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Old 03-01-2013, 03:43 PM
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The article was remiss in failing to point out that the current 4 year old trout that seem to be in short supply in the eastern LA fisheries were juveniles in 2010 when the Deepwater Horizon oil spill occurred. Current 3 year old trout were in the 2010 birth class. The impact of the oil spill on spotted seatrout has been studied in detail, but the final results have not yet been released. See:

http://www.northerngulfinstitute.org...ct.php?pid=150

It would be a shame to put the blame on overfishing for reduced stocks and reproductive potential if the oil spill was really a dominant factor in the current dip.

It would also be an error to reduce limits on spotted seatrout before it is better established that the number of adults rather than habitat or some other life history issue is the biggest bottleneck regarding recruitment of new seatrout into the fishery.

The Draconian limits on red snapper assume that the biomass of breeding adults dominates the number of age zero and age 1 fish entering the fishery, but after many years of study it finally seems clear that other life history details dominate the number of age 0 and age 1 fish and the number of recruits entering the fishery is not strongly correlated with the biomass of breeding fish.

It is well known that if there are fewer breeding adults, they eat a lot better because there is less competition for available food. Better body condition from available forage can lead to much higher fecundity rates. Half the number of plumper breeding fish can produce more eggs than twice the number of poorly fed fish. Fecundity rates depend strongly on body condition.

The article also missed the possibility that reduced numbers of large fish may be due to slower growth rates caused by greater competition for food due to underharvesting of smaller fish or some other factor having a significant negative impact on the food supply. This can be studied either with a growth rate study or with a relative condition factor study. If the fish are overharvested, then the remaining fish will be plumper for their length because they are well fed. If the fish are underharvested, they will be thin.
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