There are more than 15 kinds of fishery that are found in lake Toya.
One of them, Cherry salmon is now coming back into those streams to lay their eggs.

They are better known as "Yamame" when they live in streams.
However, some of them go downstream until they meet ocean,
they grow in salt water for a couple of years and come back.
It sounds like "the" salmon, but species are different.

But, hey!!
"lake Toya is NOT connected to ocean!!"
"nope"
"this is one of the rare example that this Cherry salmon growing in fresh-water"

They use all thier strength to come back stream, they hardly eat once they are back.
All they want is to lay their eggs, leave their next generation.
All of them die after this "peak of life" event.

Their dead bodies, again come down stream and some reach lake Toya,
are very rich in nutrition for sea-gulls, fox, racoon, and other fish that live near-by.

This real thing is going on @ lake Toya, maybe, until the end of this month.
Then those salmon starts coming back from Pacific ocean.
(yuji)