On January 15, 2009, three scientists from the SWFSC encountered a pod of eight Killer Whales off Del Mar, CA. Two of these whales appear to match known animals. The two known animals were sighted during ORCAWALE 2008 off the U.S./Mexico border. The pod seen off Del Mar this January was hunting common dolphins, which indicates that they were "Transient" type Killer Whales. These whales are ecologically and genetically distinct from the fish-eating "Resident" Killer Whales, which stick together in tightly bonded matrilineal pods of up to 50 animals. Transient whales are known to leave their natal groups as they mature, and pods tend to be very small, usually three whales, but these small pods will combine for brief periods to hunt, socialize, and breed. (Baird & Whitehead, 2000) There were two adult males in the group seen here in January, which may indicate the combination of two pods. There were also two calves in the group.
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Baird, Robin and Hal Whitehead. 2000. Social organization of mammal-eating killer whales: group stability and dispersal patterns. Can. J. Zool. 78:2096-2105.