Food Availability and Diet Composition of the Eurasian Otter Lutra lutra (L. 1758) in Saharan Aquatic Ecosystem, Dam of Djorf Torba's, Bechar-Algeria

The European Otter, Lutra lutra (L.1758) diet has been studied during two seasons (winter-spring) in a Saharan aquatic ecosystem in south-western part of Algeria. The inventoried fish fauna is composed of eight species namely barbell (Luciobarbus pallaryl), pseudorasbora (Pseudorasbora parva), carassin (Carassius carassius), common carp (Cyprinus carpio), silver carp (Hypophthalmichthys molitrix), large mouth carp (Aristichthys nobilis), common bleak (Albumus albumus) and tilapia (Oreochromis niloticus). A total of 189 faeces samples (spraints) were collected from January to June which helped in identifying 419 preys divided into five categories (arthropods, fish, amphibians, reptiles and birds). The relative frequencies of occurrence, abundance and biomass of preys have been calculated. The Eurasian Otter feeds on a variety offish species, which constitute about 80% of relatives occurred and 89% of total biomass ingested by this animal where the only dominant species was the barbel, as an endemic species which remains the favourite prey of the Mustelidae. Additionally, other preys completed the animal's diet such as arthropods, amphibians, reptiles and birds. With regards to the seasonal variations, the barbel remains always the most abundant prey.