Results of the NEWREP-A dedicated sighting survey during the 2017/18 austral summer season
Toshihiro Mogoe, Futoshi Yamaguchi, Shinya Kawabe, Taiki Katsumata, Hidenori Kasai, Yasuaki Sasaki, Takeharu Bando and Koji Matsuoka
International Whaling Commission
This paper reports the results of the dedicated whale sighting survey using two vessels (SVs) in the Antarctic Areas V-E (south of 60°S, 165°E–170°W including the Ross Sea) and VI-W (170°W–145°W) under the NEWREP-A in the 2017/18 austral summer season. The SVs conducted the survey under two survey modes (Normal Passing mode: NSP and an Independent Observer mode: IO) based on IWC IDCR/SOWER survey procedures from 10 December 2017 to 20 February 2018. The total searching distance in the research area was 5,196.6 n.miles (9,624.1km), including 2,441.2 n.miles covered in NSP and 2,755.4 n.miles in IO mode. The survey coverage was 61% in the northern stratum and 91% in the southern stratum. A total of five baleen whale species, blue (13 schools/23 individuals), fin (66/106), sei (2/2), Antarctic minke (329/743) and humpback (151/234) whales, and at least three toothed whale species including, sperm (14/14), southern bottlenose (1/2) and killer (42/989) whales were sighted by primary sightings in the research area. Blue whales were found mainly in the western part of the research area. Fin whales were widely distributed in the western sector of Area VI. Antarctic minke whales were the most frequently sighted large whale species. They were widely distributed throughout the research area. Humpback whales were mainly encountered in the western sector of Area VI and eastern part of Area V. Estimated Angle and Distance experiments were conducted in the research area. Routine photo-ID and biopsy sampling on large whales were also conducted. A total of 64 photos were obtained from 12 blue, 8 humpback and 44 killer whales. A total of eight biopsy samples (skin and blubber) was also collected from four blue, one fin and three humpback whales using the Larsen biopsy system. A total of seven marine debris was observed. The sighting data were validated and have already been submitted to the IWC Secretariat. During this survey, feasibility studies on telemetry and biopsy sampling of Antarctic minke whales were completed, and the results are presented in this paper. Krill and oceanographic surveys were also conducted along the track lines designed for sighting. The results are reported separately.