On the Hunt for one of Britain’s Rarest Butterfly’s: The British Swallowtail

June marks the halfway point of the year, sitting perfectly between spring and summer. It’s one of the most exciting months for wildlife lovers, as the countryside is bursting with life. Birds are busy raising young, wildflowers are in full bloom, and countless insects are taking to the wing – making it one of the best times to explore the UK’s incredible native wildlife.

Among them is one particularly special species: the British swallowtail.

With striking cream-yellow wings marked by bold black patterns, flashes of blue and orange, and elegant tail-like extensions on its hindwings, the British swallowtail is impossible to mistake. As the UK’s largest resident butterfly, seeing one in flight is an unforgettable experience. Despite its size and beauty, however, it has one of the most restricted ranges of any British butterfly, surviving naturally only on the Norfolk Broads. Here, its caterpillars depend entirely on milk parsley, a wetland plant found in the Broads’ unique network of fens and reedbeds. 

After a couple of hours on the road, conditions weren’t exactly ideal. Although late May had brought warm weather, temperatures had dropped again by early June and a stiff breeze swept across the marshes. Butterflies are at their most active on warm, sunny and sheltered days, so expectations were cautiously optimistic.

But several hours of searching eventually paid off…

The Broads delivered plenty of other wildlife highlights too. Hobbies swept low over the reedbeds hunting dragonflies, longhorn moths danced in the dappled undergrowth, and an adder was even seen quietly retreating from the path to the low reeds – reminders that this remarkable landscape supports an extraordinary diversity of wildlife.

Back at Jimmy’s Farm & Wildlife Park, the next stage of the project is already taking shape. Young milk parsley seedlings are growing well in the greenhouse, ready to be planted out in suitable habitat as they mature. Alongside this, exciting work is continuing around breeding European swallowtail populations, egg-freezing viability and the wider scientific research that will help shape the future of the project.