--Bruce Stallsmith
Huntsville, AL
>But the geniuses behind the project obviously didn't study up on minnow
>biology,
>for it's a well-known fact that minnows release a fear scent (called
>Shreckstoff) whenever they're bitten by a predator. This sends a message to
>their schoolmates which says, basically, "Let's get the hell outta here!"
>
>The electrocution device worked for a while, but then the pikeminnow
>abruptly
>stopped entering the ladder. Apparently, the shocked pikeminnow were
>releasing
>their Shreckstoff, which alerted the pikeminnow below the dam that danger
>lurked
>ahead and to stay where they were.
>
>This only served to compound whatever predation problem may have existed,
>because a huge mass of adult (and therefore large--we're talking 3-4 ft)
>pikeminnow congregated below the dam, feasting on whatever salmon
>congregated
>there as well!
>
>The "problem" more or less took care of itself when the dam managers merely
>left
>the gates of the dam open, allowing the passage of migrating salmon
>through the dam. Which, not coincidentally, allowed pikeminnows to complete
>their spawning migration as well.
>
>Suffice it to say, the electrocution device was subsequently removed.
>
>
>
>Christopher Scharpf
>Baltimore
________________________________________________________________________
Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com
/-----------------------------------------------------------------------------
/"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