Researchers will attempt to rear swallowtail butterflies from eggs frozen in liquid nitrogen, in a pioneering project that could help protect species at risk of extinction.
The trial will involve freezing eggs of captive-bred European swallowtails at –196C, then thawing them to see if they can develop successfully into butterflies. Their survival will be compared with that of unfrozen eggs.
If successful, the method could be used to preserve the eggs of the British swallowtail (Papilio machaon britannicus), a unique subspecies now confined to the low-lying Norfolk Broads. Rising sea levels threaten its last habitat, and 2024 marked its worst year since records began.
The study is being carried out by Anglia Ruskin University in partnership with Jimmy’s Farm & Wildlife Park and the conservation biobank Nature’s Safe.
Dr Alvin Helden of ARU said: “Cryopreservation is a promising tool for supporting conservation efforts, but we believe this is the first time it has been attempted with butterflies.”
Jimmy Doherty, founder of Jimmy’s Farm, added: “This project could make a real difference in protecting the British swallowtail for generations to come.”
Nature’s Safe said the research could advance cryopreservation methods not just for butterflies, but for pollinators and invertebrates more widely.
