Documentation of a New Zealand blue whale population based on multiple lines of evidence

Endangered species research

C. Scott Baker^1,3¹  Leigh G. Torres^1²  Todd E. Chandler^1³  Debra Glasgow^7⁴  Rochelle Constantine^3⁵  Michael C. Double^5⁶  Dawn R. Barlow^1⁷  Debbie Steel^1⁸  Nadine Bott^4⁹  Kristin B. Hodge^2^1,10  Peter Gill^6^1,11 

[1] Australian Marine Mammal Centre, Australian Antarctic Division, Kingston, TAS 7050, Australia^5;Bioacoustics Research Program, Cornell Lab of Ornithology, Cornell University, Ithaca, NY 14850, USA^2;Blue Whale Study, Narrawong, VIC 3285, Australia^6;Coastal-Marine Research Group, Institute of Natural and Mathematical Sciences, Massey University, Auckland 0745, New Zealand^10;Department of Life Sciences, Texas A&M University - Corpus Christi, Corpus Christi, TX 78412-5802, USA^8;Marine Mammal Institute, Department of Fisheries and Wildlife, Oregon State University, Newport, OR 97365, USA^1;New Zealand Department of Conservation, Wellington 6143, New Zealand^4;PO Box 98, Paekakariki 5034, New Zealand^7;School of Biological Sciences, University of Auckland, Auckland 1142, New Zealand^3;Southwest Fisheries Science Center NMFS/NOAA, La Jolla, CA 92037, USA^9

关键词: Blue whale;    New Zealand;    Photo-identification;    Abundance;    Acoustics;    Genetics;    Population connectivity;    Conservation;   

DOI  :  10.3354/esr00891

学科分类：动物科学

来源: Inter-Research

【 摘 要 】

Species conservation depends on robust population assessment. Data on population abundance, distribution, and connectivity are critical for effective management, especially as baseline information for newly documented populations. We describe a pygmy blue whale Balaenoptera musculus brevicauda population in New Zealand waters with year-round presence that overlaps with industrial activities. This population was investigated using a multidisciplinary approach, including analysis of survey data, sighting records, acoustic data, identification photographs, and genetic samples. Blue whales were reported during every month of the year in the New Zealand Exclusive Economic Zone, with reports concentrated in the South Taranaki Bight (STB) region, where foraging behavior was frequently observed. Five hydrophones in the STB recorded the New Zealand blue whale call type on 99.7% of recording days (January to December 2016). A total of 151 individuals were photo-identified between 2004 and 2017. Nine individuals were resighted across multiple years. No matches were made to individuals identified in Australian or Antarctic waters. Mitochondrial DNA haplotype frequencies differed significantly between New Zealand (n = 53 individuals) and all other Southern Hemisphere blue whale populations, and haplotype diversity was significantly lower than all other populations. These results suggest a high degree of isolation of this New Zealand population. Using a closed capture-recapture population model, our conservative abundance estimate of blue whales in New Zealand is 718 (SD = 433, 95% CI = 279-1926). Our results fill critical knowledge gaps to improve management of blue whale populations in New Zealand and surrounding regions.

【 授权许可】

Unknown