Photo © Mike Wall

Small Tortoiseshell

Aglais urticae

Checklist Number
59.027 [B&F: 1593]

Verification
Record will be accepted (subject to date and location checks)

Classification

Family:Nymphalidae
Subfamily:Nymphalinae
Genus:Aglais
Species:urticae
Authority:(Linnaeus, 1758)

One of our most familiar and widespread butterflies, common in gardens, rough ground, farmland and downland throughout much of the British Isles, mainland Europe and Fennoscandia. It has however suffered a significant decline in abundance, especially in the south, over the past four decades, various theories for which have been proposed. The most likely is increased parasitism by the fly Sturmia bella, a common species on the continent which has now established itself in the British Isles. Although the fly attacks related species, such as the Peacock and Red Admiral, it is believed that the lifecycle of the Small Tortoiseshell is better-synchronised with that of the fly and it is therefore more prone to parasitism. Abundance indicators between 1976 and 2014 showed a decrease of over 70%; however, there are signs that this is reversing, with the past decade (2005-2014) showing a 140% increase. This pattern appears to be apparent in Hampshire with the years 2013-2015 having the highest annual totals on the database.

Wingspan 50-56 mm. The second generation adult hibernates overwinter in trees, caves and outbuildings. The larva feeds on Stinging Nettle and Small Nettle.