Eurasian otter (Lutra lutra) prey selection in response to a variation of fish abundance

摘要: Abstract In 2001 and 2002 we studied Eurasian otter (Lutra lutra) fish selection in southern Italy by comparing diet (805 analysed spraints) with availability, estimated electrofishing. The surveyed river was dominated cyprinids, particularly chub (Leuciscus cephalus), roach (Rutilus rubilio) bleak (Alburnus sp.). Roach were the most common prey recorded spraints. Otters ate mainly small (total length < 90 mm). Chub widely consumed according to abundance, whilst consumption not proportionate their availability. selected both responded a decrease availability (–27.3%) increasing frequency of rather than switching an alternative prey. Despite high seemed be markedly avoided otters. We hypothesized that differences microhabitat may influence susceptibility cyprinids predation. possible effects on community...