Researchers are set to attempt to breed swallowtail butterflies from eggs that have been frozen in nitrogen at -196°C, in a test to determine if freezing techniques could aid the long-term conservation of the UK's biggest indigenous butterfly.
In a groundbreaking project, scientists will freeze eggs of farm-raised European swallowtails in liquid nitrogen and then strive to raise butterflies from the unfrozen specimens, comparing their results with individuals reared from eggs that have remained unfrozen.
Should this approach work, it could lead to genetic material of the Papilio machaon britannicus being stored to bolster long-term conservation strategies, such as breeding programmes and translocation efforts.
The Plight of the Native Butterfly
Papilio machaon britannicus is a distinct variant but its habitat is shrinking and it is vulnerable to extinction, confined to marshy areas of the East Anglian wetlands likely to be overwhelmed by rising seas over the coming decades. In 2024, it experienced its most challenging season since scientific records began.
Collaborative Efforts in Cryopreservation Research
Freezing techniques for Lepidoptera is being tested by scientists from a university in collaboration with a conservation center and a non-profit specialising in biobanking for wildlife.
“Our project will combine fieldwork and laboratory work to determine whether we can develop a reliable method for safeguarding the British swallowtail’s genetic material by using its closely related, but less endangered, continental relative. Freezing preservation is a promising tool for supporting conservation efforts, but we think this is the first time it has been attempted with butterflies.”
A wildlife park founder stated: “Our commitment to the study of insects, and especially protecting butterflies, means this project is a ideal match for us. Working together with academic partners and non-profits allows us to apply our expertise to work that could make a real difference in safeguarding the British swallowtail for generations to come.”
“The initiative is highly important for the advancement of freezing methods – not only for the native butterfly, but across pollinators and invertebrates as a group.”
Future Implications
Should it work, this technique could set the stage for similar applications in preserving threatened insects and enhancing worldwide ecosystems.
