"rw" wrote in message
ink.net...
Wolfgang wrote:

"rw" wrote in message
nk.net...


Producing hatchery fish -- even ones bred from wild stock -- doesn't
change the genes...


Yes, it does. Every environment has its mutagens. No two are the same.

That's true, I suppose, but it's a very small effect over just one
generation,

How many hatcheries that you know of operate for just one generation?

and probably not even measurable because sustainable mutation rates are
low.

Certainly not measurable, but not for the reason you state. Mutation rates
are not only highly variable from one species to another, but can also be so
within a single species for a number of reasons, not the least of which is
the presence, character, and relative abundance of mutagens. Before one can
say anything meaningful about mutation rates in a given species, one has to
know a lot more about its genetics than we currently do about any of the
salmonids.

Most short term variation in genetics (by far) comes from sexual
reproduction and the resulting combination of alleles, and not from
mutation. That's Biology 101.

Actually, that information is readily available in high school biology
texts, any decent encyclopedia, back issues of "Scientific American" and
quite possibly even on the internet (check with Google); one hardly needs to
wait for college.

The point I was making,

Poorly......but, go on.

if you can just stop wanking for a moment,

Just CAN'T get that image out of your brain, huh? I wonder......do you
fantasize in great detail.....or is it just fuzzy images?

is that hatchery production affects the genetics of populations,

Not as startling as the revelation that sunglasses aren't primary source of
light on Earth, but interesting nevertheless. You might want to approach
some institution of higher learning with that thought and see if they can
run with it.

if not (very much) the actual genes themselves.

Again, that remains to be seen.

I'm not as alarmed about hatchery production of steelhead and salmon as
some people are.

Evidently.

I don't doubt that hatchery production adversely affects the gene pool
(from our point of view as fishermen), but the real problem is habitat
loss and degradation. Hatcheries should be seen as temporary, stop-gap
measures. If the habitat were somehow magically restored to its pristine
condition (not likely) and hatchery production were stopped, the
population genetics of fish would return to a "normal" wild state in a few
generations, under normal wild selection pressures, as long as the
underlying genetic diversity hadn't been lost.

Restoring habitat to a "pristine" condition would indeed require magic.
There are two approaches to the problem, I think. One; we could simply
leave a particular habitat alone......no contact with humans and no
influence from any human activity (or what does "pristine" mean?). This is
the passive approach......and it simply isn't going to happen. Two; active
restoration requires deliberate and intensive human intervention......which
is sort of the antithesis of what a pristine environment requires, ainna?

Good luck.

Wolfgang