title: Combining Methods to Describe Important Marine Habitats for Top Predators: Application to Identify Biological Hotspots in Tropical Waters.
abstract: In tropical waters resources are usually scarce and patchy, and predatory species generally show specific adaptations for foraging. Tropical seabirds often forage in association with sub-surface predators that create feeding opportunities by bringing prey close to the surface, and the birds often aggregate in large multispecific flocks. Here we hypothesize that frigatebirds, a tropical seabird adapted to foraging with low energetic costs, could be a good predictor of the distribution of their associated predatory species, including other seabirds (e.g. boobies, terns) and subsurface predators (e.g., dolphins, tunas). To test this hypothesis, we compared distribution patterns of marine predators in the Mozambique Channel based on a long-term dataset of both vessel- and aerial surveys, as well as tracking data of frigatebirds. By developing species distribution models (SDMs), we identified key marine areas for tropical predators in relation to contemporaneous oceanographic features to investigate multi-species spatial overlap areas and identify predator hotspots in the Mozambique Channel. SDMs reasonably matched observed patterns and both static (e.g. bathymetry) and dynamic (e.g. Chlorophyll a concentration and sea surface temperature) factors were important explaining predator distribution patterns. We found that the distribution of frigatebirds included the distributions of the associated species. The central part of the channel appeared to be the best habitat for the four groups of species considered in this study (frigatebirds, brown terns, boobies and sub-surface predators).
authors.affiliation: Centre d'Études Biologiques de Chizé, Station d'Ecologie de Chizé-La Rochelle UMR 7372, Centre National de la Recherche Scientifique, 79360, Villiers en Bois, France.
authors.forename: Laurie
authors.initials: L
authors.lastname: Thiers
authors.affiliation: Instituto Español de Oceanografía, CO Xixón, Camín de l'Arbeyal s/n, 33212, Xixón, Spain.
authors.forename: Maite
authors.initials: M
authors.lastname: Louzao
authors.affiliation: Centre d'Études Biologiques de Chizé, Station d'Ecologie de Chizé-La Rochelle UMR 7372, Centre National de la Recherche Scientifique, 79360, Villiers en Bois, France; Observatoire PELAGIS, CNRS, Université de La Rochelle UMS 3462, 5 allée de l'Océan, 17000, La Rochelle, France.
authors.forename: Vincent
authors.initials: V
authors.lastname: Ridoux
authors.affiliation: Université de la Réunion, Laboratoire ECOMAR (FRE 3560 CNRS), Avenue René Cassin, CS 92003 97744, Saint Denis Cedex 9, Ile de la Réunion, France.
authors.forename: Matthieu
authors.initials: M
authors.lastname: Le Corre
authors.affiliation: Université de la Réunion, Laboratoire ECOMAR (FRE 3560 CNRS), Avenue René Cassin, CS 92003 97744, Saint Denis Cedex 9, Ile de la Réunion, France.
authors.forename: Sébastien
authors.initials: S
authors.lastname: Jaquemet
authors.affiliation: Centre d'Études Biologiques de Chizé, Station d'Ecologie de Chizé-La Rochelle UMR 7372, Centre National de la Recherche Scientifique, 79360, Villiers en Bois, France.
authors.forename: Henri
authors.initials: H
authors.lastname: Weimerskirch
mesh_terms: D000818:Animals; D059001:Aquatic Organisms / Q000502:physiology; D044822:Biodiversity; D046091:Charadriiformes / Q000502:physiology; D017753:Ecosystem; D005260:Female; D020387:Food Chain; D008297:Male; D008962:Models, Theoretical; D009792:Oceans and Seas; D011156:Population Density; D014329:Tropical Climate