Butterfly Islands

Saturday, 8 July 2017

Good Season for Silver-washed.

It seems to be an excellent season for the Silver-washed Fritillary. Good numbers are to be seen in our woodlands and if lucky the odd female Valezina form could turn up.It is estimated that one in seven females have this attractive appearance.

Tuesday, 27 June 2017

Summer Butterflies Enjoy the Bumper Bramble Bounty.

There were a prolific number of butterflies at Walters Copse today.The most impressive were the Silver-washed Fritillaries and the White Admirals.These and many other species were busily feeding on the bramble flowers that seem to be abundant in the copse this year.Although male and female Silver-washed were on show I was not lucky enough to see the female Valezina. In the south of England it is estimated that up to 15% of the females are of this beautiful form.

Monday, 26 June 2017

Dark Green Fritillaries On Speed.

With the season generally over two weeks early this year I made a first visit to West High Down in the hope of seeing a Chalk-hill Blue.I have not yet recorded this blue earlier than in the month of July and I was optimistic of a June sighting.Alas no Chalk-hill Blue today and with an unsettled and rainy forecast for the rest of the week I think that it will be July again for this last remaining blue of the season.

Nevertheless another butterfly of our downland is on the wing now,the Dark Green Fritillary. These large fritillaries spent most of their time flying at high speed across our downs,only briefly stopping it seems, for a quick top up on the Giant Thistle flowers that are scattered about.In fact at the moment there seems to be very few Giant Thistle flowers in bloom so getting any sort of view of this butterfly is limited.

Friday, 23 June 2017

All Change.

After a prolonged spell of hot and sunny weather, yesterday began fresher,windy,and cloudy.These conditions lasted all day so the prospect of seeing any butterflies in my local wood seemed to be limited.Thankfully the temperature was up at around 20C so activity was moderate despite the lack of sunshine.Marbled White numbers have increased dramatically since last week as too Meadow Brown and Ringlet.I was very pleased to see several White Admiral and also a first sight this season of Small Skipper.

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.