Butterfly Islands

Wednesday, 11 July 2018

Butterflies on New Forest Heathland.

Arguably the three major butterflies of New Forest Heathland are the Silver-studded Blue,the Grayling,and the Dark Green Fritillary.Yesterday on Beaulieu Heath I saw the first two species.The attractive Silver-studded Blue has been on the wing for a while now although many are still in excellent condition.It is also the time for the first Grayling to appear and they can be found on any bare patch of heathland in particular.

Beaulieu Heath seen from Crockford Stream

Monday, 9 July 2018

Back on the Bridleway to West High Down.

Another hot and sultry day and a return visit to the bridleway that leads up onto West High Down.Thankfully living very near to the coast a sea breeze relieved some of the heat and below the Down it became quite brisk at times.

I had better luck today in my quest to see the first Chalk-hill Blues of the year.However they had already been reported from Brook Down situated just to the south.It seems that those on Brook Down are always on the wing in advance of the Blues of West High 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.