Pictured: large tortoiseshell, Nymphalis polychloros
200-year trend in Cambridgeshire: Decline.
Modern records
This species was once resident and widespread across the south of the UK, including Cambridgeshire, but it has now been virtually extinct in the country for around 50 years. That being said, it is a strongly migratory species and occasional specimens are still seen. Recent sightings of larvae are also positive but it still has a long way to go to reach historical numbers. Victorian collectors found it to be extremely common amongst woodlands but Dutch elm disease destroying the larval foodplant, climate change and other factors have been suggested as reasons for its decline.
National records map
Large tortoiseshell national records map: https://species.nbnatlas.org/species/NHMSYS0000516575