Factors associated with the differential distribution of cetaceans linked with deep habitats in the Western Mediterranean Sea.

Deep-habitat cetaceans are generally difficult to study, leading to a limited knowledge of their population. This paper assesses the differential distribution patterns of three deep-habitat cetaceans (Sperm whale-Physeter macrocephalus, Risso's dolphin-Grampus griseus & Cuvier's beaked whale-Ziphius cavirostris). We used data of 842 opportunistic sightings of cetaceans in the western Mediterranean sea.

Using opportunistic sightings to infer differential spatio-temporal use of western Mediterranean waters by the fin whale.

The fin whale () is a cosmopolitan species with a resident population in the Mediterranean Sea. Due to its habitat, open seas often far from ports and airfields, and its long-distance migratory behaviour, studying and monitoring its distribution is costly. Currently, many opportunistic sightings (OS) reports are available, which provide a source of potentially useful, low-cost information about the spatio-temporal distribution of this species.