Butterfly Islands

Sunday, 1 July 2018

A Good Season for the White Admiral.

This year seems to be a good time for the White Admiral.My visits to Bouldnor Forest during the last couple of weeks has seen a steady increase in their numbers and yesterday I encountered several alighting on the tracks. This elegant butterfly of our woodland loves to glide in and out of the sunny glades nectaring on bramble flowers and resting on a shaded leaf.

Monday, 18 June 2018

Plenty of Summer Butterflies on Show.

Butterfly numbers have dramatically increased now that the summer butterflies are on the wing.Today in Bouldnor Forest Marbled White and Silver-washed Fritillaries were the two new species.The White Admiral is now even more evident in the forest rides as they enjoy the bounty of bramble flowers.

Friday, 15 June 2018

White-letter Hairstreaks at Towngate.

I first noticed a White-letter Hairstreak flying near to the top of the Towngate elm tree last Tuesday the 12th June.Unfortunately none decided to investigate the lower branches at the time.I had better luck today as after a patient wait at least two hairstreaks came to eye level.The advantage of this site is a footbridge that spans the stream below.The elm is planted on the bank of the stream and therefore standing on the bridge gives access to the branches halfway up the tree.(See last years blog entry)

Thursday, 14 June 2018

A Common Blue Outshines the First White Admirals.

Following a wet and windy morning the weather picked up this afternoon.This made a walk through Bouldnor Forest very pleasant and it was not long before I saw my first White Admiral of the year.In fact I counted a total of three fresh individuals and all were very active in the sunshine.

It was not only these colourful summer butterflies that stood out as there cannot be a butterfly arguably more stunning than a female Common Blue.

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.