title: Movement patterns for a critically endangered species, the leatherback turtle (Dermochelys coriacea), linked to foraging success and population status.
abstract: Foraging success for pelagic vertebrates may be revealed by horizontal and vertical movement patterns. We show markedly different patterns for leatherback turtles in the North Atlantic versus Eastern Pacific, which feed on gelatinous zooplankton that are only occasionally found in high densities. In the Atlantic, travel speed was characterized by two modes, indicative of high foraging success at low speeds (<15 km d(-1)) and transit at high speeds (20-45 km d(-1)). Only a single mode was evident in the Pacific, which occurred at speeds of 21 km d(-1) indicative of transit. The mean dive depth was more variable in relation to latitude but closer to the mean annual depth of the thermocline and nutricline for North Atlantic than Eastern Pacific turtles. The most parsimonious explanation for these findings is that Eastern Pacific turtles rarely achieve high foraging success. This is the first support for foraging behaviour differences between populations of this critically endangered species and suggests that longer periods searching for prey may be hindering population recovery in the Pacific while aiding population maintenance in the Atlantic.
authors.affiliation: Chesapeake Biological Laboratory, University of Maryland Center for Environmental Science, Solomons, Maryland, United States of America. hbailey@umces.edu
authors.forename: Helen
authors.initials: H
authors.lastname: Bailey
authors.forename: Sabrina
authors.initials: S
authors.lastname: Fossette
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Bograd
authors.forename: George L
authors.initials: GL
authors.lastname: Shillinger
authors.forename: Alan M
authors.initials: AM
authors.lastname: Swithenbank
authors.forename: Jean-Yves
authors.initials: JY
authors.lastname: Georges
authors.forename: Philippe
authors.initials: P
authors.lastname: Gaspar
authors.forename: K H Patrik
authors.initials: KH
authors.lastname: Strömberg
authors.forename: Frank V
authors.initials: FV
authors.lastname: Paladino
authors.forename: James R
authors.initials: JR
authors.lastname: Spotila
authors.forename: Barbara A
authors.initials: BA
authors.lastname: Block
authors.forename: Graeme C
authors.initials: GC
authors.lastname: Hays
mesh_terms: D000818:Animals; D001522:Behavior, Animal; D009068:Movement; D011157:Population Dynamics; D014426:Turtles / Q000502:physiology*