Part C: Gone Today, Here Tomorrow?
Fishery management's job of stock assessment is difficult in part because fish aren't stationary creatures, like trees, but because they also live underwater. Fishery managers have had to determine best practices to formulate stock assessments and how to develop catch quotas and limits.
1. Read the following excerpt from NOAA's 2018 Report to Congress on the status of US Fisheries to better understand how NOAA tracks U.S. fish stocks.
Fishery management plans must specify objective and measurable criteria (reference points) to determine when a stock is overfished or subject to overfishing. A scientific analysis of the abundance and composition of a fish stock, as well as the degree of fishing intensity, is called a stock assessment. Stock assessments are subject to regional peer review as part of the process to ensure that management decisions are based on the best scientific information available. In fiscal year 2018, NOAA Fisheries conducted 198 stock assessments.
The councils and the agency use information from stock assessments to develop and recommend ACLs and other conservation and management measures. While catch limits are set annually, assessments are often done less frequently. To determine whether catch limits have successfully ended or prevented overfishing, NOAA Fisheries may use the fishing intensity metrics and reference points derived in a stock assessment or a comparison of catch to the overfishing limit (OFL). If the catch-to-OFL comparison is used, an overfishing determination is made annually. If a stock assessment is used, due to timing of the next stock assessment, several years may pass before we are able to determine if catch limits successfully ended overfishing.
Rebuilding Plans for Overfished Stock
Any stock that has previously been listed, or is currently listed, as overfished is required to have a rebuilding program until the stock has been rebuilt to levels consistent with supporting MSY on a sustainable basis. In many locations, such as Georges Bank, this rebuilding plan includes the establishment of Marine Protected Areas.
Beginning in 1994, three large areas totaling 17,000 km2 in Georges Bank were closed to fishing for groundfish. Fishing gear that might catch groundfish incidentally or damage habitats were prohibited, but other forms of fishing such as long-lining were allowed to continue. Additional fishery management measures such as groundfish fishing permit limitation, increase of trawl mesh size, and reduction of groundfish fishing time were also applied. By 1999 there was a 40% reduction in fishing by trawlers, but other forms of gear and fishing for species other than groundfish is still allowed in the areas.
2. Watch this brief video showing scientists taking a trawl assessment and performing other data gathering on the fish and habitat in a closed area on Georges Bank.
Scientists did find an increase in groundfish biomass in closed areas. Haddock rebounded well and the stock was considered rebuilt in 2010. However, cod around Georges Bank, and in the whole of the Northwest Atlantic, remained overfished and overfishing continued during a number of years even with the closures in place.
3. The Gulf of Maine Research Institute issued a report in June 2013 titled The Future of Cod in the Gulf of Maine. Read Section 1. Understanding Environmental Change (Acrobat (PDF) 386kB May21 20). (Note: Section 1 begins at the bottom of the first page.)