Killer whales are one of the most geographically widespread species in the world, occurring in all oceans and all latitudes. Through observational work it has been widely accepted that three distinct ecotypes exist: "resident", "offshore", and "transient", based on distribution, behavior, morphology, and diet. There are some weird things going on with Antarctic killer whales, but we won't go into that here. Recent evidence of both mitochondrial and nuclear DNA suggests that these three ecotypes are in fact genetically distinct. For each ecotype, based of photographic identification of individuals, animals are bound within discrete sub-populations or "stocks". In Alaska, transient killer whales, the type that hunt marine mammals, appear to be segregated into two slightly overlapping ranges, the Gulf of Alaska and the Aleutian Islands/Bering Sea. Again using photographic identification and line transect estimates, roughly 450 individuals occur within in Aleutian Island/Bering Sea stock. Over the past month on St Paul, we have spotted small pods of transient killer whales on six separate occasions. Yesterday this pod of five, consisting of one male, three female types, and a calf, approached close enough to shore to snap a few decent photographs from the cliffs. With half a million fur seals arriving for the breeding season, it's not surprising these killer whales are lingering offshore.
Canon EOS 60D, Canon EF 70-200mm f/4L USM + 1.4x, ISO-800 f/5.6 @ 1/5000 sec.
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