Butterfly Islands: Bleak Down

Showing posts with label Bleak Down. Show all posts

Wednesday 16 July 2014

Graylings Back on Bleak Down.

I hoped that the Graylings were out on Bleak Down by now and made the walk to their usual site on the Down.The area is one of the few remaining stretches of heathland on the Island and with the heather now in flower it makes a colourful sight.After some time of searching I at last found a Grayling. Obviously I was somewhat early to see the colony, so hopefully in another week numbers will have substantially increased.
2017 update. A visit to this site today the 5th August discovered no Graylings. The area of past activity has now been overgrown with grasses and although flowering heather still remains in places, there is no bare open ground.

Wednesday 24 July 2013

The Bleak Down Graylings.

Today's visit to Bleak Down close to the village of Godshill was to see the Grayling. This butterfly is a good example of 'cryptic camouflage', as when at rest on the ground the underside blends perfectly with the background.The Grayling lives in rather compact colonies and a walk across a section of the Down will throw up these fast flying butterflies.The female is larger than the male and more brightly marked.Taking a close look in the heather or grass one can find the female carefully laying one egg at a time on a blade of grass or on a heather flower stalk.

Monday 10 October 2011

Graylings on Bleak Down

On the 30th July we made a visit to Bleak Down on the Isle of Wight.one of the few sites,and perhaps the best site on the Island for the Grayling butterfly.The habitat is ideal for this species and good numbers were seen.The Grayling likes to lay a single egg on a grass stem on open ground as shown in the first photograph.The caterpillar will then overwinter.This butterfly is single brooded.

Grayling habitat on Bleak Down

The Adonis Blue

The Large Tortoiseshell

It seems the general view on the status of the Large Tortoiseshell in Britain is that it is now extinct as a breeding butterfly.
It is a butterfly of woodland edges and hedgerows that abound in willows,elms,and poplars.These trees are used by the adult to lay its eggs and this single brood appears in July and August.The emerging butterfly then hibernates over the winter in log piles and hollow trees until the next spring.
On the Isle of Wight sightings are more often than not made from early March to April.Have these butterflies overwintered on the Island or have they come from the continent where it is common?
Any sightings made in July/August pose the same question.Another explanation could be that captive-bred releases are responsible.Only the discovery of eggs and caterpillars will probably answer these questions.

I can now report that evidence has been found of breeding just along the coast at Portland in Dorset (June 2020) and again at the same location in the summer of 2021.

The Glanville Fritillary

This elegant butterfly is mainly confined to the crumbling undercliffs and chalk downs of the Isle of Wight.It is also found on the Channel Islands and at one or two isolated colonies on the British mainland.In Britain the Glanville Fritillary is at the extreme north-western edge of its range.On the continent it is readily found in flowery habitats.
Around the southern shores of the Isle of Wight the cliffs constantly erode causing them to slip away and provide perfect conditions for new growths of the butterflies laval host plant,Ribwort Plantain.
The eggs are laid to the underside of the leaves of this plant and normally hatch after about three weeks.The resulting caterpillars live together in communal webs spun over the plantain.In the autumn they hibernate and recommence feeding in the spring,eventually dispersing to prepare for pupation.
The adult butterfly is on the wing from May to the end of June with the female being larger than the male.They will feed on,amongst other things, Birds-foot Trefoil and Thrift.

The Wall Brown

On the Isle of Wight in particular,the Wall Brown is a butterfly of field edges,coastal cliffs and dunes,and rabbit-grazed downland.
The male is territorial and spends much of the time patrolling and basking on the ground.
The female,which lacks the males conspicuous dark sex brand across the forewings,is larger.The undersides of both sexes are beautifully cryptic when at rest.
The Wall Brown generally produces two broods a year,the first from late April until late June and the second from mid-July to mid-September.