Glasgow & SW Scotland Butterflies

Glasgow & SW Scotland Branch Website

July 21, 2010

Commas confirmed breeding in South West Scotland

Filed under: Butterflies — Tags: , , , , , , — Scott Shanks @ 1:11 am

In recent years we’ve seen a significant increase in the number of Comma sightings in SW Scotland. Until now these records have all been of adult commas, but thanks to Heather Young of the SW Scotland branch we now have proof of Commas breeding in the branch area.

Comma Caterpillar 13-07-2010

Comma Caterpillar 13-07-2010

On the 13th of July, Heather found this nearly full grown caterpillar on an elm near Bridge of Allan, Stirlingshire (NS788988). She suspects it was wych elm, but is having the elm species confirmed by a botanist to be sure. The caterpillar began to pupate a few days later.

There have been only 2 other records of comma caterpillars in Scotland in recent times. On both occasions they were in the Borders. The first was seen in 2006 at Sprouston near Kelso, on elm, and the second at Duns in early July 2010, on nettle.

The Comma caterpillar is quite distinctive, with a large white patch at the rear of the body which gives them the appearance of a bird’s dropping. The mature caterpillar will sit happily on the upper surface of leaves, trusting in their bird-dropping mimicry to keep them safe from predators. In England and Wales comma caterpillars can be found on stinging nettles, elm, wych elm, hops and occasionally currents. The pupa resembles a dried leaf dangling from the food plant and is much harder to find!

If you are out for a walk and pass patches of nettles or a stand of elms in SW Scotland keep an eye out for Comma caterpillars (and adults!) and let us know.

Heather Young & Scott Shanks

Caterpillar photograph (c) Heather Young 2010.

January 21, 2010

Ayrshire Small Blue Reintroduction Project

 

Pair of Small Blues mating on Kidney Vetch

Pair of Small Blues mating on Kidney Vetch

The Small Blue (Cupido minimus) is the UK’s smallest butterfly (wingspan 16-27 mm). Colonies of this charming little butterfly can be found from the north of Scotland down to the south of England, but became extinct in south west Scotland in the early 1980s. In 2007 it was added to the UK Biological Action Plan (BAP) species list after suffering a significant decline in distribution.

 

 

The butterfly’s small size and weak flight mean that the adults are quite sedentary, with few individuals moving further than 50 m from the colony during their short lives. Both sexes are similar with dark slate blue upper wings and silvery blue undersides with a few dark spots. Males often have a dusting of blue scales on the upper-wings, while the females tend to be slightly browner than the males. In Scotland, adults can be on the wing from late May/early June through to July, depending on weather conditions. A small second brood may be seen in August/September in exceptional years.

The female lays a single egg on the flower heads of kidney vetch, the caterpillar food plant. Only one egg tends to be laid per plant as the young caterpillars can be cannibalistic. When not being anti-social the caterpillar feeds on developing seeds in the flower head, undergoing 3 moults before hibernating under moss or in a crevice in the soil. The following spring the caterpillar pupates without further feeding.  Adults seem to prefer nectaring on the yellow flowers of kidney vetch or birds-foot trefoil, although other plants may be used.

Kidney Vetch flower colour forms

Kidney Vetch flower colour forms

 

 

 Colonies of this butterfly tend to be small and are prone to local extinctions due to their dependence on the levels of kidney vetch flowering in the colony area. Habitat fragmentation and loss due to building developments, changes in grazing and scrub encroachment, can all quickly make sites unsuitable for this habitat specialist species. Most colonies are found at coastal locations where erosion exposes bare ground where new kidney vetch seedlings can germinate and the adults can bask in the sun. Colonies may also be found at old industrial brown field sites or quarries; again with lots of bare ground and low fertility where the kidney vetch does not get out-competed by grasses. Low levels of grazing by rabbits can help maintain small blue colonies; however they do tend to eat the flower heads, as do sheep. Autumn /winter grazing and ground disturbance by cattle or horses is ideal at managed sites.

 

Working with the Scottish Wildlife Trust we would like to reintroduce this charming little butterfly to south west Scotland. Gailes Marsh is an SWT nature reserve situated just south of Irvine on the Ayrshire coast, and just 1km from the site of Ayrshire’s last small blue record.

Map of Gailes Marsh reserve

Map of Gailes Marsh reserve

The reserve currently boasts a range of butterfly and moth species including common blues, small coppers and dark green fritillaries. An area with a high density of kidney vetch exists in the south west of the reserve. We plan to expand this area and also transform the north- west section of the reserve into good small blue habitat. Coastal dunes west of the reserve contain suitable small blue habitat with good amounts of kidney vetch.

It is hoped that we will eventually see natural colonisation of this area by butterflies from the reserve.

 

The timing of the actual reintroduction will depend on how long it takes to create good quality habitat and maintain the levels of kidney vetch flowering on the reserve, which must be sufficiently high to support a healthy butterfly population. Kidney vetch is a short lived perennial which can take between 2-5 years to flower depending on conditions. We are currently in discussion with other branches of Butterfly Conservation about the source of initial small blue stock for the project.

 

Habitat creation at Gailes Marsh is due to commence in early 2010. The fertile top soil will be removed to create strips of bare sandy subsoil and south-facing soil banks that will be sown with kidney vetch seed. The areas sown with kidney vetch will be sheltered from the wind by planting native hedging along the western edge of the reserve.

Small Blue Buttefly on Kidney Vetch

Small Blue Buttefly on Kidney Vetch

 

Anyone who would like to help with this project would be very welcome indeed. We are currently looking for volunteers to help plant the hedges and sow kidney vetch. If you are able to find space in your back garden, window sill or green house to grow kidney vetch plants for the project, we can provide you with seed.

 

In the next few years we will also need volunteers to help monitor kidney vetch germination and flowering at Gailes Marsh and areas outside the reserve. After the small blues are introduced to the reserve we will need volunteers to help with timed counts of adult butterflies during their short flight season. This is necessary to monitor how well the project is going. Training in using a GPS device to accurately monitor kidney vetch patches or butterflies can be provided to any interested volunteers. This is a fantastic opportunity to get involved with real conservation work for a native Scottish species.

 

Scott Shanks

(scottshanks01@msn.com)

 

 

 

January 16, 2010

New edition of ‘On the Spot’ out now!

The new 25th anniversary edition of On the Spot, the newsletter of the Glasgow & South West Scotland branch of Butterfly Conservation is out now!

On the Spot January 2010

On the Spot January 2010

Glasgow & SW Scotland branch members should get their copy in the next day or so, in time for the 25th anniversary of the founding of the branch on the 19th of January!

Scott Shanks (Newsletter Editor)

April 27, 2009

Butterfly Walk, Little Drum Wood

Filed under: Events — Tags: , , — Heather Young @ 4:24 pm

Sunday May 24th. 2pm., Little Drum Wood, Brig o’ Turk.  

  

Meet in the Car Park at NN548063, on the south side of the A821 opposite Lendrick Lodge, just east of Brig o’ Turk. For a map of the location click here 

Little Drum Wood is part of the Woodland Trust’s Glen Finglas Estate, and borders the north shore of Loch Venacher. There are several waymarked routes throughout Glen Finglas ranging from ½ an hour to 7 hours duration, but we will be exploring suitable butterfly habitat within, and around the periphery, of the wood itself, at a leisurely pace, so the walk will be suitable for anyone used to a little bit of physical exercise. The event is being organised as part of Scottish Biodiversity Week, and amongst other things there is a photographic competition with the theme ‘Colours of Nature’, so don’t forget your camera (for more information click here).

Butterflies are obviously the primary targets, but if the weather refuses to co-operate, there will be lots of other interesting things to look for instead. Little Drum Wood is ancient woodland, well known for its carpets of bluebells and rich birdlife (including both pied and spotted flycatchers).

Bluebells © Ramsay Young

The butterflies we are particularly hoping to see are Green Hairstreak; tiny, feisty little creatures that glitter like jewels as they tilt their wings to catch the sunlight, as they (the males) hold territories amongst the bilberry and heather at the edge of the wood.

 
Green hairstreak © Maurice Young

Green hairstreak © Maurice Young

 
On the wing from the end of April and continuing well into June, we should be sure to find them if the sun is shining! See the ‘species’ pages for further information on their ecology. We will also be searching suitable habitat for the Pearl-bordered Fritillary, the subject of a co-ordinated survey effort in 2009 – if you would like to get involved please see our ‘surveys’ page for details. On the wing from the beginning of May, if they are present in the woodland clearings we should be able to find them, but need to be careful about identification, as they are easily confused with the Small Pearl-bordered Fritillary, which emerges a little later, but could well be around by the 24th. May.

 

 

Small pearl-bordered fritillary © Ramsay Young

Small pearl-bordered fritillary © Ramsay Young

We will look for this BAP priority species as well anyway, probably more likely to be found in the damper areas nearer the loch shore, and although a little early in the season, may well be present if the weather is warm between now and then (fingers crossed).

 

Brig o’ Turk village has a small café, with another restaurant a little bit further along the road towards Aberfoyle, and of course Callander and Aberfoyle both have plenty of  places to eat and drink either before or after the walk – you could even bring a picnic as we’re almost certain to have gloriously sunny weather on the 24th! See you then.

 

Heather Young.

 

 

 

 

 

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