Blues for the Blues

Blues for the Blues

By: Jean Turner
Added: 22 October 2011

Friend of Fairlynch Museum Jean Turner champions a beautiful insect whose habitat just a few miles from Budleigh Salterton is under threat.

The East Devon Commons is the site of the finest lowland heath in Britain, supporting a wide variety of wildlife, some of which is very rare. For this reason the area has been designated as a site of Special Scientific Interest.

One of these rare species is the beautiful Silver Studded Blue butterfly (SSB) whose adults grace the heathland during the months of June and July. The male’s upper wings, pictured above,  are a deep blue with clear white fringes which contrast with the spotted silvery underwings, bordered by a band of orange which is punctuated with black and silvery blue spots. These “silver studs” are found on no other butterfly. The females, by contrast, have brown upper wings and darker underwings, but also have the silver studs.

They are very weak fliers and live in discreet colonies on low heathland where young heather-growth, especially Bell Heather, is interspersed with patches of sandy ground. The heather provides a food source for the caterpillars and nectar for the adults. The bare sandy ground, besides helping to provide a warm environment, also encourages the Black Garden Ant (lasius niger) to flourish. The caterpillars produce a sugary substance which attracts the ants who carry the caterpillars into their underground nests. Here the caterpillars pupate and are protected against predators. Even at emergence of the adults, ants remain in attendance, licking up the droplets of sugar solution found on the wings and body of the butterfly. This, as in some other blue butterflies, is thought to be an essential element of the life cycle.

The heathland habitat is now very rare and many colonies have been lost in recent years. On the East Devon Commons the colonies remain small and there is a constant battle to manage the heath in order to maintain a good habitat for them.

Clinton Devon Estates have owned the Commons since the seventeenth century and their managers work towards creating a healthy environment for all heathland wild life. They rely on the expertise of various organisations to recommend the kind of management needed.

Each year, volunteers from Devon Butterfly Conservation make regular visits to the areas where SSB colonies are found, to count their numbers and asses the adequacy of the habitat. These are then collated and management recommendations made to the wardens of Clinton Devon Estates.

Until recently there has been little funding for this work to be done. Now however the East Devon Pebblebed Heath Conservation Trust has been established and Higher Level Stewardship funding has been obtained to maintain this valuable expanse of heathland. Those who walk regularly on the commons will no doubt have witnessed some changes in recent years, with some clearance of land and the presence of cattle roaming the heath — all to promote its regeneration.

There has been some controversy concerning the way in which the heath is managed to promote the continued existence of insects like the SSB. The agreed best management technique for invertebrates is to scrape areas to allow new heather to regenerate but a moratorium was placed on scraping for the whole of he commons by the archaeologists to protect possible prehistoric sites.

The ban will no doubt have a deleterious effect on the SSB numbers. This year numbers were down by 50% from last year. This is partly due to the severe cold conditions in the winter and the poor weather in the flight season, but it is also largely due to the continuing shrinkage of the habitat for this beautiful butterfly.

Do the archaeologists want the whole of the commons to be left for their interests alone? Can’t some compromise be made or some surveying be done to establish which areas are of prehistoric value so that other areas can be managed for insects?

Jean Turner is Co-ordinator for Silver Studded Blues for Devon Butterfly Conservation http://www.devon-butterflies.org.uk/

More pictures of these beautiful insects can be seen at http://budleighbrewsterunited.blogspot.com/2011/10/blues-for-blues.html


Fairlynch Museum

Fairlynch occupies an imposing position on a bank overlooking the junction of Fore Street and Marine Parade. It is one of the very few thatched museums in the UK. The building......

Museum home

Fairlynch Museum events

more events