The diet of denning female Europeanpine martens (Martes martes) in Galloway Forest District, South West Scotland, Great Britain

Populations of Europeanpine marten (Martes martes) across Great Britain declined dramatically during the 18th and 19th centuries due to deforestation and human-wildlife conflicts. Pine marten recovery from their northern Scottish stronghold is limited following reintroduction in Galloway Forest District, south-west Scotland, in the 1980s. With suggestions that martens have influenced red squirrel population increases in neighbouring Ireland, marten reintroduction efforts are a priority in Great Britain. Reintroduction requires establishment of recruiting populations that depend on suitable food availability to meet the associated higher energy demands of recruitment. We, therefore, investigated the diet of reproductive denning female martens during denning (March-April), and the mixed sex population in summer for the first time in Galloway. Scats (n=114) were analysed from clumps collected from occupied artificial den boxes in 2015 and 2016, as well as genetically verified scats (n=44) from summer transects in 2014. We compared our results with other Scottish studies and found that carrion frequency of occurrence and biomass of prey ingested differed most significantly between the regional mixed sex spring diets and the diet of denning females in Galloway. Anurans, birds, and small mammals were the likely substitution of carrion; we hypothesise that these differences are related to sex-specific behaviours and scavenging risk. We, therefore, suggest that there are differences in the diet of denning female martens compared to mixed sex spring populations and that future translocations should consider abundances of anurans in Galloway, and even more importantly than before, small mammals and birds across Great Britain.