New method of counting fish unveiled
by Kirk Moore, CentralJersey.com (excerpts)
After years of complaints from recreational fishermen that government catch data didn’t correspond with what was actually happening on the water, The National Oceanic and Atmospheric Administration announced (NOAA) on Wednesday it has begun to use an improved method to estimate the amount of fish caught by saltwater anglers.
The new method, the Marine Recreational Information Program (MRIP), is intended to take the place of the Marine Recreational Fishing Statistical Survey (MRFSS), a data collection program whose accuracy has long been called into question. MRFSS information has been the basis for the regulations that govern recreational catch limits, sizes and seasons.
Along with its announcement of the new method, NOAA also released recalculated estimates going back to 2004. In its release, the agency reported here were no overall trends in terms of size or direction of the new estimates — catch estimates for some species went up, some went down and others remained about the same.
One of the biggest confounding factors in the old MRFSS system was a bias from using mostly interviews from “high activity sites” – busy docks and fishing spots where MRFSS surveyors could most efficiently interview fishermen.
“High activity sites weighted heavily” in the calculations that went into the MRFSS estimates, said Eric Schwaab, the acting assistant secretary of commerce for conservation and management. “The scientists and the statisticians have gone back and rooted out a lot of that old bias.”
Relying on high activity sites for interviews appears to have been the biggest source of bias in the surveys, said Gordon Colvin, the MRIP manager, and a fisheries biologist who used to head New York State’s marine fisheries program.
According to NOAA fact sheets and revised data, it looks like using more interviews from the busiest locations had implications for skewing estimates on summer flounder, cod in the Gulf of Maine and striped bass on Long Island. Along with statistical compensations for that past bias, Colvin said the new MRIP methodology will look to use more information gathered at low-activity areas like surfcasting beaches….
In 2005-2006 the National Research Council examined the MRFSS methodology and found it wanting. Congress followed up by directing NOAA to overhaul the system.
It’s taken a long time to do the research, design a new system and submit it to peer review by independent scientists, Colvin said. Then the methodology had to be brought to bear for recalculating estimates for some 500 regional fish stocks, he said.
“In some cases these data will be significant enough to change a stock assessment,” Schwaab said. For most species the estimates will serve to guide management actions, he said….
To view comparisons of recreational catch estimates using the previous method and the revised method, go to: http://www.CountMyFish.noaa.gov.
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