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Lions
Sea
lions basking in the islands of Haida Gwaii
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There are two
species of sea lions that occur in British Columbia waters. The two
may be found together, but they are here for different reasons.
Sea lions,
unlike the ubiquitous Harbour Seal of the coast, are able to move
about on land using their four flippers. They are further distinguished
by their longer necks and external ears. Sea lions gather at "haul-outs",
where the two species loaf side-by-side.
They are sometimes
seen on the rocks beside the ferry route through Active Pass, and
at Race Rocks near Victoria, among many other suitable rocky islets.
From December through April, sea lions converge on the east side
of Vancouver Island to feed on herring that are returning to spawn.
The log booms at the pulp mill at Harmac has been a good spot to
see both species, and further north, off French Creek, the herring
spawn can produce a wildlife spectacle of epic proportions.
Both species of sea lions may be preyed on by the transient race
of Killer Whales, which almost exclusively eat marine mammals.
Steller's
Sea Lion (Eumetopias jubatus)
Steller's
Sea Lions
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These are two distinct
Steller's sea lion populations. B.C.'s population of Steller's sea
lions, which breed in three rookeries in northern British Columbia,
has more than doubled since the early 1970s, to between 13,400 and
18,800 animals, including 2,300 pups (survey conducted
by the Pacific Biological Station in Nanaimo). Steller's that breed
in nearby southeast Alaska have also increased from about 11,000 to
20,000 animals over the same period. They survive mainly on herring
and other oily fish.
Steller's sea
lions in the Gulf of Alaska, west of Prince William Sound, were
declared endangered in 1997. In that part of the North Pacific,
700 kilometres northwest of B.C., a general shift in biological
makeup of the sea has reduced the amount of oily fish, and increased
the amount of pollock in their diet, which is far less nutritious
than fish like salmon or herring.
There are large
colonies of Steller's, or Northern, Sea Lions off northern Vancouver
Island, and off the southern end of Haida Gwaii, the former Queen
Charlotte Islands. The male, or bull, is a huge animal, with an average
weight of about 700 kilograms. Some may reach 1000 kilograms, with
a body length of up to three metres. The females are about a third
as large. Both are a warm brown in colour, with the bulls developing
quite thick manes around their enormous necks.
The bulls compete
with each other to maintain a harem of females, defending a territory
for up to sixty days. Gestation of the single pup is almost a year,
and pups may nurse for over a year. Females are known to live up
to thirty years.
California Sea
Lion (Zalophus californianus)
California
Sea Lion
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California Sea
Lions breed to the south of British Columbia, and after the breeding
season, the bulls disperse. Many move as far north as British Columbia,
and Alaska, and this is the most abundant sea lion in our waters through
most of the year. These bulls can be distinguished from the Steller's
by their darker pelage (which looks black when wet) and by the prominently
ridged forehead. Bulls may weigh up to 350 kilograms, and the cows
(which are not seen in B.C.) are much smaller.
This is a playful
species, which is well known as the trained "seal" in
many circuses. The population is increasing, following decades of
harvesting for meat and oil, and as threats to the commercial fishery.
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