The Bioeconomic Impact of Different Management Regulations on the Chesapeake Bay Blue Crab Fishery

Abstract

The harvest of blue crabs Callinectes sapidus in Chesapeake Bay declined 46% between 1993 and 2001 and remained low through 2008. Because the total market value of this fishery has declined by an average of US $ 3.3 million per year since 1993, the commercial fishery has been challenged to maintain profitability. We developed a bioeconomic simulation model of the Chesapeake Bay blue crab fishery to aid managers in determining which regulations will maximize revenues while ensuring a sustainable harvest. We compared 15 different management scenarios, including those implemented by Maryland and Virginia between 2007 and 2009, that sought to reduce female crab harvest and nine others that used seasonal closures, different size regulations, or the elimination of fishing for specific market categories. Six scenarios produced the highest revenues: the 2008 and 2009 Maryland regulations, spring and fall closures for female blue crabs, and 152‐ and 165‐mm maximum size limits for females. Our most important finding was that for each state the 2008 and 2009 scenarios that implemented early closures of the female crab fishery produced higher revenues than the 2007 scenario, in which no early female closures were implemented. We conclude that the use of maximum size limits for female crabs would not be feasible despite their potentially high revenue, given the likelihood that the soft‐shell and peeler fisheries cannot be expanded beyond their current capacity and the potentially high mortality rate for culled individuals that are the incorrect size. Our model results support the current use of seasonal closures for females, which permit relatively high exploitation of males and soft‐shell and peeler blue crabs (which have high prices) while keeping the female crab harvest sustainable. Further, our bioeconomic model allows for the inclusion of an economic viewpoint along with biological data when target reference points are set by managers.

Management Evaluation for the Chesapeake Bay Blue Crab Fishery: An Integrated Bioeconomic Approach

“…The Chesapeake Bay is the largest source of blue crabs in United States, accounting for about 50% of the nation's blue crab harvest (Miller et al 2011). Economically, blue crab is the largest commercial fishery in Chesapeake Bay (Miller et al 2011) with a market value of US$46-103 million annually (Bunnell et al 2010).…”

“…Currently the crab fishery is closed from November or December until March or April of the following year, depending on jurisdiction. In recent years, the management strategy has leaned towards protecting female crabs using a shortened season and short within-season closures for female crabs (Bunnell et al 2010;Miller et al 2011). Size limits vary by jurisdiction, season, and market category.…”

“…The model, which is represented in Figure 1, has three main components. First, we used the individual-based simulation model of Bunnell et al (2010) and Bunnell and Miller (2005) to predict the policy effects on an age-structured population and the harvests of each of the five market categories. Each individual in the model represented a "superindividual."…”

An evaluation of the synchronization in the dynamics of blue crab (Callinectes sapidus) populations in the western Atlantic

“…Economically, blue crab support important commercial and recreational fisheries in many Atlantic estuaries (Bunnell et al 2010). As a result, management agencies along the eastern United States have collected fishery-independent and fisherydependent data on crabs within their corresponding jurisdictions over a long period of time.…”

Sex Ratios and Average Sperm per Female Blue CrabCallinectes sapidusin Six Tributaries of Chesapeake Bay

“…Several authors have suggested that the blue crab Callinectes sapidus is one species in which this occurring (Hines et al 2003;Jivoff et al 2007;Ogburn et al 2014). The blue crab supports one of the highestvalued commercial fisheries in Chesapeake Bay, with exvessel landings valued at around US$73 million annually (Bunnell et al 2010). Declines in harvest in the 1990s and 2000s caused concern about recruitment overfishing.…”