A rare oil beetle is breeding again at Castlemartin after nearly 60 years

A short-necked oil beetle is breeding again at Castlemartin range in Pembrokeshire, the first such sign in Wales in nearly 60 years. The Guardian reported on November 1, 2026, that Natural Resources Wales confirmed the find. Adults are stubby and can secrete an oily yellow-orange substance from their knee joints when alarmed. The larvae hitchhike on solitary bees with hook-like feet, then eat pollen in the nest until they emerge. An adult lives about a year. NRW says only a handful of UK sites suit the species, and that about one in 10,000 larvae reach adulthood. It is classed as nationally rare.

The beetle was rediscovered in Devon in 2006, with later populations in the Hebrides and on Salisbury Plain. Buglife reported it at the Pembrokeshire site in 2020. Surveys in 2022 and 2025 found only dead adults, which raised doubts the local population was still viable. The 2026 survey found larvae distributed in a pattern that suggests young from a larger batch had thrived. Anna Hobbs of the Bumblebee Conservation Trust called the breeding evidence exciting and said the work has to serve the beetle and the solitary bees together. The project sits inside Wales's Natur am Byth recovery programme, which also covers the shrill carder bee, goldilocks aster, and pale dog violet. The news is larvae after two empty surveys. It is not a population total.