Blue crabs, beautiful and graceful swimmers, provide a delicate, sweet flavor for any seafood lover. Traditionally, the year-round population of Long Island Sound blue crabs found themselves near the northern limit of their range. However, global warming has provided them an opportunity to increase their numbers in our warmer waters, while the Sound’s cold-water dependent lobster populations have suffered a huge decline. According to Connecticut Sea Grant, following the 1999 lobster die off, New York and Connecticut commercial landings of lobsters dropped by as much as 99%. Even declines in fish species such as winter flounder have been attributed to increases in the Sound’s water temperatures.
Along our Atlantic and Gulf of Mexico coasts, blue crabs have long been sought-after by recreational and commercial fishermen. The crustaceans are the most valuable fishery in Chesapeake Bay where male crabs prefer Maryland’s tidal fresh water, and females inhabit the saltier Virginia waters, closer to the ocean. They are also one of the most important seafood harvest in the Gulf of Mexico where Louisiana, during the season, is said to land about 26% of the Nation’s blue crabs.
The crustaceans have a varied diet. They feed on fresh dead fish, worms, clams, mussels, oysters, small soft-shell blue crabs and even some marine plants such as eelgrass. They in turn are prey for some shore birds, large fish such as striped bass and sea turtles.
The crabs live up to 3 to 4 years. As they grow, they shed (molt) their outer shell. The new shell, which can be about 30% larger than the old one, is soft (soft shell crab). The new shell gradually hardens over 3 to 4 hours. Over their lifetime, females molt 18 to 20 times, while males do so 21 to 23 times.
Blue crabs with their brightly colored blue to olive green shells have three pairs of walking legs with additional rear legs that are equipped with broad swimming paddles. They walk rapidly across the bottom but using their paddles, they swim sideways as they seem to scoot away. Mature males have bright blue claws while females’ blue claws have red tips. Closely related to blue crabs, the Sound’s lady crabs (= calico crabs) are also equipped with paddles that allow them to swim.
The year-to-year population of Long Island Sound’s blue crabs fluctuates a great deal according to the water temperature. When subjected to severely cold winters, their numbers can plummet. Those inhabiting shallow water are particularly susceptible. To avoid the colder water, some migrate to deeper water and burrow into the sediment. When the summer waters get too warm, as they did in 2012, hypoxia (loss of oxygen) can occur, causing die-offs.
In the Sound, male and immature females generally inhabit less saline areas such as tidal areas near a river’s mouth or small near shore bays. They are often found among underwater marine grasses that they use as a food source. Mature females and egg-bearing females generally inhabit deeper, more saline waters.
Between 2011 and 2017, surveys of the blue crab population in the Eastern Sound (Pequannock River, Bakers Cove and Mystic River), showed a marked change in their numbers from one year to the next. However, crabbing has frequently been productive in the lower reaches of the Connecticut River, Brandford River, Oyster River (Saybrook), Tom’s River (Madison) and at other sites. Some are taken in the waters of the Western Sound such as the Housatonic River, Oyster Bay, NY and other sites. There are even reports of successful crabbing in the Hudson River.
Recreational crabbing is a rewarding pastime. Blue crabs are frequently found on mud bottoms, in shallow estuaries, bays and harbors. Near shore, wading in about three feet of water, they can be caught during the day using a long handle, wide mesh scoop net. However, since they are nocturnal, they are often easier to spot and catch after sunset, using the same equipment and a narrow-beam flashlight. If a light shines directly into their eyes, like lobsters they bolt away. But once caught, they can be put in a large plastic pail that is well attached to a small inner tube. The rig is easily towed by the crabber. Boat docks, piers and even bridges that cross an estuary are also productive sites.
Crabbers also use a baited handline and a dip net. Bait is tied to a length of line and dropped to the bottom. Favorite baits include oily fish such as mackerel, herring and bluefish or raw chicken necks. Raw chicken wings are also popular. The line goes tight when a crab begins to check out the bait. Slowly bring it in and scoop up your catch with the dip net.
Collapsible and non-collapsible crab traps are also popular. Baited with oily fish or chicken parts, the blue crab crawls into the trap, attracted by the bait. The state authorities have different rules for setting recreational non-collapsible crab traps. Be sure to check their sites.
Scuba diving for crabs is easy enough, but their sharp claws can be a hazard to your fingers! During the day, they can be spotted under rock ledges and sometimes partially buried in the sediments. They are however, more active after dark. Equipment should include thicker Scuba gloves, a shore handle net and a catch bag. If possible, grab one by the top and bottom rear part of its shell. They can also be taken by gasping both claws at a time. Watch your fingers and enjoy your catch!
In Connecticut, open season for blue crabs runs from May 1 through November 30. In New York waters, open season is year-round. Neither state requires a license for the recreational capture of blue crabs. In Connecticut, hard shell crabs must be 5 inches wide, point to point – soft shell, 3.5 inches. In New York waters, hard shell crabs must measure 4.5 inches – soft shell 3.5 inches. Taking egg-bearing females is strictly prohibited in all states. Be sure to check each state for changes in their regulations.