Insight into the Dietary Habits of the Eurasian Otter, Lutra lutra, in the East of Algeria (El-Kala National Park)

In 1997, faeces samples (spraints) (n = 175) from the European otter (Lutra lutra) were taken in seven localities of the El-Kala region. This is a restricted eco-geographic complex in which
freshwater hydrographical systems, comprising rivers, ponds and wet coastal zones (brackish
lagoons, shipping channels), are highly interwoven.
The frequency of occurrence and relative abundance of consumed taxons were calculated
on the basis of 493 identified prey. Fish made up more than 88% of the otter’s catch (relative
abundance), with a strong predominance of Pseudorasbora parva, Luciobarbus callensis and
undetermined Cyprinidae. Anuran amphibians made up 9% of the prey. The remainder were
represented, in order of significance, by mullets, eels (Anguilla anguilla), bleaks (Alburnus
alburnus), perciformes, gobies, insects, birds, crustaceans, etc. However, Cyprinidae, the eel
and the barbel dominated in terms of ingested biomass. The otter’s diet varies with local conditions: lagoons and channels have marine or migratory fish; rivers are dominated by barbels; ponds by Cyprinidae. Finally, small-sized fish (topmouth gudgeon and barbel) dominated the diet in terms of numbers: 62% are smaller than 12.5 cm. The introduction of the
topmouth gudgeon into the region could have catastrophic consequences for endemic fish,
such as Pseudophoxinus callensis.