Killer whales are instantly recognizable and live in all the world’s oceans, but relatively little is known about their habits in the wild, especially in remote locations such as Antarctica. Scientists Dr. Bob Pitman and Dr. John Durban have been supported by the Lindblad Expeditions-National Geographic (LEX-NG) Fund since 2011, to facilitate their ongoing killer whale research in Antarctica.
Killer whales are the top predators in the Antarctic marine environment and a deeper understanding of their ecology provides key information on the function of the earth’s most rapidly changing ecosystem. Pitman and Durban are deploying small satellite tags to track killer whale movements and migration, to identify key foraging habitats and assess the impact of their predation. Their research has revealed the deepest dives recorded by any of the world’s killer whales (>2000ft) and documented a remarkable “maintenance migration” of Antarctic killer whales to the edge of the tropics and back (>5000 mile round trip), presumably to recover from the demands of foraging in the freezing Antarctic waters. Their research is not all high-tech, however: they use photographs to recognize individual whales from natural markings and estimate abundance and population trends, and often use photographs contributed by guests and naturalists on board the National Geographic Explorer. In addition, they sometimes collect tiny skin biopsy samples from individual whales; DNA analysis of these will help determine how many species of killer whales there currently are in Antarctica waters, which may be as many as 4 or 5.