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Wildlife
of the Pacific
Blue Whale
Balaenoptera
musculus
The blue whale is
the largest animal to have ever lived on Earth. It weighs up to
136,000 kg and is as long as 34 m. It is pale blue-gray in colour
with a tiny dorsal fin. Blue whales occur in cold and temperate
regions where the water is deep. They travel alone, as mother and
calves, and rarely as adult pairs. Only occasionally do they
gather in loose groups to feed. The blue whale is found in all the
oceans of the world. The blue whale is known to occur in the
Arctic, Atlantic, Indian, and Pacific oceans. . There are three
subspecies. B. m. intermedia occurs in Antarctic waters,
B. m. musculus is found in the northern hemisphere and
B. m. brevicauda also known as the pygmy” blue whale is found
in the southern Indian Ocean
and southwest Pacific Ocean. The number of blue whales was greatly
depleted by commercial whaling before 1964.
Blue Whale
Feeding
Behaviour
The blue whale
eats mostly on euphasiids
or ‘krill’ during the summer feeding season and lives off
stored fat for the remaining eight months of the year. Blue whales
make shallow dives that last for 10 to 20 minutes while feeding on
krill near the surface. Deep dives are preceded by headstands that
reveal wide tail flukes. Returning to the surface, the whale
exhales blows that rise about 10 meters in the air. Blue whales
eat over five tonnes of food each day during the summer feeding
season. During the other 8 months of the year, it apparently
doesn't eat anything, living off of stored fat. The blue whale
gulps in large quantities of krill and seawater and then uses it
tongue to forces the water out through the baleen plates.
Northwestern Crow
Corvus caurinus
Wily,
noisy and ubiquitous, the northwestern crow is a
seashore predator of marine
invertebrates, and birds’
eggs and chicks along the Pacific Coast from
Washington to southern Alaska. The crow is found mostly
around human habitation but it also occurs along beaches
and on
seabird islands.
The
major food items include a variety of marine and
terrestrial invertebrates. Its diet includes a beach
smorgasbord of clams, whelks, crustaceans,
sea urchins and small fish. On land it eats,
insects, eggs and nestlings of cormorants,
gulls, songbirds,
oystercatchers, auklets, and
herons, as well as fruits, and carrion. Some surplus
food is cached for later consumption.
Learn more about Northwestern Crows |
