Forgotten Treasures #20: THE STORY OF A SALMON

"Cyli" wrote in message
...
On Tue, 3 Jul 2007 23:15:52 -0600, "Wolfgang"
wrote:


I suspect that, whatever was known scientifically, the common meme was
that fish returned to their birthplace.

Where stream dwelling fish are concerned, this would undoubtedly have been
common knowledge in prehistoric times. Aside from direct observation of
fish moving upstream to spawn in the same areas in which they were hatched
themselves, it would have been self-evident that those who failed to do so
would quickly breed themselves out of their native ecosystems.....as is, of
course, also true of the bugs and other critters they feed upon (thus
raising the question of how aquatic plants manage to maintain a foothold).

Assuming that this common knowledge also applied to lake and ocean dwelling
fish, support for it would probably not have been as easy to observe
directly, especially where the latter are concerned, but still easy enough
in many instances to support a generalization, I suppose.

I learned it in the 1940s
from my father, who must have learned it prior to 1920, as that's
where most of his memes came from (as well as most of what real
knowledge he had). This was told to me as being true of all fish, not
just migratory ones.

The beauty of searchable digital text......

I didn't recall that Jordan had anything to say about the issue of salmon
returning to their natal streams to spawn in "Science Sketches," but I just
did a search on the term "spawn" and found this:

"It is the prevailing impression that the salmon have some special insticnt
which leads them to return to spawn in the same spawning grounds where they
were originally hatched. We fail to find any evidence of this in the case
of Pacific coast salmon, and we do not believe it to be true. It seems more
probable that the young salmon hatched in any river mostly remain in the
ocean within a radius of twenty, thirty, or forty miles of its mouth.
These, in their movements about in the ocean, may come into contact with the
cold waters of their parent rivers, or perhaps of any other river, at a
considerable distance from the shore. In the case of the quinnat [king
salmon. ws] and the blue-back [sockeye salmon. ws], their 'instinct' seems
to lead them to ascend these fresh waters, and in a majority of cases these
waters will be those in which the fishes in question were originally
spawned. Later in the season the growth of the reproductive organs leads
them to approach the shore and search for fresh water, and still the chances
are that they may find the original stream. But undoubtedly many fall
salmon ascend, or try to ascend, streams in which no salmon was ever
hatched. In little brooks about Puget Sound, where the water is not three
inches deep, are often found dead or dying salmon, which have entered them
for the purpose of spawning. It is said of the Russian River and other
California rivers, that their mouths, in the time of low water in summer,
generally become entirely closed by sand-bars, and that the salmon, in their
eagerness to ascend them, frequently fling themselves entirely out of water
on the beach. But this does not prove that the salmon are guided by a
marvelous geographical instinct which leads them to their parent river in
spite of the fact that the river cannot be found. The waters of Russian
River soak through these sand-bars, and the salmon instinct, we think, leads
them merely to search for fresh waters. This matter is much in need of
further investigation, at present, however, we find no reason to believe
that the salmon enter the Rogue River simply because they were spawned
there, or that a salmon hatched in the Clackamas River is more likely, on
that account, to return to the Clackamas than to go up the Cowlitz or the
Des Chûtes. 'At the hatchery on Rogue River, the fish are stripped, marked,
and set free, and every year since the hatchery has been in operation some
of the marked fish have been re-caught. The young fry are also marked, but
none of them have been re-caught.' The shad is another species of fish
supposed to possess this remarkable homing instinct. Shad have been planted
in the Sacramento River, and considerable numbers descended from the plant
have been already taken in the Columbia River and in Monterey Bay, but not a
single one, so far as is known to me, in the original stream, the
Sacramento."*

I think the meme got simplified somewhere along
the way from reality to my ear. Many of the things I was taught by my
father had that problem.

Many of the things learned by most people from most sources suffer from that
problem.

BTW, the mated for life thing with birds does pretty well prove true.
In cases where one of the partners indulges in a spot or even a whole
season, of infidelity, they return to one another for the rest of life
in all the cases I've heard of. Mated for life doesn't seem to a bird
to mean anything like a law of sexual fidelity, though they often act
as if it does. More like a general rule. It's also been noted that
if one partner dies, the remaining one does not don mourning and waste
away. They find someone else, if possible.

Thus demonstrating that "mated for life" is not quite the same thing as
"lifelong monogamy.

Wolfgang
*from "The Salmon Family" in "Science Sketches" pp. 58-60.