E-M:/ Perch decline

[Sue Doersch <doersch@win.bright.net>]

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Enviro-Mich message from Sue Doersch <doersch@win.bright.net>
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Marquette's Channel 6 news' web site reports today that researchers 
looking into the decline of Lake Michigan's perch population found very 
few females when they netted last week.  First try, 5300 fish, 3 of them 
female; second try 885 fish, 1 female; third try 800 fish, no females.  

http://www.msnbc.com/local/WLUC/3.HTM

Says they were university researchers, doesn't say which university.  
Doesn't say where in Lake Michigan.

Does anyone know more?  

Could the nets have missed the females somehow?

I recall reading that netting in the last several years has turned up 
disappointing numbers of young, but I don't remember anything about too 
few females.  Is this the first time?  I've seen speculation that the 
young aren't surviving because alewives eat them, spiny water fleas 
outcompete them for food, and zebra mussels clear the water of nutrients 
needed by the creatures young perch eat.  But is it known that the perch 
have been reproducing?  

How are perch doing at inland lakes?

Sue Doersch


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