NANFA-- brown trout (was Spawning in high water...)

Christopher Scharpf (ichthos_at_charm.net)
Mon, 28 May 2001 00:05:51 -0400

Dan wrote:

> I still beleive brown trout are not a problem in any way, shape, or form.

It's well-documented in the literature that brownies have reduced native
salmonid populations -- especially brook trout -- through displacement, food
competition, and outright predation. I direct your attention to one study in
particular: Fausch & White, 1981, Competition between brook trout and brown
trout for positions in a Michigan stream, Canadian Journal of Fisheries and
Aquatic Sciences 38: 1220-1227. This study showed that brownies pushed out
native brookies from the best habitats.

In addition, brownies have been implicated in the decline of Dolly Varden,
golden trout, and Modoc sucker in California, and the near-extinction of
Lahontan cutthroat trout in Lake Tahoe.

Comparatively speaking, brown trout are probably not as dangerous and invasive
as other exotics. In fact, they have failed to establish reproducing populations
in most areas into which they've been introduced. But to say that they are a
benign presence is a gross underestimate of their destructive record and
potential. They clearly should not be sanctified.

Chris Scharpf
Baltimore

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