Fishery-Independent Surveys: Critical Utility in Stock Assessments, and So Much More…

Fishery independent survey data have been a cornerstone of fishery stock assessments for over four decades.  In some regions of the country (and especially the developing world), however, the capability to conduct such surveys have heretofore been severely limited by expertise, availability of ships and other infrastructure, and the lack of an institutional structure to deal with the results of such surveys.  Under the Magnuson Stevens Fishery Conservation and Management Act Reauthorization of 2007, the mandates to produce annual catch limits (ACLs) for all stocks as well as assessments of overfishing/overfished status have put even more demands on an already underfunded and understaffed system.  That being said, the incremental addition of finding through NOAA’s “Expand Fishery Stock Assessments” initiative resulted in measurable progress towards the goals of indexing all significant fishery stocks.  Notwithstanding this progress, however, Congress needs to fund these programs commensurate with the requirements of the 2007 reauthorization of the Act, if it expects to achieve the stated goals of rebuilding all overfished stocks by 2015. 

The meaning and scope of fishery-independent surveys have changed dramatically over the four decades during which they have been conducted.  Originally and primarily conceived as relative indices of population abundance and recruitment, used in tuning dynamic pool population models, many survey programs have since evolved to produce direct estimates of fishery abundance and biomasses.  Such efforts provide a valuable check on the results of population modeling (sanity check) and as well can produce more timely results if data processing and analysis systems are equally developed.  The advent of large-scale areas closed to traditional sampling methods (e.g., trawling) or the incompatibility of these gears with hard bottom habitats have resulted in the exploration of new technologies including acoustic, photographic and telemetric methods.  The use of these methods will expand especially if they can be demonstrated to be cost-effective.  Beyond their utility in stock assessments, fishery-independent survey data have also evolved to be a critical data source in understanding impacts of climate change on the distribution and abundance of marine species, in regulatory analyses and for understanding critical habitat-distribution linkages.