Describe life on Chesapeake Bay, and it’s hard not to say something about the iconic, ill-tempered blue crab. Whether it’s picking a mess of spicy, steamed crabs or frying up a Maryland-style crab cake for the perfect sandwich, the blue crab has been a reliable source of pleasure for locals and visitors alike, not to mention its economic impact on the region.Of all the Bay’s species, it has proved the most resilient in the face of habitat loss, pollution and overfishing.
So when eager recreational crabbers and professional watermen headed out to traditional Chesapeake Bay hot spots this year to find a virtual blue crab desert, people began to worry. In the past, most anyone with a few hours and some patience could rustle up a couple dozen crabs for dinner, even during lean years. But this season, many crabbers pounded the water for hours, only to return home with empty bushel baskets. Commercial crabbers with hundreds of crab pots in the water also reported grim conditions.
So what happened, and why is it so troubling? Though no one is completely sure, folks with decades of Chesapeake crabbing under their belts can’t remember ever coming home without a single crab. It simply has never happened. Even when populations of the Bay’s two other keystone species — oysters and striped bass — collapsed in past decades, crabs could still be relied on to satisfy both commercial and recreational interests. Today, folks are asking: If blue crab populations are on the brink, what does that say about the health of the Bay?
The benchmark tool for assessing blue crab populations in Chesapeake Bay is the annual Blue Crab Winter Dredge Survey. It aims to estimate the total population of blue crabs by dredging up and counting the crustaceans during the only time of year they’re stationary: during the winter, when they hibernate in the muddy bottom of the Bay. Biologists sample more than 1,500 sites and come up with an estimated total blue crab population, including breakdowns by segments such as spawning-age females and juveniles. From those numbers, fisheries managers in Maryland and Virginia can make targeted management decisions aimed at increasing declining portions of the blue crab population.
Although numbers over the last two decades have had noticeable peaks and valleys, it’s the last seven years that have been among the most volatile. In 2007, after holding an average Bay-wide population of 318 million between 2000 and 2006, crab numbers dipped to 251 million in 2007, the lowest in the survey’s history. When 2008 survey numbers failed to rebound at only 293 million crabs, the U.S. Department of Commerce declared the Chesapeake blue crab fishery a federal disaster, clearing the way for more than $10 million in federal funds designed to help struggling watermen and further management efforts.
Both Maryland and Virginia immediately focused on enacting regulations designed to rebuild the overall crab population — more specifically, to increase the number of spawning-age females. In Maryland, the recreational harvest of female crabs was banned, new size limits were put in place, and periodic seasonal bans and bag limits were placed on the commercial female blue crab harvest. Perhaps most celebrated, however, was when Virginia closed its winter crab dredge season for the first time in its history. The fishery was often criticized because it focused on dredging up post-spawn female crabs that winter in the Lower Bay. These are the females that would normally go on to disperse their millions of fertilized eggs in the spring if left unharmed.
If Winter Dredge Survey numbers are a reputable management yardstick, the new regulations were a complete success. By 2010, the total count of Chesapeake blue crabs had increased to 663 million — the highest since 1997. Although numbers dipped in 2011, to 452 million, the population jumped again, to 765 million, in 2012, seemingly marking a complete recovery of the fishery. Many remember Maryland Gov. Martin O’Malley standing in front of a local crab house and declaring a victory in blue crab management. But the celebration was short-lived.
The 2013 numbers were devastating. The number of spawning-age females had increased to a healthy 147 million, but the overall blue crab population had plummeted to 300 million, the lowest since 2007. But given the healthy number of spawning-age females in the Bay, folks hoped for a quick recovery. The bottom dropped out when the 2014 survey results came in. Not only had the population dipped again — this time to 297 million — but the total population of spawning-age females had fallen to 69 million, below the minimum safe threshold of 70 million.
When people returned to the water and found crabs almost completely absent, panic set in. Local outdoor writers called for an all-out ban, perhaps hoping that crabs might recover as striped bass did after a six-year moratorium in the ’80s. Conservation groups demanded tighter regulations on the commercial harvest of females, and a group of Virginia watermen even asked for better crab-management solutions. That’s telling of the situation, given the independent nature of these strident souls. Although Maryland recently launched a “Don’t Get Pinched” campaign to target the illegal harvest of blue crabs in hopes of preserving the crabs that remain, neither it nor Virginia have proposed new harvest regulations … yet.
When crab numbers are in decline, you can count on one thing: a handful of wildly varying explanations as to what happened. After the devastating 2007-2008 numbers were released, some blamed an overly healthy population of striped bass for devouring the crabs. A similar theme played out in 2013, when fisheries managers and scientists pointed to a huge influx of crab-loving redfish as a reason for the decline. Other scientists point to the blue crab’s highly cannibalistic nature for one particular year’s poor numbers. So what did scientists blame the poor 2014 number on? They cited the unusually harsh winter and a resulting die-off.
We won’t know whether the Chesapeake Bay blue crab can make a comeback as it has in the past, but one thing’s for sure: All eyes will be focused on the results of the 2015 Winter Dredge Survey when it is released next spring. Until then, the future of this resilient crustacean is anyone’s guess.
October 2014 issue