Can you tell me why transient killer whale pods seek out sea lions/whale
calves and other mammals while resident killer whale pods eat mainly fish?
Thanks for your help!
Both populations maintain social isolation from one another, and also differ
in genetic structure, morphology, behavior, distribution patterns, and
ecology. The 'residents' are fish specialists, while the 'transients' are
primarily mammal hunters.
Basically, the two different populations of killer whales - residents and
transients - have over time, become specialized for feeding on these
particular types of food. It is likely that poulations with dietary
specializations exist wherever sufficiently abundant and reliable prey
resources are available to sustain them year-round. The reason is basically
that the residents happen to occur in the areas where fish, such as chinook
and coho salmon occur. Even though mammals are around 'residents', they do
not eat them (this doesn't mean that the other marine mammals aren't
harrassed or on occasion, killed sometimes). Transients, depending on which
part of the country they live, eat different types of marine mammals and
Just to complicate matters even more, besides residents and transients, a
third population occurs 'offshore'. No one knows the feeding habits of those
Hope this answers your question.
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