The Gray Whale (Eschrichtius
robustus) is a whale which travels between feeding and breeding
grounds yearly. It reaches a length of about 15 meters, a weight
of 36 tons and an age of 50-60 years. Gray Whales were once called
devil fish because of their fighting behavior when hunted. The
Gray Whale is the sole species in the genus Eschrichtius, which
in turn is the sole genus in the family Eschrichtiidae.Population,
distribution and migration Two Pacific Ocean populations of Gray
Whales exist: one small population travelling between the Sea
of Okhotsk and southern Korea, and a larger one travelling between
the waters off Alaska and the Baja California. A third, North
Atlantic, population was hunted to extinction 300 years ago.
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In the fall,
the California Gray Whale starts a 2-3 month, 8 000 – 11
000 km trip south along the west coast of the United States and
Mexico. The animals travel in small groups. The destinations of
the whales are the coastal waters of Baja California and the southern
Sea of Cortez, where they breed and the young are born. The breeding
behavior is complex and often involves three or more animals.
The gestation period is about one year, and females have calves
every other year. The calf is born head-first and measures about
4 metres in length at birth. It is believed that the shallow waters
in the lagoons there protect the newborn from sharks. After several
weeks, the return trip starts. This roundtrip of 16,000 - 22,000km,
at an average speed of 10km/h is believed to be the longest yearly
migration of any mammal. A whale watching industry has sprung
up along the coast.
The whale feeds mainly on benthic crustaceans which it eats sideways
from the sea floor. It is classified as a baleen whale and has
a baleen, or whalebone, which acts like a sieve to capture amphipods
taken in along with sand, water and other material.
Above Images Are From NOAA
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