Blean Woodland - Heath Fritillary

Blean Woods - Wildlife
Heath Fritillary Butterfly
( mellicta athalia)

The heath fritillary is a small orange, brown and black butterfly which can be seen in the woods on warm sunny days between the end of May and July.(click on the butterfly to see a clearer picture.) In 1985 the butterfly was described as "probably the most endangered butterfly in Britain now confined to a handful of sites in SW England and Kent". Since then conservation organisations have worked hard to protect the populations and in the Blean numbers have increased.

The Life Cycle of the Heath Fritillary.

Adult butterflies emerge from their pupae at the end of May and June. When flying both males and females usually keep close to the ground and only occasionally fly over tall trees and shribs. The butterflies feed on nectar from a variety of plants especially brambles and buttercups.

In the Blean the female will only lay their eggs on common cow-wheat (Mealampyrum pratense). The eggs are pale yellow and turn dark grey two days before hatching. They are laid in batches of between 60 and 100 eggs. The eggs are laid close to the ground and hatch after 15 to 23 days.

The caterpillars are pale cream with a dark head at first but become dark brown. In August or September the caterpillars stop feeding and form protective hibernaculae where they spend the winter. In spring the larvae will bask in sunlight. The larvae pupate in May and June and pupae for 2 to 3 weeks before emerging.

Conservation of the Heath Fritillary.
A number of activities within the Blean have helped protect the Heath Fritillary Butterfly;

Coppice management. This traditional technique involves cutting trees on a 25 year cycle. It produces woodland with areas of trees in different stages of growth. This provides a wider variety of habitats than mature woodland. The caterpillars food plant, cow-wheat is only found in such coppiced areas.

Ride management. Rides are the wide pathways which can be found in woodlands. Rides have played an important part in the conservation of the Heath Fritillary butterfly because they allow them to move from one area of woodland to another increasing their distribution.