Pages

Monday, March 26, 2012

Estimating Recreational Catch: The New Marine Recreational Information Program (MRIP)

For many of us, our jobs directly or indirectly have to do with estimating fish populations.  We may be part of a project that samples specifically to estimate abundance or productivity, or we may be working on a specific biological question that has demographic implications.  For all stock assessments, harvest (catch or removal) is a critical part of the estimate and combined wit
h natural mortality is the entire loss term for a population. Estimating commercial harvest has its difficulties (for example, bycatch and discard), but natural bottlenecks such as fish houses and trip tickets help prevent information from being lost.  Estimating recreational catches, on the other hand, can be very difficult as the number of licensed fishers doesn't always correlate well to effort and there is generally no way to report landings.  However, recreational catches can still be a significant portion or majority of landings for a species, so getting this information correct is essential for successful management.

Recreational pier fishing. (Photo: John Sullivan)
Since the late 1970s, the National Oceanic and Atmospheric Administration (NOAA) has relied on MRFSS, the Marine Recreational Fisheries Statistics Program, to estimate the impact that recreational fishing has on fish stocks as well as to develop estimates of harvest limits, enacted through creel and size restrictions.  In a nutshell, MRFSS estimates effort (trips) through telephone surveys and catch (fish) through dockside sampling.  Effort and catch are then used to arrive at an estimate of the harvest.  Measures to improve both effort and catch are continually being assessed and improved, so that the final estimates are a more accurate description of the current fishery.

Recreational Fishing Data Collection (Photo: Nicole Bartlett, NOAA)

About 2 months ago NOAA announced MRIP, the Marine Recreational Information Program, was officially in place.  MRIP introduces a new way of collecting and analyzing recreational data in order to reduce bias and improve accuracy of recreational fisheries data.  While the full program was years in the making and a complete transition will only come after newly collected data is analyzed and included in management, this marks a significant change from previous recreational catch assessment.

MRFSS random digit dialing of coastal households has recently been replaced by a registry, the National Saltwater Angler Registry.  If you have purchased a salt water fishing license in most states, you are already registered, but if you would like to find out for sure, check out your eligibility: National Saltwater Angler Registry.  Additionally, more and even effort has been allocated to the angler intercept surveys to reduce previous bias.  Samplers have less choice in their sampling sites and are now required to sample for a prescribed amount of time.  Finally, some of the statistical improvements will be made to the catch and effort data before they are made available for use.

Recreational fishing is big business in the US, and improve management benefits everyone. (Photo: Andrew Schmidt)


While the improved accuracy in recreational fishing estimates will benefit nearly all involved, for those of us on the academic side of fisheries science it helps to know that the fisheries data we use from NOAA is continually improving the confidence we have in our conclusions.  NOAA has even run some comparisons of MRFSS data when adjusted for the new MRIP analysis and those revisions can be queried here (from the Catch or Effort Data dropdown menu, select "MRFSS/MRIP Comprison").  Finally, you can check out the MRIP program here.

Always remember that the ultimate limiting factor in this elaborate survey program is the data source—that means you!  If you are selected to participate in a phone or dockside interview, please consider contributing your information to the program so that the best possible descriptions of the fishery can be used to manage our common resources.

Steve Midway



No comments:

Post a Comment

Please leave a professional comment to create discussion about this topic. We reserve the right to remove any comment.