Biogeography of top predators – seabirds and cetaceans – along four latitudinal transects in the Atlantic Ocean


Contact
simon.jungblut [ at ] awi.de

Abstract

The distribution, abundance, and species assemblage of top predators - seabirds and cetaceans - can be correlated to water masses as defined by hydrological parameters. In comparison to other oceans, information about the structuring effects of water masses on top predators in the Atlantic Ocean is limited. The present study aims 1) to provide baseline distributional data of top predators for future comparisons, for instance in the course of climate change, and 2) to test how water masses and seasons affect distributional patterns of seabirds and cetaceans in the temperate and tropical Atlantic. During four trans-equatorial expeditions of the RV Polarstern between 2011 and 2014, at-sea observation data of seabirds, cetaceans and other megafauna were collected. Counts of top predators were generally low in the surveyed regions. Statistical analyses for the eight most abundant seabird species and the pooled number of cetaceans revealed water masses and seasons to account for differences in counts and thus also distribution. In most cases, borders between water masses were not very distinct due to gradual changes in surface water properties. Thus, top predator counts were correlated to water masses but, in contrast to polar waters, not strongly linked to borders between water masses. Additional factors, e.g. distance to locally productive areas (upwelling), competition effects, and seabird associations to prey-accumulating subsurface predators may be similarly important in shaping distributional patterns of top predators in the tropical and temperate Atlantic, but could not be specifically tested for here.



Item Type
Article
Authors
Divisions
Primary Division
Programs
Primary Topic
Peer revision
ISI/Scopus peer-reviewed
Publication Status
Published
Eprint ID
45229
DOI 10.1016/j.dsr2.2017.04.005

Cite as
Jungblut, S. , Nachtsheim, D. A. , Boos, K. and Joiris, C. R. (2017): Biogeography of top predators – seabirds and cetaceans – along four latitudinal transects in the Atlantic Ocean , Deep-Sea Research Part II-Topical Studies in Oceanography, 141 , pp. 59-73 . doi: 10.1016/j.dsr2.2017.04.005


Share


Citation

Research Platforms

Campaigns


Actions
Edit Item Edit Item