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Strong Site-Fidelity of Individuals

Over 220 individuals have been identified since the late 1970s, 70% of which were seen in more than one year. In 1990 Dorsey et al. first reported small-scale site fidelity of minke whales off the west coast of North America. In addition to spatial segregation, individual specialisations on foraging strategies were also observed.

Preferred habitats

In this study we present examples of strong individual preferences for specific feeding areas in the Saguenay-St. Lawrence Marine Park. These are (1) the slopes of the Laurentian Channel (LC) and (2) the fjord and mouth of the Saguenay River, sites that differ considerably in respect to topography, currents, riptide formation, water turbidity, boat traffic and noise.

The results show striking differences in individual habitat use. Apparently most individuals that regularly forage within the study area exhibit a certain degree of small-scale site fidelity.

Specialisation might increase feeding success

Spatial fidelity can lead to individual specialisation on foraging techniques adapted to prevailing environmental conditions, or indeed be the result of such specialisation. Individually characteristic foraging behaviour has been described for many whales that frequently feed in the Saguenay Region. Whereas the reported acquisition of new feeding techniques supposedly increases foraging efficiency in a specific environment, the question arises whether such specialisation may increase sensitivity towards environmental changes.

Long-term monitoring to discover potential changes

By studying individual differences and changes of habitat use in relation to environmental parameters, we hope to learn more about the adaptability of minke whale behaviour. For example, a general shift of sightings into the Saguenay Region has been observed from 2000 to 2005.  Finally, we believe such heterogeneity of habitat use must be taken into account when estimating abundance and when managing populations or protected areas.

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