Among humans, it is easy to see
differences in behavior between families, communities,
and countries. We call this culture. But humans are not
the only species with culture. Although not quite as
visible or extreme, Orcas are one species that can be
said to have culture as well.
In the Pacific Northwest, there
are three known ecotypes of Killer Whale: Residents,
Transients, and Offshores. Despite the fact that these
are all members of the same species, each of these
varieties live very different lifestyles.
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Resident Orcas typically live in large
stable social groups. These pods usually
consist of a matriarch, or dominant female,
and her young. Often, the matriarch will
travel with other related females, such as
sisters, and their offspring. As offspring
become mature, they tend to remain with
their mothers as long as she is alive. Since
residents eat mostly fish and salmon, they
are thought to benefit from this type of
social structure when foraging. |
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Transient Orcas
tend to travel in smaller groups that
can vary considerably over time.
Transients are hunters of mammals of all
sizes. It is suspected that their group
size varies with their needs for each
other when foraging for seals, sea
lions, porpoises, or larger whales.
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Less is known about Offshore Orcas
since they live further out at sea and are less
accessible to scientific observers. They have been seen
in fairly large groups, and it is thought that they eat
fish and have a lifestyle similar to resident whales.
These different killer whale
groupings have a preferred diet and different life style
despite overlapping ranges and the identical foraging
opportunities. Such differences can be viewed as
cultural.
There are many other examples from
around the world. In the icy waters off Norway, Orcas
use a different hunting technique. Working as a group,
they slowly herd huge schools of herring into tight
balls of fish. The whales then smack these balls with
their extremely powerful tails, stunning the fish. As
their prey lie motionless in the water, the Orcas circle
back around to eat them.
In Patagonia, South America, Orcas
specialize in hunting sea lions. Rookeries, where sea
lion pups are born, are the favored hunting grounds of
these whales. When pups are first weaned, they often
venture too close to the water’s edge where Orcas rush
onto shore to grab them.
And "cultural" differences do not
just pertain to diet. Between Antarctica and South
Africa are the Crozet Islands. Orcas here are known to
visit kelp beds several times a day to swim through the
thick gardens of seaweed. It seems that the whales enjoy
the sensations so much that they may do this several
times a day. Orcas elsewhere have not been seen to do
this. By contrast Resident whales in British Columbia
have been observed rubbing themselves on shallow
pebblely beaches like the one below. Orcas elsewhere
have not been observed to do this.

Orca "rubbing beach" in British
Columbia