<< I'll leave it at saying brown trout would not have to reduce any
population
to "concern" levels to have a negative impact; I refer to changing local
abundance of usually obscure animals such as aquatic insect forms, which can
have indirect effects on other species down to the phytoplankton level. Some
research has been done on these types of effects. One EPA group studied the
presence/absence of various minnow species in northern New England lakes, in
which some of these lakes have had bass introduced, some have had pike
introduced, some have had both introduced and some were spared such
introductions. The lakes without such introductions had more minnow species.
That's not brown trout in Michigan, but I'd bet half a peach that you could
find similar effects with aquatic arthropods. Not a glamorous group to most
people, but... >>
Well we would be talking very obscure changes that would occur with any
organism in any ecosystem anywhere. Slightly changes in arthropodan
populations are natural in many systems naturally, and things have a way of
balancing out. Thats the way a natural system works, and I still beleive
brown trout are not a problem in any way, shape, or form. Don't get me wrong
on one thing, though. Other introduced (or exotic) fish that are more
predacious, environmentally tolerant, ect do pose a threat. Brown trout, in
their nature, cannot pose such a threat. Long live browns...
___Dan McConnell Marshall, MI
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