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For "Overfishing is a legal term, not a scientific term, and is therefore 
not an
accurate way to evaluate the health of the scallop fishery, Dr. Kenchington
said."

1. Really, it is a problem.
2. The problem is the definition of overfishing.
3. If carrying capacity is tme-varied then net production (rate) is also 
time-varied.
4. From Schaefer model, following catch curve can be obtained. 
Yi=qKi{1+(1/r)ln(Bi,t/Bi,t+1)-Fi/r}
5. Clearly, catch is depending on carrying capacity, intrinsic growth rate, 
current biomass and fishing intensity.
6. Then, what is overfishing?  What is the healthy sotck?
7. Any regulation of fishery should be based on above four factors; F, K, r 
and B

----- Original Message ----- 
From: "Mike Flaherty" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Thursday, May 26, 2005 9:04 PM
Subject: Is overfishing a scientific or legal term?


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> An article titled, "Scallops overfished for past 2 years, official says",
> appeared on the front page of today's New Bedford Standard Times.
>
> http://www.southcoasttoday.com/daily/05-05/05-26-05/a01lo102.htm
>
> There was one excerpt in it which gave me pause...
>
> ===============================
> "Overfishing is a legal term, not a scientific term, and is therefore not 
> an
> accurate way to evaluate the health of the scallop fishery, Dr. 
> Kenchington
> said."
> ===============================
>
> As I roughly understand things, "overfishing" is defined as a point beyond
> which harvest/mortality levels exceed sustainable levels in a fishery.  It
> is further my understanding that the thresholds for sustainability are
> arrived at scientifically.  If this is true, then isn't overfishing truly 
> a
> scientific term?  More importantly, is it a reasonably accurate way to
> evaluate the health of a fishery?
>
> Thanks,
> Mike Flaherty
> Wareham, MA
>
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