British butterflies to spot

Swallowtail

This is one of our rarest and most spectacular butterflies. The British race britannicus is a specialist of wet fenland and is currently restricted to the Norfolk Broads. Here the adults can be seen flying powerfully over open fen vegetation, stopping to feed on flowers such as thistles and Ragged-Robin.

The butterfly probably declined within its range during the twentieth century but has benefited over the last few decades from conservation management aimed at increasing open fen vegetation. There are also scattered records of migrants of the continental race.

What it eats Native British Swallowtails feed only on milk-parsley. Occasional migrants of the continental race gorganus use a variety of umbellifers such as wild carrot and wild angelica.

Where to find it In the Norfolk Broads, in vigorous milk-parsley. Swallowtails prefer areas of mixed fen with sedge or reed.