Get access

Genetic and family structure in a group of 165 common bottlenose dolphins caught off the Japanese coast

Authors

  • Yuki F. Kita,

    1. Department of Molecular Life Science, Division of Basic Medical Science and Molecular Medicine, Tokai University School of Medicine, Isehara, Kanagawa 259–1143, Japan
    Search for more papers by this author
  • Kazuyoshi Hosomichi,

    1. Department of Molecular Life Science, Division of Basic Medical Science and Molecular Medicine, Tokai University School of Medicine, Isehara, Kanagawa 259–1143, Japan
    Search for more papers by this author
  • Shingo Suzuki,

    1. Department of Molecular Life Science, Division of Basic Medical Science and Molecular Medicine, Tokai University School of Medicine, Isehara, Kanagawa 259–1143, Japan
    Search for more papers by this author
  • Hidetoshi Inoko,

    1. Department of Molecular Life Science, Division of Basic Medical Science and Molecular Medicine, Tokai University School of Medicine, Isehara, Kanagawa 259–1143, Japan
    Search for more papers by this author
  • Takashi Shiina,

    Corresponding author
    1. Department of Molecular Life Science, Division of Basic Medical Science and Molecular Medicine, Tokai University School of Medicine, Isehara, Kanagawa 259–1143, Japan
    Search for more papers by this author
  • Mai Watanabe,

    1. Department of Marine Biology, School of Marine Science and Technology, Tokai University, Shimizu, Shizuoka 424–8610, Japan
    Search for more papers by this author
  • Ayumi Tanaka,

    1. Department of Marine Biology, School of Marine Science and Technology, Tokai University, Shimizu, Shizuoka 424–8610, Japan
    Search for more papers by this author
  • Taku Horie,

    1. Department of Marine Biology, School of Marine Science and Technology, Tokai University, Shimizu, Shizuoka 424–8610, Japan
    Search for more papers by this author
  • Hiroshi Ohizumi,

    1. Department of Marine Biology, School of Marine Science and Technology, Tokai University, Shimizu, Shizuoka 424–8610, Japan
    Search for more papers by this author
  • Sho Tanaka,

    1. Department of Marine Biology, School of Marine Science and Technology, Tokai University, Shimizu, Shizuoka 424–8610, Japan
    Search for more papers by this author
  • Toshihide Iwasaki,

    1. Cetacean Resources Group, National Research Institute of Far Seas Fisheries, Fisheries Research Agency, Yokohama, Kanagawa 236–8648, Japan
    Search for more papers by this author
  • Masao Ota,

    1. Department of Legal Medicine, Shinshu University School of Medicine, Matsumoto, Nagano 390–8621, Japan
    Search for more papers by this author
  • Jerzy K. Kulski

    1. Centre for Forensic Science, The University of Western Australia, Nedlands, Western Australia, 6008 Australia
    Search for more papers by this author

(e-mail: tshiina@is.icc.u-tokai.ac.jp).

Abstract

The biological and genetic structure of common bottlenose dolphins (Tursiops truncatus) that migrate seasonally near Japan remains largely unknown. We investigated the genetic and family structure in a group of 165 common bottlenose dolphins caught off the coast of Japan using mitochondrial DNA (mtDNA) and 20 microsatellite DNA markers. Phylogenetic analysis of the mtDNA control region sequences suggested that the dolphins were related more closely to oceanic types from Chinese waters than other geographic regions. The information on sex, sexual maturation and age together with the genetic markers revealed a strong likelihood for 37 familial relationships related mostly to maternity and an under-representation of juvenile female offspring. The maternal dolphins had a similar offspring-birth interval as the coastal types from North Atlantic Ocean, but a slightly younger first-progeny age. The sex bias in the captured group was particularly marked towards an over-representation of males among the young and immature dolphins, whereas the mature adults had an equal number of males and females. These results should be useful for future comparative biological, genetic and evolutionary investigations of bottlenose dolphins from the North Pacific Ocean with those from other regions.

Ancillary