Analysis of MRIP Survey Data Files to Distribute Harvest Among Sub-Domains and Estimate Minimum Sampling Levels for Improved Precision of Recreational Harvest Estimates

In Maryland, the Marine Recreational Information Program (MRIP) “inland” area consists of two distinct regions - the Chesapeake Bay and the much smaller Coastal Bays in Worcester County.  Maryland fisheries management and stakeholders agree that some management strategies should be different for these two areas, but it has never been possible to distribute recreational harvest estimates between them.  The MRIP “Survey Data” files were used to distribute harvest (and variance) between the two areas for a suite of ASMFC-managed recreational species including Striped Bass, Summer Flounder and Black Sea Bass.  The relationship between precision and number of angler interview assignments was then investigated for each species.  Although annual harvest estimates for Striped Bass are consistently reported with 15-20 PSE, precision of harvest estimates for other species is poor, especially those caught primarily in the Coastal Bays.  Five times the historical number of assignments were estimated necessary to achieve harvest estimates with 30 PSE for this species complex.  Differential sampling between Chesapeake and the Coastal Bays will minimize the required increase in samples.  The new APAIS design based on 6-hour assignments was implemented in Spring 2013.  If this design change alters productivity (interviews per assignment), these estimates will be affected.