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  • chalkhill blue

chalkhill blue

Pictured: chalkhill blue, Polyommatus coridon

Notes from Jenyns: Found in profusion on the Devil’s Ditch in July; also in Hinton Chalkpits & on Alington Hill. ~ The females appear later than the males, & are much less frequent. ~ Gogmagog Hills.

200-year trend in Cambridgeshire: Little change overall, despite a near catastrophic decline 40 years ago.

Modern records

 This species is still only found on a few chalk grassland sites in Cambridgeshire, with most locations matching the historical literature, including Devil’s Dyke, as recorded by Jenyns. Changes in management at Devils Dyke in the 1980s saw numbers dwindle close to extinction, but concerted efforts have reversed that decline and the chalkhill blue is now counted there in the thousands. The species has also naturally spread to recolonise Fleam Dyke and the Roman Road and has been introduced to the limestone grassland at Barnack Hills and Holes. 

National records map

Chalkhill blue national records map: