Watching some Coho smolts this AM I got to wondering about their chances
of making it over the winter,there's not a Helluva lot of nutrient in
the stream they're in.
Then it came to me that they too must be feeding on whatever Roe drifts
off the Redds.
Makes sense and of course also explains the proclivity of returning fish
to be suckers for a 'gob 'o guts' when it drifts by them.
Any comment?
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Coho smolts utilize a lot of the time, the warmer ground water tributatries
(although not all the time). In the winter they will probably utilize
the small amounts of Stonefly nymphs which are available almost year round.
I personally have tryed to form hypothesis as to why salmon will bite roe,
but everytime I do, I find a reason to shoot it down. I think the reason
salmon bite roe is because of their natural curiousity. I think that is
the main reason behind it.
Scott
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Coho and steelhead smolts generally overwinter by burying into the stream
bed substrate. They generally don't feed but quasi hibernate. Once on
the Little Q I turned over a large cobble to see if there were any nymphs
- instead there was a 4 inch coho parr - complete with orange fins and tail.
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I had no idea juvies buried themselves, but that makes a lot of sense. When
ever I go exploring small streams in the winter, I rarely see juvie salmon
or steelhead. I've always wondered where they go. But at that age, they
are supposed to be gorgeing themselve on food. So how do they survive while
they are buried?? Which species do this??
I know pinks and chum migrate to the ocean soon after hatching in spring.
So they wouldn't be around for next winter to do this.
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Robert,
Coho have to over winter. They don't usually go to the ocean until they
smolt, which is a noteable size and you would probably see them.
The key thing to remember about coho populations is that they will utilize
the smallest of creeks
to rear in. Their parents spawn in these creeks for a reason! So their young
go in them right away. That is probably why you do not see coho fry/parr
on the mainstems of rivers in a lot of cases.
Scott
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"Their parents spawn in these creeks for a reason!
So their young go in them right away.
That is probably why you do not see coho fry/parr on the mainstems of rivers
in a lot of cases.
Scott"
What in the name of all that's Holy does that mean?
Gibberish is what it is,you have to start turning on the fan at work Scott
all those fumes are getting to you.
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It means that the salmon spawn in the smaller tributaries of the big rivers.
More protected, slower current. So if exploring main rivers, they wont be
there. Hard to undedrstand sometimes but I get it.
-chris
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Mickey, Chris and Ralph are right, coho do tend to spawn in the smaller
creeks. Large rivers are generally only the highway they take to get home.
However, you will find juvenile coho salmon both in small streams and in
large rivers.
Think about it. A single female lays 4000 eggs. If they all hatch, they
need to spread out in search of food and rearing habitat. The small streams
can't always support them all, so they will move out into the larger
systems. Also, some stocks spawn many, many miles away from the ocean and
the juvenile coho eventually have to get to sea. So they will migrate out
of their small natal streams and slowly migrate toward the ocean over time.
You generally don't see these fish in small streams or larger rivers
because they are hiding. Under logs, in cavities along rip-rap banks, under
undercut banks, behind boulders, in log jams, in deep pools, in off channel
habitat (side channels, wetlands, beaver ponds, etc...). They are
very wary and hide at the slightest detection of movement. You may not see
them, BUT, they are there. Try sitting very quietly on the bank away from
other people for about a half hour. You'll see them then. They will
come out of hiding if you don't move.
In winter, coho, chinook and steelhead all basically enter a state of torper.
Their metabolism slows down to next to nothing. They do not move around
a lot, they rarely feed and growth slows down considerably. This causes
the narrow growth ring on a fish scale that is used to age a fish (same
thing happens with trees). Again they will hide and they will seek out
areas where the current is very, very slow like deep pools (less energy
expended to maintain station). This includes the spaces between the
gravels and boulders on the substrate. When electroshocking a stream in
winter, the gravel is often "kicked" to dislodge any fish that may
otherwise not rise after shocking.
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I slashed a Hydro line a few years ago on the Birkenhead River N. of Pemberton
and the manmade ponds under the lines were stuffed with young coho hiding
in the cut brush dumped in these ponds.The creek connecting these ponds
was only about an inch and a half deep.Ran into a local C.O. while we were
working and wondered whether there was much of a return from such artificial
habitat.He assured me that returns from these small square ponds connected
by tiny little streams had to be seen to be believed when the adults were
spawning and that percentages were better than hatchery numbers.I think
the depth of pond (8-10ft) and log jam of cut brush must have been
an anti-predation factor here.I believe it was a BC HYDRO environmental
impact project.
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