Thanks to initiatives such as the UK Butterfly Monitoring Scheme (UKBMS) and Butterfly Conservation’s Big Butterfly Count (the UK’s biggest citizen science survey), butterflies are among the best recorded biological groups in Britain. The wealth of data on these insects is invaluable not only for monitoring long-term trends in populations, but also for identifying the impacts of different drivers of change, such as habitat loss and climate (Fox et al. 2022).
Exactly why certain caterpillars glow brilliantly under ultraviolet light remains mysterious, but this trait could help to open new avenues for detecting some of our most elusive species; Gareth Tilley, Caroline Bulman and Steven Lofting provide an introduction to this novel field of research and its potential value in monitoring British butterflies and moths.