New Year hunt for rare butterfly eggs

Brown Hairstreak butterfly
Brown Hairstreak butterfly

Families in Bicester are invited to work off those Christmas mince pies and see in the New Year searching for rare butterfly eggs.

For the last 10 years, Butterfly Conservation’s Upper Thames Branch have been organising New Year’s Day egg hunts to monitor the local population of Brown Hairstreak butterflies.

Brown Hairstreak egg

Brown Hairstreak egg

It is the largest and brightest of the UK’s five native hairstreaks, with rich, dark chocolate-brown upperwings and an orange ‘tail’.

The females have a bright band of golden-orange across their forewings and both sexes have an orange-yellow underside, with white ‘hairstreak’ lines across both wings.

Despite its beauty and a flight period lasting from June until September, this butterfly is rarely seen. Adults spend the majority of their lives high up in treetops, with the females only descending to feed and lay tiny white eggs.

Chairman of the Upper Thames Branch, Nick Bowles, said: “The eggs are very small, but once you know what you’re looking for, you begin to spot them quite quickly.

“This is a unique way to celebrate the New Year and we teach all newcomers about what they’re looking for and how to search for them. It’s almost like a treasure hunt but as well as being great fun it’s also contributing to the conservation of this beautiful, elusive butterfly.”

The ‘New Year’s Day Egg Hunt’ is taking place at Otmoor, near Beckley, a site managed by the RSPB. They have been working in collaboration with Butterfly Conservation, agreeing to plant more hedges if volunteers from the branch carry out annual butterfly surveys.

If you would like to attend, visit