The research vessel, Yushin-Maru No.3arrived in Shiogama Harbour on 9 September 2013 after completing the fourth annual IWC-POWER (International Whaling Commission - Pacific Ocean Whale and Ecosystem Research) survey. This year’s survey began on 12 July 2013 when the ship departed Shiogama to survey the whales of the Eastern North Pacific.
The IWC-POWER survey is a successor to the IWC/IDCR-SOWER cruises, a 32-year study of the whale populations of the Southern Ocean, directed by the IWC's Scientific Committee. This year’s IWC-POWER cruise surveyed a stratum to the south and east of the cruises conducted in 2010, 2011 and 2012.
The research vessel was provided to the IWC by the Government of Japan and the research was conducted by a team of four scientists of three nationalities: Koji Matsuoka (cruise leader, Japan), Hyun-Woo Kim (Republic of Korea), Sergio Martinez-Aguilar (Mexico) with Saeko Kumagai (Japan) completing the research team. This year’s research area was north of 30°N, south of 40°N, between longitudes 160°W and 135°W (High Sea).
The IWC-POWER research programme is unanimously supported by the member nations of the IWC. The programme did not involve the capture or removal of animals.
The main objectives for the 2013 IWC-POWER cruise were to:
(1) provide information for the proposed future in-depth assessment of sei and other whales in terms of abundance, distribution and stock structure;
(2) provide information relevant to IWC’s Implementation Reviews of whales (e.g. common minke whales) in terms of both abundance and stock structure;
(3) provide baseline information on distribution and abundance for a poorly known area for several large whale species/populations, including species which were known to have been depleted in the past, but whose status is unclear at present;
(4) provide photo-identification data and biopsy samples to study distribution and stock structure for large whale species/populations, especially those that were known to have been depleted in the past but whose status is unclear;
(5) provide essential information for the intersessional IWC workshop that is tasked with developing a long-term international research programme in the North Pacific.
Whale sightings included 3 fin whales, 4 sei whales, 64 Bryde’s whales and 99 sperm whales during the effective searching distances (4,314 n.miles). Photo-identification data were collected for the 3 fin whales, 2 sei whales and 6 Bryde’s whales. Skin samples for genetic analyses were collected from 1 fin whale, 1 sei whale and 6 Bryde’s whales.
Line transect sightings data, photo-identification and biopsy data collected during this year’s cruise will allow researchers to begin to assess a photo-identification data and biopsy samples for abundance estimation, and to study distribution, movements and stock structure of whales in the North Pacific.
Further details of this cruise will be presented at the IWC scientific committee meeting to be held in May/June 2014.