Record number of rare butterflies found in Dorset

Chalkhill Blue butterfly by Ken Dolbear

After years of declining butterfly populations, a recent survey by the Dorset Wildlife Trust (DWT) has found a record number of a rare butterfly species on the Upton Heath nature reserve.

A Promising Start

A group of DWT volunteers surveyed Upton Heath in July, and counted 101 Silver Studded Blues in just a few hours; a new record for the site. Silver Studded Blues are a rare species only found on heath land, limestone grassland and sand dunes.

After the announcement by Sir David Attenborough earlier in the year that UK butterfly numbers were at an all-time low, the warm start to the summer has provided a much needed boost to butterfly populations.

Bill Shreeve, from the Butterfly Conservation, said; “The best performer has been the dark green fritillary; the combined annual average count for this year is 728, a 373 per cent increase. On Fontmell down the average count since 1980 has been 20 and this year was up to 443.”

Upton Heath and Fontmell down are not the only reserves where butterflies are thriving. DWT’s Tout Quarries on Portland, has been alive with butterflies this summer. There have also been several sightings of the calcareous form of the Silver Studded Blue, which is unique to Portland.

Significant number of "blues"

Sam Hamer, Dorset Wildlife Trust Conservation Officer, said: “The butterflies have definitely appreciated the warmer start to the summer this year, and we have already seen a significant increase in the numbers of many different species. At Tout Quarries, Chalkhill blues, Adonis blues, and even Small Blues have all been doing really well.”

How you can help

You can help Butterfly Conservation monitor the overall butterfly population by visiting www.dorsetbutterflies.com/recording/white-holes.html

Silver Studded Blue, Male by Ken Dolbear

Silver Studded Blue, Male by Ken Dolbear

Adonis Blue by Ken Dolbear

Adonis Blue by Ken Dolbear