of Japanese Coastal Orcas
of Japanese coastal orcas, including pod sizes, major travel pattern
and routes has not been clearly understood, and it is apparent
from the ﾒNatural Resources Evaluation Reportﾓ published by the
Fisheries Agency. The population estimate is made from an analogical
estimate using similar species whichﾕs population is under research
by employing sight survey. It is said that there are 1,600 orcas
in the Pacific Ocean side (from Bousou to Hokkaido approx.900),
and 721 orcas in Okhotsk Sea.
There are a few different types of
orcas according to their behavior. The major types divide into
two: the Resident (stay closer to the shore, eat fish) and the
Transient (travel more eat mammals). Which type the Japanese coastal
orcas fall into is not yet understood.
On the other side of the
Pacific Ocean along the west coast of North America, studies on
orca societal structure and behavior have been showing great progress,
using individual identification. Researchers concerned about the
population decline due to heavy capture for aquarium displays during
the 1970s carried out a studies and showed that there were only
one thousand a little more for both residents and transients combined.
Before the result came out it was believed that there were several
thousand animals each. Considering this and the fact that there
had been orca hunts along the coast of Japan in the past, it seems
more logical to assume that there are fewer orcas than what is
currently estimated. There is small private research stations set
up in Japan working on small projects, but the government tends
to shy away from doing research from animals with no merit in terms
of natural resources.