Local naturalist Terry Lyle had a surprise during a regular butterfly survey in Tower Hamlets Cemetery Park on 21st May. He found a Small Blue, a rare butterfly usually found on chalk downlands and never before recorded in inner London.
The Small Blue is Britain’s smallest butterfly. Its caterpillars feed on Kidney Vetch, a yellow-flowered relative of clovers, which likes dry, chalky soils. There are a few well-established partches of Kidney Vetch in Cemetery Park, and it was on one of these that the butterfly was seen. Having caught the butterfly to confirm the identification and take photos (see above), Terry released it unharmed back in the same area.
The nearest sites where the Small Blue is know to occur are on the southern edges of London in the boroughs of Sutton, Croydon and Bromley, or in Hertfordshire. While some butterflies regularly travel long distances to find suitable habitat, the Small Blue rarely travels more than a few hundred metres. It is therefore really astonishing that one should appear many miles away from its normal haunts.