Results of the first cruise of the New Scientific Whale Research Program in the western North Pacific (NEWREP-NP) in the 2017 summer season –Off shore component
Kenji Konishi, Tatsuya Isoda, Kazuhiro Nakai, Hiroyuki Oikawa, Jun Kanbayashi, Mayuka Uchida, Masaomi Tsunekawa, Yuu Ueda, Takashi Kominami, Shinya Kawabe, Hiroshi Eguchi and Tsutomu Tamura
International Whaling Commission
This paper reports the results of the first biological survey of sei and common minke whales under the New Scientific Whale Research Program in the western North Pacific (NEWREP-NP)-offshore component. The survey was conducted in part of sub-Areas 7(7WR and 7E), 8 and 9 (-170°E), north of 35°N from June to September 2017. Two sighting sampling vessels (SSVs) and one research base vessel were engaged in the survey for 100 days. A total of 56 sightings (involving 61 individuals) of common minke whale and 320 sightings (involving 407 individuals) of sei whales were made during 5,307 n.miles of searching distance. A total of 43 common minke whales and 134 sei whales were sampled as originally planned. Sei whales were all sampled along the predetermined tracklines in the Normal survey which was designed in a systematic way, and common minke whales were sampled along both the Normal survey and the Special survey track lines which were designed for areas where the density of common minke whales was expected to be high. Overall searching effort was optimized and the research area was covered adequately. Biological samples and data required for the two primary objectives of NEWREP-NP were obtained from each whale sampled. In particular earplugs for age determination and reproductive organs for sexual maturity determination were collected for all individuals. Preliminary biological analyses were conducted and results are presented in this paper. Sardine and mackerels were major prey species for both sei and common minke whales. Eight blue and one humpback were photo-identified, and biopsy samples were collected from five blue, 17 sei and one humpback whales. Satellite tags were deployed on 15 sei whales and the locations were obtained from eight individuals. The samples and data collected in this survey will be available for interested national and international scientists under the guidelines for research collaboration in NEWREP-NP.