Dear all, I am pleased to announce the recent publication of our paper in Ecology and Evolution::
Herr H, Kelly N, Dorschel B, Huntemann M, Kock K-H, Lehnert LS, Siebert U, Viquerat S, Williams R, Scheidat M (2019) Aerial surveys for Antarctic minke whales (Balaenoptera bonaerensis) reveal sea ice dependent distribution patterns. Ecol Evol. 2019;00:1–19. https://doi.org/10.1002/ece3.5149 Abstract This study investigates the distribution of Antarctic minke whales (AMW) in relation to sea ice concentration and variations therein. Information on AMW densities in the sea ice-covered parts of the Southern Ocean is required to contextualize abundance estimates obtained from circumpolar shipboard surveys in open waters, suggesting a 30% decline in AMW abundance. Conventional line-transect shipboard surveys for density estimation are impossible in ice-covered regions, therefore we used ice- breaker-supported helicopter surveys to obtain information on AMW densities along gradients of 0%–100% of ice concentration. We conducted five helicopter surveys in the Southern Ocean, between 2006 and 2013. Distance sampling data, satellite-de- rived sea-ice data, and bathymetric parameters were used in generalized additive models (GAMs) to produce predictions on how the density of AMWs varied over space and time, and with environmental covariates. Ice concentration, distance to the ice edge and distance from the shelf break were found to describe the distribution of AMWs. Highest densities were predicted at the ice edge and through to medium ice concentrations. Medium densities were found up to 500 km into the ice edge in all concentrations of ice. Very low numbers of AMWs were found in the ice-free waters of the West Antarctic Peninsula (WAP). A consistent relationship between AMW dis- tribution and sea ice concentration weakens the support for the hypothesis that vary- ing numbers of AMWs in ice-covered waters were responsible for observed changes in estimated abundance. The potential decline in AMW abundance stresses the need for conservation measures and further studies into the AMW population status. Very low numbers of AMWs recorded in the ice-free waters along the WAP support the hypothesis that this species is strongly dependent on sea ice and that forecasted sea ice changes have the potential of heavily impacting AMWs. The open access paper is available at: https://onlinelibrary.wiley.com/doi/epdf/10.1002/ece3.5149 <https://onlinelibrary.wiley.com/doi/epdf/10.1002/ece3.5149> Please do not hesitate to contact me if you have any questions. Kind regards Helena -- Dr. Helena Herr Centrum für Naturkunde – CeNak – Center of Natural History Martin-Luther-King-Platz 3 / Room 243b 20146 Hamburg - Germany phone +49 (0) 40 42838 1560 email: [email protected] www.cenak.uni-hamburg.de <http://www.cenak.uni-hamburg.de/> Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research Section Polar Biological Oceanography AG Ecophysiology of Pelagic Key Species Am Handelshafen 12 / Building E, Room 2390 27570 Bremerhaven - Germany phone: +49 (0) 471 4831 2360 email: [email protected]
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