Seasonal changes in density of the finless porpoise (<i>Neophocaena phocaenoides</i>) around the mouth of Mikawa Bay, Japan

DOI Web Site 2 Citations 27 References
  • Taguchi Mioko
    Laboratory of Fish Culture, Graduate School of Bioresources, Mie University Chair of Marine Bioresource Science, Graduate School of Fisheries Sciences, Hokkaido University
  • Yoshioka Motoi
    Laboratory of Fish Culture, Graduate School of Bioresources, Mie University
  • Kashiwagi Masaaki
    Laboratory of Fish Culture, Graduate School of Bioresources, Mie University

Bibliographic Information

Other Title
  • 三河湾湾口部におけるスナメリの分布密度の季節変化
  • ミカワワン ワンコウブ ニ オケル スナメリ ノ ブンプ ミツド ノ キセツ ヘンカ

Search this article

Abstract

To study seasonal changes in the density of finless porpoises (Neophocaena phocaenoides) around the mouth of Mikawa Bay in Japan, sighting surveys were conducted by the line transect method on board a car ferry in 2002-2004. A total of 7,153 km was surveyed and 780 animals in 224 schools were found along the transects under sighting conditions of Beaufort wind force scale 2 and under. The density of finless porpoises increased from December to May (0.06-2.22 animals/km2) and decreased from June to November (0-0.22 animals/km2). Comparison with previous studies covering the whole area of the bay indicated that the finless porpoise expanded its range outside of the bay during fall. School sizes showed significant daily changes in winter to spring with larger schools formed after 3 p.m. These changes in density and school size suggested that the study area was important for feeding.<br>

Journal

Citations (2)*help

See more

References(27)*help

See more

Keywords

Details 詳細情報について

Report a problem

Back to top