Marine Fish Part 2
Anadromous vs. Catadromus
Fishes
Anadromous Fishes
Fish that live predominantly in the
ocean but that spawn in freshwater (In
the next slide only the salmon are
anadromous)
Migration Routes of Salmon and
Tuna
The Bears (and Salmon) of Pack
Creek
An Aerial View Of A Few Islands
Landing And Wet Feet – Tide Is Going Out!
This Grizzly Just Walked Away From a HalfEaten Meal
Bonaparte’s Gulls Waiting For the Remains
Huntin Fer Food!
Drat! That Salmon Cut Right and I Went
Left!
I Finally Caught One!
Ah - A Glass of White Zinfandel Would Go
Great With This !
Spawning Salmon – Pink and Chum in July
– August period
Gulls Will “bob” For Salmon Below The
Surface
Bald Eagle – Checking Things Out Above
Pack Creek
Five species of salmon live in Alaska and
migrate at different times of the summer into
streams to spawn.
A food chain composed of many marine
organisms that culminates in salmon now is
extended to land via grizzlies, bald eagles
and an assortment of gulls ….
It is all part of the circle of life
A Small Part Of The Food Chain
Bald
Eagles
Grizzlies
Gulls
Scav.
Pred.
Adult Salmon
Roe
Catadromous Fishes
Fish that live predominantly in freshwater
but return to the ocean to spawn
Two Species Of Freshwater Eels
American Eel
European Eel
(blue)
(red)
Spawning
• Some species migrate to spawn
• Some species of fish are “broadcast
spawners”
• Others have extensive courtship displays
as in the cod and its close relative, the
haddock
• Fertilization may be internal (sharks and a
few bony fish) or external
• Number of eggs produced in a spawn is
directly correlated to extent of parental
care
Mating Behavior in the Atlantic Cod
Cod and haddock are closely related fish!