Re: [Phys-l] Doing good does bad (an example),

[Bernard Cleyet <bernardcleyet@redshift.com>]

I received a request for the original article -- my search found one  
four years ago in "Nature".

And this one:   one consequence of a fishing ban is the increase in  
necessary rescues of boats fishing further than they were intended, and:
-----------
However, a study released in May 2004 suggests that years of  
overfishing have changed the breeding tactics of cod. Cod in the  
mid-1980s began reproducing by age six, but a decade later, the  
researchers said, they began a full year earlier. What's more, the  
scientists found that the change was genetic, nor simply behavioural.  
Overfishing led to rapid evolution among the codfish, the researchers  
said.

Jack Rice, co-ordinator of the stock assessment unit at the federal  
Department of Fisheries and Oceans, told the National Post in  
September, "At some point it becomes a social choice – what does  
society want? From what you know of the politics of Atlantic  
fisheries, how likely is it that a cod stock could approach the level  
seen in the '50s and '60s?"

Answering his own question, Rice said that by the time the cod stock  
approached levels half of those in the 1950s and 1960s, a decision  
would be made to allow cod-fishing again.

"They would rather have people fishing… than continue to withhold  
catch to allow the stock to rebuild," Rice said. "We can put  
simulations on the table till hell freezes over to show if you stay  
closed another five years then your catch will be double what it is  
now and still be sustainable. [But] people want to fish now."
---------------
much more:

http://www.cbc.ca/news/background/fishing/cod.html

bc  thinks messing w/ Gaia is fraught ...

On 2009, Mar 06, , at 08:07, bernardcleyet@redshift.com wrote:

> or for what one selects, one gets.  [The first law of biology  
> according to
> G. Hardin]
>
>
>
>
> Portland Press Herald, ME - Commercial fishing might be causing
> genetic changes in fish that swim in the ocean, making them smaller  
> and
> less fertile. . . However, the study also found that fish can grow  
> larger
> again if the big ones are allowed to get away. . . Efforts to bring  
> back
> the fish still include rules - such as minimum sizes and large-mesh  
> nets
> - that encourage fishermen to catch and kill the largest fish and  
> spare
> the smaller ones. That is sending the wrong message to the fish,
> genetically speaking. . . Shrinking fish sizes also mean a population
> reproduces at a slower rate, something that makes it more  
> vulnerable to
> natural pressures such as predation and less able to recover from
> overfishing. . . Larger fish are generally much more fertile than  
> smaller
> ones.
>
> bc thanks Sam Smith (UnderNews)
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