Butterfly Islands: May 2015

Wednesday, 13 May 2015

Visiting My Favourite Island Sites.

The prospect of a warm and sunny spring day encouraged me to visit a few of my favourite locations on the Island.First stop the National Trust owned Whiteways Quarry now a Viewpoint Carpark, commanding majestic views over our south-western coast.Here at the old quarry, a fantastic assortment of spring butterflies are protected by the shelter of Afton Down and today there was another new species to see.The Small Blue is our smallest butterfly and lives in very compact colonies.The males are usually the first to emerge and can be recognized by the dusting of blue scales on their upper wings.At least three were present today.Also here were a pair of mating Wall Brown butterflies.This species has declined in the UK over the years but can still be seen in good numbers on the Isle of Wight.

Leaving the carpark for a drive south along the coast to Wheelers Bay at Bonchurch, for another look at our Glanville Fritillaries which are the first in the country to appear at this location.Although at times the cloud shaded the sun today I counted four individuals.Many more will emerge along our southern coast during May.

Finally a steep walk up to Bonchurch Down that overlooks the village of Bonchuch and the town of Ventnor.This south facing Down is one of the prime places on the Island for the spectacular Adonis Blue butterfly and a walk along the Downs' steep sides produced a first male Adonis.

Saturday, 9 May 2015

Busy in my Local Copse.

A good selection of butterflies today at my local copse,all enjoying the spring flowers.Very belatedly I have seen an Orange Tip for the first time this year.In fact they were out in good numbers although the males were always in a hurry and never seemed to settle close by.However the females had egg laying on their minds and I observed them fluttering from plant to plant getting on with the business.

Thursday, 7 May 2015

Our Special One on the Wing.

Following several days of gale force winds along our Island coast,today we had just a lively breeze with plenty of sunshine.An ideal opportunity to see the newly emerged Glanville Fritillaries and an early start this morning produced one very new butterfly seeking a sheltered sunny spot away from the breeze.

Tuesday, 5 May 2015

Glanville Fritillary Pupae.

The first adult Glanville Fritillary butterfly of 2015 was seen on the Isle of Wight yesterday, the 4th May and hopefully during this month many more will emerge along our southern coast.

A sight that is not normally seen however is the fritillaries' pupal stage,particularly in the wild. Of course like other species of butterfly some are reared in captivity and sadly we have collectors from the mainland visiting our Glanville sites in the early spring to take caterpillars.So to discover pupae in their natural habitat is very satisfying and uncommon.

Once the full grown caterpillars have dispersed from their communal nest in April each will find a suitable place to pupate.The three pupae or chrysalises found today were attached by their pads of silk to the underside of small stones.Pupa length 13-14mm. This stage will last about three weeks.

Monday, 4 May 2015

Yet Another New Arrival.

Now that May is here new species are appearing at a fast rate and today at Whiteways a Brown Argus made a first showing.

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.