River fishes in natural habitat in Japanese subarctic(North)

[odyssey]

Hi everyone.
I traveled to Hokkaido of the subarctic zone in the Japanese most north by a car and a ferry in the summer holidays.
I have toured through wide range by a car and a ferry.

Though intense heat day continued in Japan of this year, and the best temperature was more than 35 degrees Celsius day after day,
the water temperature of the riverhead basin of Hokkaido was 8 degrees Celsius.

Dolly varden.
Fish of the salmon family which lives in the uppermost stream area of a valley stream and the source part.
We call the fish "Osyorokoma".
The water temperature of the swamp where they live was 12 ℃ from 8 ℃.
Video clip is blow.
http://www.youtube.com/watch?v=kqvrBuwEMt0

Salvelinus malma malma (Dolly varden)




White-spotted char
They inhabit downstream than Dolly varden.
We call them "Amemasu". "Amemasu" is a meaning called "rain trout".
The greatest individual grows up to full length 70-80cm, 7kg.
Video clip is blow.
http://www.youtube.com/watch?v=YEXzTAFYvK0

Salvelinus leucomaenis leucomaenis (White-spotted char)


A video of loach will be raised to a loach forum later.

Japanese fluvial sculpin , Bullhead.
Fish eater they imitate in a stone of geobenthos.
Well, there is this fish under White-spotted char of the previous picture.
Video clip is blow
http://www.youtube.com/watch?v=juLVjYuQ5ek

Cottus nozawae (Japanese fluvial sculpin , Bullhead)



The freshwater fish which is the downstream from a mouth of a river.
It's possible to see much amphidromous migration fish there.
Video clip is blow.
http://www.youtube.com/watch?v=bQJcq-OM4SU

Rinogobius sp.




Gymnogobius opperiens

[Mad Duff]

Stunning pics and vids

[piggy4]

Awesome really interesting

[Jim Powers]

Amazing!!

[Matt]

Great, great stuff Odyssey. So this Rhinogobius sp. inhabits very cool water?

[Hokum]

Fantastic pictures. I'm still wanting to get some Rhinogobius sp for my river tank!

[odyssey]

Hi Matt.

Great, great stuff Odyssey. So this Rhinogobius sp. inhabits very cool water?

The coastal region is warmer than an inland area. But when winter comes, this coastal area is also covered up by snow.

[Hokum]

Are all Rhinogobies 100% fresh water or are some freshwater then the fry go to the sea then swim back upstream?

[odyssey]

Hi Hokum.

Are all Rhinogobies 100% fresh water or are some freshwater then the fry go to the sea then swim back upstream?

There are a lot of fish species of the amphidromous migration which goes back and forth between a sea and a river in freshwater fish of a goby family.

Rinogobius is also almost amphidromous migration.
There are few fish species propagated only at a river.
It seems necessary to lay big egg to propagate by pure fresh water.