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Non-Equal Spatial Distribution

While habitats of terrestrial animals are in principal two-dimensional and relatively stable, marine habitats are three-dimensional and continuously changing. This forces cetaceans to be highly mobile and capable of travelling long distances. This especially applies for rorqual whales most of which undertake annual migrations between their breeding and feeding ground.

If an animal spends more time in one habitat type than expected by chance alone, this is defined as preference for that particular habitat. Site fidelity is defined as the tendency of an animal to remain in an area over an extended period, or to return to an area previously occupied.

Concentrating in zones of upwellings

Within the study area, topographic and oceanographic features create different small-scale habitats. The occurrence, density and depth of prey constantly shift in space and time but are generally concentrated in areas of strong currents, upwellings, and rip tides. Minke whales in general and individuals specifically constantly adjust to the predominant conditions at any given time use differently on a spatial, temporal and behavioural scale. Long-term studies allow the identification and characterisation of feeding habitats and responses of whales to possible changes thereof over time.

Minke whales also show high intra- and inter-annual variability in spatial and temporal distribution over many years. Such heterogeneity in habitat use and distribution must be taken into account when estimating abundance and when managing populations or protected areas. Long-term studies allow the identification and characterisation of feeding habitats and responses of whales to possible changes thereof over time.