Those thresholds are tied to commercial harvest, and do not include the harder-to-measure recreational crab harvest (which was estimated to be 7% of the total in 2010). In 2012, the Chesapeake Bay Program Sustainable Fisheries Goal Implementation Team defined a minimum "exploitation level" at 25% of the estimated female abundance, and a threshold for overharvest was set at 34% of that population. After the 2007 population crash, the old measure (46% of the total crab population) was replaced with a new sex-specific measure: protect 70 million adult female crabs over the winter as a minimum, with a target population of 215 million spawning-age female crabs. Scientists have used different measures of sustainability. Secretary of Commerce declared an economic disaster, providing some funding to mitigate the impacts on the local watermen and processors. Crab-related employment declined 40% between 1998-2006, though bay-area processing houses imported crabs from Louisiana as an alternative supply source. The decline of crab harvests from the high of 113 million pounds in 1993, to a low of 49 million pounds in 2000, led to a parallel decline in jobs. Source: Chesapeake Club and Friends of the Rappahannock It should be steamed and eaten with Old Bay and melted butter - helped build support for water quality controls that will help "Save the Bay" in places far from the bay itself.Īdvertising to create support for stream buffers in the Shenandoah Valley emphasized a key benefit of the Chesapeake Bay for people who live far away from the shoreline Highlighting the tasty blue crab - No crab should die suffocating in oxygen depleted water. Sediment damaging the habitat of the blue crab comes from places far upstream, including the Giles County (headwaters of the James River near the West Virginia border) and Augusta County (headwaters of the Shenandoah River near Staunton). Overharvest and habitat destruction by crabbers are not the only causes of population decline. Oyster dredging and other fishing practices scalped the bottom of the bay, physically ripping up the SAV beds in the same way an all-terrain vehicle can convert a productive pasture to into a mud bog.
The Submerged Aquatic Vegetation (SAV) habitat of the blue crab declined by 50% after 1960, as sediment blocked light from penetrating the water in the Chesapeake Bay. In the prior 10 years, the harvest level had averaged 62% of the population, far beyond sustainable levels. In 2007 the population crashed, and in 2008 Maryland and Virginia cut the harvest by 1/3. In 1948, there were 60,000 crab pots in the Chesapeake Bay, but that number expanded over the next 50 years to a million.
Scientific research indicates that 46% of the total crab population could be caught annually, but the harvest exceeded that sustainable level. The population decline was caused by two factors: over-harvest and reduction of suitable habitat. Striped bass and other fish depend upon blue crabs as a key part of their diet, while crab larvae provide food for various filter feeders such as menhaden and oysters. The blue crab is a keystone species, fundamental to the ecology of the bay. Economically, the blue crab harvest has provided the highest value of any Chesapeake commercial fishery, but after a record harvest in 1993 the population declined substantially. The name indicates why managing this particular species is so important to those trying to restore the Chesapeake Bay. The scientific name of the blue crab, Callinectes sapidus, means "beautiful swimmer - savory." Two of its 10 legs are modified into swimming paddles, and another two are pinchers desired for defense and grabbing food. Source: National Oceanic and Atmospheric Administration (NOAA), Habitat Conservation Blue crabs are an iconic symbol of the Chesapeake Bay
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