Ontogenetic changes in at-sea distributions of immature short-tailed albatrosses Phoebastria albatrus

The ability of juveniles of wide-ranging species to locate distant foraging regions can rely on innate or learned information. Reliance on innate cues could be problematic when conservation actions facilitate reintroduction. In the North Pacific, the short-tailed albatross Phoebastria albatrus is re...

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Bibliographic Details
Published in:Endangered Species Research
Main Authors: Orben, RA, O’Connor, AJ, Suryan, RM, Ozaki, K, Sato, F, Deguchi, T
Format: Article in Journal/Newspaper
Language:English
Published: Inter-Research 2018
Subjects:
Online Access:https://doi.org/10.3354/esr00864
https://doaj.org/article/4f830aa41669402aaf18618818f66dd7
Description
Summary:The ability of juveniles of wide-ranging species to locate distant foraging regions can rely on innate or learned information. Reliance on innate cues could be problematic when conservation actions facilitate reintroduction. In the North Pacific, the short-tailed albatross Phoebastria albatrus is recovering from extensive harvesting, and has recently benefited from translocation efforts. Yet little is known about how naïve juveniles disperse or about individual distributions of immature short-tailed albatrosses. The primary goals of this study were to quantify the ontogeny of movement patterns and spatial distributions and compare these between naturally reared and translocated short-tailed albatrosses. We tracked 51 albatrosses for up to 5 years post-fledging: naturally reared chicks from their natal colony on Torishima, Japan, and chicks that were translocated 350 km to the southeast to Mukojima, Japan. Initial, more northerly dispersal of translocated fledglings suggests the ability to adjust to a new departure location. Fledglings’ departure paths differed from previously tracked adults departing Torishima, yet like adults, the majority of fledglings (81%) reached the Bering Sea that first summer, further supporting large-scale innate orientation abilities. Juveniles showed strong seasonal changes in distributions, traveling more in winter and occupying regions not typically used by adults (e.g. California Current, Sea of Okhotsk). As they aged, juveniles began to exhibit habitat fidelity to shelf-break regions, as anticipated from prior studies, yet continued to explore new regions with low levels of spatial fidelity. Juvenile short-tailed albatrosses explored almost the entire species range, highlighting the impressive capacity of individuals to transverse the North Pacific.