Polar Biology

, Volume 35, Issue 2, pp 281–290

Modeling the relationship of Antarctic minke whales to major ocean boundaries

Authors

    • H.T. Harvey and Associates
  • Dennis Jongsomjit
    • PRBO Conservation Science
  • Grant Ballard
    • PRBO Conservation Science
  • Deborah Thiele
    • Fenner School of Environment and SocietyThe Australian National University
  • William R. Fraser
    • Polar Oceans Research Group
  • Cynthia T. Tynan
    • Associated Scientists at Woods Hole, Inc.
Original Paper

DOI: 10.1007/s00300-011-1075-1

Cite this article as:
Ainley, D.G., Jongsomjit, D., Ballard, G. et al. Polar Biol (2012) 35: 281. doi:10.1007/s00300-011-1075-1

Abstract

The population size of Antarctic minke whales Balaenoptera bonaerensis has been changing simultaneously with profound changes in the physics, i.e., mesopredator habitat features, of the Southern Ocean. Although the two trends may not be related, distinguishing among the factors responsible requires a better understanding of minke whale habitat preferences. For the first time at a large geographic scale, i.e., between 140° E and 35° W, we use data not constrained by vessels needing to avoid sea ice to model the habitat affinities of this pagophilic mesopredator. Using Maxent, we modeled minke whale proximity to the Antarctic Shelf Break Front (ASBF) and the southern boundary of Antarctic Circumpolar Current (sbACC), as well as association with sea ice, given that global climate change is altering the positions or intensity of these features. We also included water depth and chlorophyll (proxy for productivity) as variables. Minke whale presence data were gathered using strip and line census on 55 cruises on board icebreakers during late spring and summer, 1976–2005. The most important variable was distance to ASBF, followed by water depth and sea-ice concentration. That is, found principally in waters south of the sbACC during summer, minke whales were most abundant near the outer edge of the continental shelf (shallow depth), including areas heavily covered by sea ice. We propose that as the sbACC moves south and sea ice disappears, as projected by global climate models, minke whale habitat will shrink, and likely intra- and inter-specific competition will increase.

Keywords

Antarctic circumpolar currentAntarctic minke whaleAntarctic shelf break frontClimate changeSea iceSouthern Ocean

Supplementary material

300_2011_1075_MOESM1_ESM.pdf (1.2 mb)
Supplementary material 1 (PDF 1271 kb )

Copyright information

© Springer-Verlag 2011