Implementation of effective conservation planning relies on a robust
understanding of the spatio-temporal distribution of the target species.
In the marine realm, this is even more challenging for cryptic species
with extreme diving behaviour like the sperm whales. Our study aims at
investigating the movements and predicting suitable habitat maps for this
species in the Mascarene Archipelago in the South-West Indian Ocean. Using
21 satellite tracks of sperm whale and 8 environmental predictors, 14
supervised machine learning algorithms were tested and compared to predict
the whales’ distribution during the wet and dry season, separately.
Fourteen of the whales remained in close proximity to Mauritius while a
migratory pattern was evidenced with a synchronized departure for 8
females that headed towards Rodrigues Island. The best performing
algorithm was the random forest, showing a strong affinity for Sea Surface
Height during the wet season and for bottom temperature during the dry
season. A more dispersed distribution was predicted during the wet season
whereas a more restricted distribution to Mauritius and Reunion waters was
found during the dry season. The results of our study fill a knowledge gap
regarding seasonal movements and habitat affinities of this vulnerable
species, for which IUCN regional assessments are still lacking in the
Indian Ocean. Our findings also confirm the great potential of machine
learning algorithms in conservation planning and provide concrete tools to
support dynamic ocean management.