Results from the 27th Bay-wide Winter Dredge Survey, conducted from December 2015 to March 2016 (Attachment I) by the Virginia Institute of Marine Science and Maryland Department of Natural Resources, indicate the blue crab stock is not depleted and overfishing is not occurring. The 2015-2016 Winter Dredge Survey estimates of abundance of all size classes of crabs was 553 million crabs, and this total abundance represents a 35% increase from the 2014-2015 Bay-wide Winter Dredge Survey and is above the long-term (1989-90 – present) average of 458 million crabs. The most recent abundance of juvenile crabs enumerated from this winter survey was 271 million, and is slightly greater than the long-term survey average of 262 million juvenile crabs. The importance of the juvenile crabs surveyed in wintertime is their contribution to the following late summer and fall harvest when they have recruited to harvestable size and their contribution to the subsequent year’s late May and July-August spawning periods. The number of overwintering female crabs that could potentially spawn (if not harvested prior to the spawning seasons) in 2016 was 194 million. This was an improvement over the 2014-2015 survey estimate of 101 million and was above the threshold and about 10% below the management target of 215 million overwintering female crabs. Additionally, 194 million potential spawners is above the long-term average of 118 million potential female spawners. The importance of the mature female crabs is their contribution to the spawning events in late May and July – August of the same year the Bay-wide Winter Dredge Survey is completed. These crabs also are important to the spring and early summer harvest, as a high proportion of the Virginia commercial and recreational harvests consist of female crabs.
Year-to-year variation in abundance of blue crabs can be expected as a result of the effects of environmental influences, especially for early life stages of crabs. Juvenile crab abundance can vary because of inter-annual difference in entrainment of crab larvae from the ocean to the Virginia portion of Chesapeake Bay that is subject to prevailing current and wind patterns. Environmental factors including weather conditions and predation can have an effect on all life stages of the crab population. Conservation of female spawning-age and juvenile crabs is the primary management objective to attempt to lessen variability of the blue crab stock abundance. Since 2008, there has been a continuation by all Chesapeake Bay jurisdictions of management measures that conserve the spawning-age female crabs. The number of spawning-age female crabs, estimated in 2016 as 194 million, increased 92% from the 2015 estimate of 101 million. This increase may be partly attributed to management measures, as fishery managers from the three Chesapeake Bay jurisdictions enacted spawning conservation measures to protect a portion of female spawning-age crabs and increase spawning stock potential by reducing the harvest of all crabs by 10%. This reduction in harvest for all blue crabs not only protects spawning-age females, but also protects some juvenile crabs that will contribute to the 2016 spawning stock. These jurisdictions also have relied on a new management framework for the past two season in which the fishery is regulated from July through July. The benefit of this approach is that two Bay-wide winter dredge surveys can be accomplished in that 12-month period, and adjustments to conservation measures can be implemented after either survey is complete.
In 2016 the Commission essentially maintained management measures implemented in 2015. VMRC remains cautious concerning variable abundance of blue crab from year to year. Just two years ago, the low abundance (68.5 million) of spawning-age female crabs indicated a depleted stock, as an abundance below the threshold of 70 million spawning-age female crabs is considered depleted. Before any substantial liberalization of current management measures concerning the blue crab occurs, the stock needs to stabilize at an annual abundance that consistently approaches the 215 million spawning-age female crab target. This management framework allows conservation of spawning-age female blue crabs in the spring prior to spawning and a portion of juvenile female crabs for the next year’s spawn. Maintained measures include reduced crab pot bushel and vessel possession limits for specific time periods and a season closure for all other crab gear. The reduced crab pot bushels limits extend from July 5, 2016 through July 4, 2017 for all crab pot license categories. The Commission also closed the winter crab dredge fishery season for ninth consecutive season to allow for continued rebuilding of the spawning stock biomass.
Virginia crab and oyster industries that benefitted from disaster relief funds initially provided in 2008 by the Department of Commerce for the declared Fishery Disaster in Chesapeake Bay blue crab fisheries continue to benefit today. The 2008 Disaster Relief Fund has provided various crab industry members (harvesters, buyers, and processors) negatively impacted by poor crab stock conditions during many years, through 2007, a source of employment. These funds have provided an opportunity to work in resource or habitat enhancement projects. The total amount of funding from the Disaster Relief Fund was $14,995,000. All of the six project areas detailed in previous reports have been completed as of 2014.
Two projects currently supported by the Virginia Institute of Marine Science’s Fisheries Resource Grant Program focus on the commercial crab fishery. One of these, an effort to prevent juvenile flounder bycatch in crab pots, is in its second phase. The other project is directly focused on reducing mortality of blue crabs during the molting stage of soft crab production.