An animal that is believed to be a Steller's sea lion photographed in Tokyo Bay.
Why did you come to this place?
Is it okay to stay in this place?
We asked an expert who is familiar with the ecology of Steller sea lions.
The answer was given by Dr. Yoko Goto, Senior Researcher at the Wakkanai Fisheries Experimental Station of the Hokkaido Research Organization.
Q.Is that creature photographed in Tokyo Bay a sea lion?
.
A. I saw the picture, but that is a sea lion.
According to the report, the body length is about 1.5 meters, but adult females are about 2 meters long, so if it is about 1.5 meters, I think this Steller's sea lion is a child.
Q.Why are there Steller sea lions in Tokyo Bay?
Where are you from?
A. I think they got separated from the herd and arrived.
This is a very rare case.
Steller's sea lions usually live in the sea around Sakhalin, Russia, originally in Karafuto, but around the end of October they head south in search of food, appearing off Cape Soya in Wakkanai City, Hokkaido, where more than 1,000 giant sea lions can be found. create a herd.
It is thought that the Steller's sea lion this time was in the sea north of Hokkaido, but got separated from the herd and went south and reached Tokyo Bay.
You may have come to that place thinking, "I can't go on land."
Q. Can even one Steller's sea lion return to its original place?
A.There is no herd.
I think it would be difficult for one to return to the north of Hokkaido on its own.
Q.Is Tokyo Bay a good environment for sea lions?
Can you live in that place?
A. Steller's sea lions can live for a while if they have octopus, squid, etc.
In terms of water temperature, it's winter now, so I don't think it's a problem.
However, if the Steller's sea lion is healthy, it will spend its time diving into the sea and catching fish.
Land when you are weak.
If you are on land for a long time, you may be tired.
Q. Steller's sea lions have been designated as a "near-threatened species" by the Ministry of the Environment, haven't they?
A. Yes.
exactly.
On the other hand, in Hokkaido, it is causing damage to fisheries, such as eating salmon caught in fixed nets.
Plans are also being made to manage the population numbers that come near Hokkaido.
There is only one Steller's sea lion in Tokyo Bay, so I don't think it will be affected, but I would like you to keep an eye on it.