Also, esocids don't show parental care like centrarchids and
ictalurids. I've been thinking about fish-eating fish and why there aren't
many in western US and Canadian freshwater habitats. We have lots and lots
of birds here that eat fish-- herons, cormorants, mergansers, terns,
several species of kingfisher, eagles, and more-- but few fish that eat
fish. I wonder that this isn't partially because so much of the biomass in
streams is of anadromous fishes and their fry-- salmonids, osmerids,
clupeids mostly. So a fish-eating fish would have slim pickings during
portions of the year, and they'd have to chow on minnows and suckers and
sculpins and such. That's likely a limiting factor on the numbers of these
fish, which would be restricted to the immediate area, moreso than birds,
which can fly elsewhere for food.
I'm also wondering a few things about the threat of the northern pike in
Lake Davis:
Is it really a threat to the endangered salmonids or is it a threat to
lucrative fisheries there? California has been promoting fisheries on
intentionally introduced fishes like largemouth bass and striped bass as
long as I can remember. I wish someone could shed some light on that.
-- Jay DeLong Olympia, WA /----------------------------------------------------------------------------- /"Unless stated otherwise, comments made on this list do not necessarily / reflect the beliefs or goals of the North American Native Fishes / Association" / This is the discussion list of the North American Native Fishes Association / nanfa_at_aquaria.net. To subscribe, unsubscribe, or get help, send the word / subscribe, unsubscribe, or help in the body (not subject) of an email to / nanfa-request_at_aquaria.net. For a digest version, send the command to / nanfa-digest-request_at_aquaria.net instead. / For more information about NANFA, visit our web page, http://www.nanfa.org </x-flowed>