From Deseret News archives:
Limiting catch to large fish may tilt evolution
That, at least, is the concern of researchers who studied test populations in two artificial lakes and report their findings in this week's edition of Proceedings of the National Academy of Sciences.
Peter A. Biro of the department of environmental science at the University of Technology in Sydney, Australia, explained that it's the fast-growing more aggressive fish that tend to get caught, removing them from the breeding pool.
That leaves reproduction up to slower-growing fish who are more timid, he explained in an interview via e-mail.
"This will cause evolution to slower growth rates and slow the rate of recovery for fished populations, and could explain why fisheries tend not to rebound in the manner we expect after we reduce harvest or close a fishery," he said.
"What surprised me was how fast it occurred," Biro said. He said the largest catch occurred on the first day of fishing.
They set gillnets in the ponds over five days, moving them each day, and caught 50 percent of the stocked fast-growing fish but just 30 percent of the more cautious ones.
"Fish that are highly active and bold tend to bump into these nets more often and are less likely to avoid them," he explained. And increased activity is necessary to get enough food for rapid growth.
John Waldman, an aquatic biologist at Queens College in New York, called the report important.
"Harvest of fishes is probably the most profound impact mankind is having on the sea, yet we rarely succeed in even the basics of achieving long-term sustainability of important commercial species," said Waldman, who was not part of the research team.
The report shows that "differences in 'boldness,' which are positively correlated with grow rate, render bold individuals more vulnerable to harvest, thereby adding an important and, till now, unconsidered direct effect to the known indirect effect" of fishing, Waldman said.
"The implication for managers is that the continued reproduction of a meaningful portion of fast growing individuals is likely even more important than previously recognized," he said.
The research was supported by the University of Technology Sydney and the National Science and Engineering Research Council of Canada.
On the Net:
PNAS: www.pnas.org
Comments
- Coaches decline to call BYU-Utah 8:37 p.m.
- Holiday could bring more H1N1 8:36 p.m.
- Man stabbed in road-rage incident 8:34 p.m.
- Utah firm offers writable disc 8:29 p.m.
- Family fun center is completed 8:26 p.m.
- Chambers make wager on Y.-U. game 8:25 p.m.
- Saab brand may go extinct 8:24 p.m.
- Facebook creates stock structure 8:24 p.m.
- Turkey-tip talkers set for onslaught 8:23 p.m.
- 3 airlines fined for roles in incident 8:23 p.m.
- Utah, BYU are top choices for bowls
- BYU would like friendlier rivalry
- Protests against Phoenix LDS temple
- Best prep football games of 2009
- KSL: Prostitution in Utah County
- Man trapped in own body for 23 yrs
- Kirilenko climbing blocks list
- Woman describes stabbing, killing
- Boys basketball rankings
- 'Dancing' will fill out finale
- BYU would like friendlier rivalry
227 - Glenn Beck to enter politics?
223 - RSL wins MLS Cup on penalty kicks
202 - Protests against Phoenix LDS temple
181 - Palin plans tour stop in Utah
179 - Bronco, Kyle rubber match
137 - Palin's book shows she's unqualified
136 - BYU records with win
133 - Letters: Rushing to judge Palin
117 - Officer cleared in Cardall Taser case
104
I am so sorry to hear of Mark's death. I also knew him personally during my...
@Nate: Take me up on my challenge about the war. Is he trying to fix...
Oh goodie! The globe warms and we can't do anything about it. Guess it's...
Anything that is not part of fundemental christian churches will sound odd.If...
Growing up, we had seats in the South End Zone behind the band & students....
On the chance that actual facts about traffic might be of interest, I went...
re: Gary | 2:16 p.m. Nov. 24, 2009 I'm w/ you. I'm a Utah native & U grad...
I think V is great. The finale was a real cliffhanger. I am holding out hope....
In soccer 3pts/win system there is a simple measure over the regular season....
To: Hammy Sammy [We can see in the last ten months, how Obama runs...



You can be the first to comment on this story.