Arctic Research Directory

ID-126 :   Seasonal distribution of short-tailed shearwaters and their prey in the Bering and Chukchi seas

Type

FIELDWORK

Research/Observation Title

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

Science Summary (common)

The marine ecosystems of the Bering Sea and adjacent Chukchi Sea are experiencing rapid changes due to reductions in sea-ice. In the Bering Sea and Chukchi Sea shelf regions, seabirds, as homoeothermic top predators, play a significant role in the trophic energy flow. As mobile predators that can respond quickly to shifts in the distribution of prey (i.e., by switching foraging areas or prey species), changes in their distribution can potentially serve as indicators of fluctuations of trophic relationships. Thus, knowledge of recent changes in the distributions of top predators and their prey should provide useful information about large-scale ecosystem changes in these regions with seasonal sea-ice. Short-tailed shearwaters Puffinus tenuirostris visit this region between the summer and fall during non-breeding season, and show highest biomass among seabirds distributed in the region during the periods. The main objective of this study is to understand the links between seasonal distribution of short-tailed shearwaters, their prey (i.e., krill) and marine environments.
- Individual Project Information 1/1 Research/Observation Period 2016-08-27 〜 2016-09-27

Discipline(s)

Biology, Oceanography

Personnel

RollContact PersonNameBungo NishizawaAffiliationGraduate School of Fisheries SciencesCountryJapanEmailnishizawa@salmon.fish.hokudai.ac.jp
RollContact PersonNameYutaka WatanukiAffiliationHokkaido UniversityCountryJapanEmailywata@fish.hokudai.ac.jp

Research/Observation Methods

As the ship cruised during the daytime, one observer recorded numbers and behaviors (flying, sitting on water or foraging) of seabirds at every 1-minute detected within a 300 m arc (from the bow to 90°to port or to starboard) of the side of the vessel that afforded the best observation conditions (i.e., least sun glare). The Observer confirmed species identification and counted the number of seabirds using a 8 × binocular (Victory FL 8 x 56, ZEISS, Germany) from the ship’s bridge, approximately 16 m eye-height above the sea surface. Ship-following birds were recorded when they first entered the survey range, and were ignored thereafter.

Research/Observation Period

2016-08-27 〜 2016-09-27

Research/Observation Area

N: 73.860556, S: 51.258333, W: 168.626389 E: -152.018611,
Data Registration
15:09 on Thu January 12, 2017
Last Update
10:46 on Wed July 18, 2018