Multi-scale habitat preference analyses for Azorean blue whales

PLoS One. 2018 Sep 28;13(9):e0201786. doi: 10.1371/journal.pone.0201786. eCollection 2018.

Abstract

Blue whales are sighted every year around the Azores islands, which apparently provide an important seasonal foraging area. In this paper we aim to characterize habitat preferences and analyze the temporal distribution of blue whales around São Miguel Island. To do so, we applied Generalized Additive Models to an opportunistic cetacean occurrence dataset and remotely sensed environmental data on bathymetry, sea surface temperature, chlorophyll concentration and altimetry. We provide a brief description of the oceanography of the area, emphasizing its high spatio-temporal variability. In order to capture this dynamism, we used environmental data with two different spatial resolutions (low and high) and three different temporal resolutions (daily, weekly and monthly), thus accounting for both long-term oceanographic events such as the spring bloom, and shorter-term features such as eddies or fronts. Our results show that blue whales have a well-defined ecological niche around the Azores. They usually cross the archipelago from March to June and habitat suitability is highest in dynamic areas (with high Eddy Kinetic Energy) characterized by convergence or aggregation zones where productivity is enhanced. Multi-scale studies are useful to understand the ecological niche and habitat requirements of highly mobile species that can easily react to short-term changes in the environment.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Balaenoptera / physiology*
  • Ecosystem*
  • Female
  • Male
  • Models, Biological*

Grants and funding

This work was supported by the Applied Physics Department of the Universidad de Vigo (Spain); a predoctoral grant from Consellería de Cultura, Educación e Ordenación Universitaria, Xunta de Galicia [Modalidade B] (PRE/2013/409) for the Marine Science, Technology and Management (DOMAR) PhD Program (www.edu.xunta.gal/); and a grant from LabexMER action for young researchers in 2016 (https://www.labexmer.eu/). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.