late grass fires. Fortunately, many of the
important Marsh Fritillary (MF) areas got off lightly so far, e.g. Tonyrefail, Mynydd Mawr and Seven Sisters. Others have suffered like Ystrad Fawr
in Ystradgynlais and Mynydd Ruthin in Vale. The issue has however received a lot of media attention and NRW have been co-ordinating many of the
positive preventative actions, concepts and local initiatives. Most partners in the working group around SE Wales have been keen to promote positive
benefits of seasonal grazing as a means of reducing fuel loads and benefitting biodiversity, our fritillaries in particular.
Summer 2014, like 2013, contrasted strongly with the dire summer of 2012. 2014 seems mostly to have been very good news. Many smaller Marsh
Fritillary sites or indeed metapopulations have had long awaited increases e.g. Seven Sisters and Rhos Tonyrefail, whereas others have shown even
further strength than previously - like Gower Commons, Heads of Valleys, Mynydd Mawr, Ystradgynlais, Castlemartin, Puncheston and Blaencleddau.
In North Wales, despite record webs at Harlech, there seem to have been too many uncertainties about ensuring the right management to be
confident of the longer term of the NW part of its Wales distribution. Hopefully, we’ll be proved wrong here! High Brown Fritillaries (HBFs) had
another great year in the Vale of Glamorgan. Plans are afoot to try to expand habitat still further, and rise to the challenge of increasing
management and even new sites, in a changing and challenging funding climate.
As always, contributions to Frits About are very welcome – but don’t forget to send in your records to county recorders as well. There is now also a
Facebook discussion group set up & run by Mike Bright of BC’s South Wales branch <https://www.facebook.com/groups/ButterflyConservationSouthWalesBranch/>
Reminder: reports to Frits About are no substitute for actual records. However, county recorders
are included in Frits About circulation list and will thus be alerted to look out for
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actual records in due course. Please therefore follow up in usual way.
To retain and respect confidentiality of precise sites and often extremely sensitive goodwill towards conservation efforts, some site descriptions are such as only to be recognisable to those already aware of
each site’s location. Sites only have public access to extent shown on OS maps.
1. Pearl-bordered Fritillary (6) reports
Ceredigion.
20th April. Maggie Sproule writes……”Have just spent a lovely sunny afternoon at Cwm Soden. Plenty on the wing. Squadrons of Peacocks, 2 Commas, 2 Small
Tortoiseshells, at least 15 Speckled Woods, a few Orange Tips, Several Small Whites, 1 Small Copper, 6 Holly Blues.....all newly emerged males and YES, 2 Pearl
Bordered Fritillaries.
“Jasonbirder” also reported “A few Pearl-Bordered Fritillary on the wing at Cwm Soden this morning. Nice to see the National Trust Managing the habitat carefully
for them. Belated pics of Pearl-bordered Fritillaries at Cwm Soden (Pembrokeshire) from Bank-holiday Monday” – UK Butterflies.
Montgomeryshire
27th April. Simon Spencer did a PBF timed count today at Llanymynech Rocks MWT reserve enclosure: 10 PBF in 22 minutes sunshine between 2.00PM and 2.40PM
= 27 per hour which is presumably a pass. 12°C; 50% blue sky and wind 3 W. Clouded over.
(Almost)
Monmouthshire (1.5kms into Herefordshire but close enough!)
27th April. Bill Jones “managed to see 8 or 9 Pearl-bordered Frits and managed a bonus Grizzled Skipper as well ...what a difference (from same time last year).
The usual 'hot-spot' was rather quiet, I only saw two P-b F's there, I was surprised at the shortage of Bugle this year too, it's a favoured plant of the species and I
will check on my next visit to see if there is any improvement, it could still be a bit early, I'm pretty sure both numbers of P-b F and bugle will improve over the
coming weeks...at least I certainly hope so” – UK Butterflies.
George Tordoff and Gareth Tonks were both (independently) at Ewyas Harold Common on 4th May (partly at same time) and each saw 4 PBFs, mostly fresh males.
(David Moore was also there on the same day and also reported PBF - Grizzled Skipper).
2. Small Pearl-bordered Fritillary (0) reports
No reports so far, but expected first half of May onwards. Out in Devon 30 April. Cwm Soden can’t be far behind?
Reminder: reports to Frits About are no substitute for actual records. However, county recorders
are included in Frits About circulation list and will thus be alerted to look out for
2
actual records in due course. Please therefore follow up in usual way.
To retain and respect confidentiality of precise sites and often extremely sensitive goodwill towards conservation efforts, some site descriptions are such as only to be recognisable to those already aware of
each site’s location. Sites only have public access to extent shown on OS maps.
3. Marsh Fritillary - (13) reports
Summary of 2015 larval activity reports
Date
25th Feb
4th March
25th March
1st April
2nd April
6th April
10th April
15th April
16th April
16th April
22nd April
28th April
4th May
8th May
Site
Rhos Llawrcwrt
Rhos Llawrcwrt
Aberbargoed Grasslands,
Puncheston
Cae Lindon, Ystradgynlais
Welsh Moor
Cerrig y Gwaenydd, nr Harlech
Median Farm, Cross Hands
Tumble, Mynydd Mawr
Puncheston
Tonyrefail
Seven Sisters, Neath Port Talbot
Puncheston
Ystradgynlais
County
Ceredigion
Ceredigion
Caerphilly
Pembs
Brecknock
Glamorgan
Merioneth
Carms
Carms
Pembs
Glamorgan
Glamorgan
Pembs
Powys
Reported by
Ruth Harding
Ruth Harding
Karen Wilkinson
Steve Coker
Steph Coates
Deborah Sazer
Helen Bantock
George Tordoff
Isabel Macho
David Redhead
Lucie Bromfield
Richard Smith
David Redhead
BC & NRW on site
Description
Two small groups near rampart to the pingo.
Two groups.
Caterpillars noticed in 3 fields.
c. 70 larvae – aggregations in the sun, despite strong cool winds
Small bunch basking.
2 small groups seen along northern edge
Up to 200 seen. + 5 webs with parasitized tiny (0.5cms) larvae
5 larvae seen – all solo and still fairly small
Several larvae seen - all 1.5 to 2cms.
10 larvae – 1 to 2 cms – in 40mins.
One larva basking – known site – not burned this year – yet!
Probably 20 or more larvae on shortish sward areas of NRW land.
74 larvae in 40mins.
At least 20 larvae, fully mature and one in process of pupating.
No reports of adults yet in Wales, but seen on 3rd May in Wiltshire.
Reminder: reports to Frits About are no substitute for actual records. However, county recorders
are included in Frits About circulation list and will thus be alerted to look out for
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actual records in due course. Please therefore follow up in usual way.
To retain and respect confidentiality of precise sites and often extremely sensitive goodwill towards conservation efforts, some site descriptions are such as only to be recognisable to those already aware of
each site’s location. Sites only have public access to extent shown on OS maps.
4. Dark Green fritillary (0 reports)
5. High Brown fritillary (1 new report)
Spring season had been running late until mid-April, after which things caught up. Just one HBF larvae has been found so far, but health issues have prevented our
two most eagle-eyed searchers from getting out on site. We do however have an MSc student project about to start monitoring larval activity against ambient
temperature and habitat micro-conditions.
Vale of Glamorgan
The graph below shows the latest overall index for HBF, at (still) it’s only known Welsh site.
Old Castle Down and Alun Valley High Brown Transects 1995-2014
25
Index (Adults per hour)
20
15
10
5
2014
2013
2012
2011
2010
2009
2008
2007
2006
2005
2004
2003
2002
2001
2000
1999
1998
1997
1996
1995
0
Year
Reminder: reports to Frits About are no substitute for actual records. However, county recorders
are included in Frits About circulation list and will thus be alerted to look out for
4
actual records in due course. Please therefore follow up in usual way.
To retain and respect confidentiality of precise sites and often extremely sensitive goodwill towards conservation efforts, some site descriptions are such as only to be recognisable to those already aware of
each site’s location. Sites only have public access to extent shown on OS maps.
We completed the violet and habitat monitoring transects in May/early June 2014 and just recently wrote it up, a summary follows.
Trends
 The current 26 sub-sites amount to 73.8 hectares and are spread across 254 hectares of unimproved potential habitat, which constitutes the current
extent of the site.
 From 2002 to 2006 the violet percentage cover doubled to 6%, bracken litter increased slightly, grass reduced slightly and sward height reduced by two
thirds. These positive habitat changes were reflected approximately by an increase in High Brown Fritillary adult sightings per hour of three to fourfold
between summer 2002 and summer 2006.
 From 2006 to 2010 the violet percentage cover dropped back to just under 4%, bracken litter again increased slightly, grass reduced slightly but sward
height increased slightly. These less positive habitat changes in violet density and sward height were probably due in large part to a series of wetter
summers without increasing grazing, but overall High Brown Fritillary adult sightings per hour stayed around 2006 levels during this period to summer 2009.
 2010 results showed some differences between the sheep-grazed “common” (supplemented by our small-scale patch mechanical management) and the
entirely mechanically managed private land, east of the river. In particular, violet density in latter at 4.75% was more than double the 2% across the
common. The emphasis in commoners’ management during this period had been regular mowing of firebreaks, a very small percentage of the common, rather
than the required rotational patch management across the main common, given that grazing levels were having little effect on scrub and bracken height.
 2014 overall results show a slight improvement in violet density, but reduced bracken litter and increased grass cover, which would favour some violetfeeding fritillaries but less so the High Brown.
 Looking at differences between common and un-grazed private land to east of river is again somewhat revealing. Whilst violet density is again (slightly)
better east of river, the difference in bracken litter content and grass cover is significant, with “common” significantly less litter but much more grass
component. In fact, in 4 years, “common” samples show a doubling of grass cover from 20% to 40%. On the other hand, management by commoners has
started to change on Old Castle Down with a dense patch cut two winters ago showing positively in both habitat data for sub-site 24S (just one of 11 common
sub-sites) and as a likely component in the record breaking 2013 adult sightings numbers.
Our thanks go to all volunteers who helped with habitat sampling, including Hugh Lansdown, Mike & Rudi Bright, Paul Gadsby, Chris Lewis and Gareth Tonks. The late
Belinda Ashong also helped during the last few days of her working life and just weeks before she passed on.
We are currently undertaking habitat sampling of those sub-sites positively managed in winter of 2014/15 either by BC volunteers (coppicing), Heritage Coast staff
(using power scythes) and commoners (using agricultural machinery). This should help to inform management practice for future years and other sites.
This newsletter was compiled from reports received up to midday on Monday 11th May, but do keep reports coming in and I’ll pass on to
BCW as soon as enough received or to suit their dates. Many thanks to all contributors and apologies, if I’ve missed any out!
Richard Smith, 11th May 2015
Reminder: reports to Frits About are no substitute for actual records. However, county recorders
are included in Frits About circulation list and will thus be alerted to look out for
5
actual records in due course. Please therefore follow up in usual way.