The swallowtail butterfly is yet another species reliant on the effective management and conservation of our fenland areas and, as such, is confined mainly to the Norfolk broads.
In particular, it feeds exclusively on milk parsley which was more widespread throughout the fens of Cambridgeshire however as habitat has been lost through agriculture and development over the last century, so too have the swallowtail butterflies.
The swallowtail butterfly is unmistakable due to its size (being our largest), black and yellow pattern plus striking blue hind which centres around a large red spot, and, probably most recognisably, it's distinctive tail shaped like that of a swallow.
Not only is this our rarest butterfly, but you can only realistically see the swallowtail in any abundance for one month of the year - June. By late summer they have all but disappeared.