While rummaging through our species lists looking for ammunition to throw in the direction of Planning Application 20/00379/OUT, we found a 2018 record of a small heath (Coenonympha pamphilus) hidden in the Lepidoptera section. The small heath is the park’s third UK BAP Priority Species of butterfly.
The small heath is an inconspicuous little butterfly that flies only in sunshine and always closes its wings when at rest. Despite its name, it can be found in a variety of habitats but it has a particular liking for grassland and places its eggs singly at the base of blades of fescue, bent or meadow grasses or in nearby vegetation.
1. Adult small heath feeding on ribwort plantain; 2. caterpillar
The caterpillars, wearing green striped camouflage, spend most of their time hidden away at the bottom of a tuft of grass, coming up at night to feed on the growing tips where the grass is soft and tender. Depending on conditions, the caterpillars will either pupate and produce adults in the same year, or they may overwinter and pupate the following spring.
A small heath keeps its wings closed when at rest so this is a picture is of a dead specimen and if you look closely, you can see the pin.
Small heath adults live in distinct colonies and rarely venture far from the group. Their flight pattern is low and fluttering and they seldom come to rest further than a metre from the ground. Perhaps there is such a colony of small heaths somewhere in the park low-flying over our meadow grasses; we will have to send out search parties in the summer.
Butterfly Conservation priority: High
Section 41 species of principal importance under the NERC Act in England Section 42 species of principal importance under the NERC Act in Wales Northern Ireland Priority Species
UK BAP status: Priority Species.
Header picture: Small heath (Coenonympha_pamphilus) by Charles J Sharp (CC BY-SA 4.0) Wikimedia commons