Orcinus Orca
Robust, heavy body; bluntly tapered head with no obvious snout;
very tall, straight dorsal fin in males, up to six feet high;
much smaller, sickle-shaped dorsal fin in females; large paddle-shaped
flippers, that can make up to 1/5 of body length in males.
Recognisable black and white markings; white chin and chest,
with an elliptical white patch above each eye; white patches
on sides behind and below dorsal fin; grey 'saddle patch'
directly behind dorsal fin, shape varies from animal to animal.
Up to 50-60 years in males, average lifespan 29.2 years; Up
to 80-90 years in females, average lifespan 50.2 years.
Between 14 and 20 years in males, 14-15 years in females.
17-month gestation period; typically, calves are born every
5 years.
Active and acrobatic at the surface. Breaches, spyhops and
lob-tailing are regularly seen.
Orcas live in large family groups called pods, which can
comprise 3 generations of killer whale families. Pods can
contain up to twenty family members of all ages, mostly females.
Females, unlike in many animal groups, are the matriarchs
of society. Large adult males may dwarf their mothers with
their huge flippers, massive dorsal fins, and robust bodies,
but they will probably stay with their mums for life.
There are two 'types' of Orca; Transients and Residents.
There are differences between the two types in feeding habits,
pod size, even swimming patterns!
Residents: Resident Orcas have their own particular territory
e.g. Vancouver Island in Canada. Their diet is mainly comprised
of fish, but the type of fish depends on the kind living in
the area. For example, the mainstay of North Atlantic Orcas
is the vast amount of herring that live there; in Johnstone
Strait, Canada, the whales live on the salmon that come through
the Strait every year. Pod can contain from eight to twenty
members. Residents tend to vocalise more than transients and
stay underwater for shorter periods of time.
Transients: Transient Orcas have no particular territory,
and tend to be more offshore than residents. Their diet is
more mammal-based, and they eat seals, sea lions, porpoises,
other dolphins and even whales; Orcas have been videoed attacking
a blue whale, the largest animal on earth. Transients are
the Orcas seen hauling themselves onto beaches to catch a
quick sea lion meal! Pod sizes are much smaller, from one
to seven whales, and they vocalise less frequently than residents.
They stay underwater for 5-15 minutes at a time.
Orcas are famous for their complex vocalisations. Recordings
of their squeaks, clicks and other 'babble' has been put onto
many CDs and cassettes. In killer whale 'language', there
are certain components that occur in every Orca pod. But,
there are also some components that are specific to one pod
and only one pod. This 'dialect' is part of what makes it
so hard for us humans to have a clear idea of what Orcas are
saying. In Canada, there is even a radio station 'Orca FM'
that is on air 12 hours a day playing live Orca vocalisations!
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