New Guidance on Calibrating MRIP Catch Estimates

Stock assessment scientists looking to incorporate the recently re-estimated MRIP catch numbers into their analyses have new guidance from NOAA Fisheries. Final reports from the Calibration Workshop and resulting Ad Hoc Working Group are now available on the MRIP website.

As reported in the last issue of Newscast, NOAA Fisheries in cooperation with SEDAR hosted a Calibration Workshop. The purpose of the workshop was to develop a method to adjust catch estimates derived from the old MRFSS with the more accurate estimates produced using the improved MRIP methodology. One of the outcomes of the workshop was to create an Ad Hoc Workshop Group, which was charged with:

Establishing a priority list in each region for which species assessments should be updated to incorporate the new MRIP-derived catch estimates; and

Providing a technical approach (or approaches) to hind-casting and forecasting catch estimates.

The working group ranked the species based on the differences between MRFSS and MRIP catch estimates and the relative importance of the recreational catch time series in the overall assessment model. The report includes the criteria and overall rankings for each species by region.

For their second charge, the working group determined that a "ratio of means," which would look across all of the comparison years, instead of a "mean of ratios" for individual years, would be the most effective basis for a ratio estimator. The report includes more details about their technical approach as well as guidelines for using the ratio estimator.

The ultimate goal of both reports is to help managers and scientists most effectively use the re-estimated recreational catch estimates in stock assessments and fisheries management. For more information, please contact Dave Van Voorhees at dave.van.voorhees@noaa.gov.