SR3’s Dr. Fearnbach and colleagues from NOAA’s Southwest Fisheries Science Center, Tethys Research Institute and ISPRA recently published a paper on the movement patterns of Antarctic killer whales. The paper titled “Skin in the game: Epidermal molt as a driver of long-distance migration in whales” was published in Marine Mammal Science (https://doi.org/10.1111/mms.12661) and presents results from eight years of satellite tag tracking on four ecotypes of killer whales (Types A, B1. B2 and C) in the Southern Ocean, extending upon the previously published research Antarctic killer whales make rapid, round-trip movements to subtropical waters: evidence for physiological maintenance migrations? (https://doi.org/10.1098/rsbl.2011.0875). These papers describe rapid and long-distance movements away from Antarctica by all four ecotypes, hypothesized to facilitate skin regeneration in warmer waters. As such, these “skin molt migrations” are thought to represent an adaptation to allow foraging in productive, but frigid polar waters that are challenging for mammalian physiology.
Dr. Fearnbach and colleagues Dr. John Durban (Southall Environmental Associates) and Jessica Farrer (SR3) are currently en route to Antarctica onboard the M/V National Geographic Explorer to resume annual research monitoring the health of top consumers (humpback and minke whales) and top predators (killer whales) in the rapidly changing ecosystem of the Antarctic Peninsula. This project is supported by the Lindblad Expeditions – National Geographic Conservation Fund.
Photograph of an adult female Type B2 killer whale with her newborn calf in the coastal waters of the Antarctic Peninsula; note the yellow color due to accumulation of planktonic diatoms. This accumulation indicates that skin regeneration is not occurring in frigid Antarctic waters, requiring long-distance movements to warm tropical waters that are thermally advantageous. Photograph by Leigh Hickmott (SR3) collected under NMFS Research Permit 19091 and Antarctic Conservation Act Permit 2017-029.