Seasonal distribution of short-tailed shearwaters and their prey in the Bering and Chukchi seas

Nishizawa Bungo; Matsuno Kohei; Labunski Elizabeth A.; Kuletz Kathy J.; Yamaguchi Atsushi; Watanuki Yutaka

Title	en Seasonal distribution of short-tailed shearwaters and their prey in the Bering and Chukchi seas
Creator	en Nishizawa, Bungo en Matsuno, Kohei NRID 1000090712159 en Labunski, Elizabeth A. en Kuletz, Kathy J. en Yamaguchi, Atsushi NRID 1000050344495 en Watanuki, Yutaka NRID 1000040192819
Accessrights	open access
Rights	https://creativecommons.org/licenses/by/3.0/ en Creative Commons Attribution 3.0 Unported
Subject	NDC 660
Description	Abstract en The short-tailed shearwater (Ardenna tenuirostris) is one of the abundant marine top predators in the Pacific; this seabird spends its non-breeding period in the northern North Pacific during May-October and many visit the southern Chukchi Sea in August-September. We examined potential factors affecting this seasonal pattern of distribution by counting short-tailed shearwaters from boats. Their main prey, krill, was sampled by net tows in the southeastern Bering Sea/Aleutian Islands and in the Bering Strait/southern Chukchi Sea. Short-tailed shearwaters were mainly distributed in the southeastern Bering Sea/Aleutian Islands (60 +/- 473 birds km(-2)) in July 2013, and in the Bering Strait/southern Chukchi Sea (19 +/- 91 birds km(-2)) in September 2012. In the Bering Strait/southern Chukchi Sea, krill size was greater in September 2012 (9.6 +/- 5.0 mm in total length) than in July 2013 (1.9 +/- 1.2 mm). Within the Bering Strait/southern Chukchi Sea in September 2012, short-tailed shearwaters occurred more frequently in cells (50 +/- 50 km) where large-sized krill were more abundant. These findings, and information previously collected in other studies, suggest that the seasonal northward movement of short-tailed shearwaters might be associated with the seasonal increase in krill size in the Bering Strait/southern Chukchi Sea. We could not, however, rule out the possibility that large interannual variation in krill abundance might influence the seasonal distribution of shearwaters. This study highlights the importance of krill, which is advected from the Pacific, as an important prey of top predators in the Arctic marine ecosystem.
Publisher	en Copernicus Publications
Date	Issued2017-01-13
Language	eng
Resource Type	journal article
Version Type	VoR
Identifier	HDL http://hdl.handle.net/2115/64945
Relation	isIdenticalTo DOI https://doi.org/10.5194/bg-14-203-2017
Journal	PISSN 1726-4170 en Biogeosciences Volume Number14 Issue Number1 Page Start203 Page End214
File	fulltext Nishizawa.pdf 2.22 MB (application/pdf) Issued2017-01-13
Oaidate	2023-07-26