We wish to report the first laboratory confirmed cases of disease caused by squirrelpox virus (SQPV) in wild red squirrels ( Sciurus vulgaris ) from Wales. Following a long-term grey squirrel ( Sciurus carolinensis ) management and control programme on the island of Anglesey, north Wales, a series of red squirrel translocations from a number of British captive red squirrel collections between 2004 and 2013, reinforced a natural population expansion, from a low of 40 in 1998, to around 700 animals today.1 Since 2009, small numbers have dispersed over the Menai Strait via either of the two bridge links or by swimming the Menai Strait to the Gwynedd mainland, where they have bred and colonised several coastal woodland locations, including the Faenol woodlands and Treborth Botanical Gardens. Here, both locations have small resident populations, often sympatric with small numbers of grey squirrels which are widespread in the surrounding landscape. Historical serological studies revealed two-thirds of the healthy Treborth grey squirrels tested were positive for …