JAPANESE SEA LION
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Japanese Sea lion at Liancourt rocks in 1934 |
Distinctive characteristics
Japanese Sea
Lion was considered to be a subspecies of Californian Sea lion but in 2003 it
was proven that this aquatic mammal was a unique species of sea lion. It is
also known as a Black Sea Lion. It was the member of eared seal family together
with fur seals and other sea Lions which is different than true seals as they
have the small eternal earflaps and hind flippers that can be turned to face
forwards. This gives a great sense of mobility to eared seal the same feature
that the Japanese Sea Lion possessed. Not much is known about the appearance of
sea lions but its other name the Black sea lion shows us that adult males had a
darker color while females had lighter color similar to brown. We know this
as the development of photography helped us to see these magnificent sea
creatures at least in pictures. The adult males were at average 2.5 meters in
length and weighed from 450 to 560kg, adult females were around 1.4 meters so
they were a lot smaller than the male specimen in length while a four month old
pup was 65 cm long and 9kg in weight. Japanese Sea Lion’s diet was consisted of
fish that it could find around its habitat.
Dental Formula Not known
Size
Male Japanese sea lions were dark grey, reaching
lengths of 2.3 to 2.5 metres (7.5 to 8.2 ft.) and weighed about 450 to 560
kilograms (990 to 1,230 lb.). Females were significantly smaller at 1.64
to 1.8 metres (5.4 to 5.9 ft.) long and weighed about 120 kilograms
(260 lb.) with a lighter grey colour than the males. A four month old pup was 65 cm long and 9kg in weight.
Use and Trade
Japanese Sea Lions were
harvested for their skins, whiskers, internal organs, and oil, and were also
captured for the circus trade. The species is now Extinct.
Habitat
Even
though the animal is called Japanese Sea Lion it extended further from the
maritime area of Japan. The range of this specimen was Northwest Pacific mostly
Japan, Korea and Russian Kamchatka island. Unlike other sea lions Japanese sea
lion liked to be more in the caves a fact that cannot be explained rationally.
They had only went to the beach during the mating period and sometimes the
mating period took place at the stony beach.
Diet /feeding
The diet for this species of Sea Lions
consisted of various fish found in the waters in their habitat.
Breeding
Reproduction for the Japanese Sea Lions took place
both on sandy beaches and sometimes in rocky areas.
Threats
Japanese Sea
Lions were harvested for their skins, whiskers, internal organs, and oil, and
were also captured for the circus trade. Those takes, in combination with
persecution by fishermen and perhaps shooting by soldiers, likely caused their
extinction.
Geographic Range
According to Rice
(1998) Japanese Sea Lions formerly were known from the northwest Pacific where
they occurred along the coasts of Japan, the Democratic People’s Republic of
Korea, the Republic of Korea, and Russia at Sakhalin Island and southern
Kamchatka. Burkanov (pers. comm.) says that the only reliable report of
Japanese Sea Lions was of an animal shot in 1949 at Moneron Island in the Sea
of Japan at the southwest corner of Sakhalin Island. He concludes that they
occasionally occurred in the southern Kuril Islands but not at Kamchatka as
Rice (1998) had stated.
Extinction
This
animal did not have any natural enemies except humans who used its meat for
food and also its skin and oil. The oil was used to make old lamps, the skin
was used to make clothing like shoes and even blankets. The internal organs
were used to make various remedies. The whiskers were used to make pipe
cleaners. The fishermen had also hunted the Japanese sea lion so they can have
more access to fresh water and that they can catch more fish. Another thing
that contributed to their extinction is a submarine warfare during the WW2 as
it had destroyed their natural habitat.
It
is estimated that 30,000 to 50,000 Japanese sea lions existed in the nineteenth
century. Japanese fishermen reported that they harvested 3,200 sea lions in the
beginning of the 20th century. The population fell to 300 in 1915 while in
thirties the number was not even close to fifty. The commercial harvest stopped
in 1940s as Japanese sea Lions were at the brink of extinction.
The
last known observation of Japanese Sea lion happened in 1951 and it was of
fifty to sixty seals which had been seen on the Liancort Rocks
(Japanese-Takeshima; Korean –Dokto or Tokdo). Sightings have been reported in
1970s, though none were confirmed and it was declared extinct. The scientific
community was glad when they heard that there were sightings of Japanese sea
lion in 2003 but in the end those were confirmed to be Californian sea lions.
South Korea, Russia and China decided to try to recreate the Japanese Sea lion
if that is not possible they planned relocate the Californian Sea Lion to the
previous habitat of the Japanese sea lion.
Justification
The species
is listed Extinct because there have been no documented reports of Z. japonicus
since the late 1950s, despite extensive marine mammal research effort taking
place within its former range. The last credible report was 50 to 60 individuals
on Takeshima (Dokdo) (in 1951 (Rice 1998). Individual sightings reported as
recently as 1974 and 1975, cannot be confirmed; confusion with escaped Z.
californianus cannot be ruled out.
Red List Assessments
2015 – Extinct (EX)
2008 – Extinct (EX) 1996 – Extinct (EX) 1996 – Extinct (EX) 1994 – Extinct (Ex)
1990 – Extinct? (Ex?) 1988 – Endangered (E).
IUCN status probably extinct
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