Jonah Crab

The Jonah crab is a marine crab species that lives in the waters off the eastern coast of North America. It is valued for its sweet and flavorful meat and its claws and legs, which have a more affordable price than other types of crabs. It has a rough-edged carapace with yellow or light spots and dark-tipped claws. This Northwest Atlantic crab is closely related to the European brown crab in the Western Atlantic.

5 Jonah Crab Facts

• Jonah crab recipes call for steaming or boiling, after which the meat is removed from the body, claws, and legs.
• Because Jonah crab meat is less expensive, it is often mixed with Dungeness crab or blue crab meat.
• The Atlantic crab species is related to the Dungeness crab of the Pacific.
• Its geographic range is from Newfoundland, Canada, to Florida.
• The name “Jonah” refers to the biblical character Jonah, who was swallowed by a whale, and is often associated with bad luck.

Classification and Scientific Name

The Jonah crab’s scientific name is Cancer borealis. It’s also called a white legger. It belongs to the genus Cancer (meaning “crab” in Latin) or coastal crabs, along with the Atlantic rock crab (Cancer irroratus). The class Malacostraca contains the largest number of the six classes of crustaceans, including crabs, lobsters, crayfish, shrimp, krill, prawns, and woodlice. The order Decapoda (decapods) contains shrimp, lobsters, crayfish, and prawns, while the family Cancridae is a family of crabs with six existing genera. The genus Cancer of marine/coastal crabs contains eight existing species, including the red rock crab and the European edible (brown) crab. “Cancer” means “crab” in Latin, and “borealis” means “north.” The name “Jonah” refers to the character Jonah in the Bible, who was swallowed by a whale, and refers to bad luck. In the fishermen’s case, the presence of Jonah crabs means that there are no lobsters in the net because the Jonah crabs eat the lobster bait.

Appearance

Jonah crabs are first measured by their carapace, which indicates their weight. Males reach a width of 8.74 inches for the carapace, while females reach no more than 5.9 inches. The typical weight for their carapace size is as follows: A Jonah crab with a carapace measuring 5 inches in width weighs 12 to 14oz, 5.5 inches weighs 15 to 16oz, and 5.75 inches weighs 18 to 19oz.

Distribution, Population, and Habitat

The Jonah crab’s geographic range is from Newfoundland, Canada, to Florida. Its main locations for landings are Prince Edward Island, the Gulf of Maine, and Rhode Island, with habitats being coasts with rock, clay, sand, and mud. It lives in depths of up to 2,461 feet but usually 164 to 984 feet, and has a preferred average temperature of 59.7 °F.

Predators and Prey

The Jonah crab’s diet is carnivorous. Its prey is smaller animals, especially crustaceans and gastropods. They are scavengers when necessary and so sometimes also eat carrion.

What do Jonah crabs eat?

Mussels (especially blue mussels), arthropods, snails, and certain species of algae, which are neither plants nor animals.

What eats Jonah crabs?

Seafood-eating birds of prey, such as seagulls, eat Jonah crabs. So do otters, alligators, sharks, rays, and bony fish. Humans also eat them.

Reproduction and Lifespan

When the carapace reaches the width of 5 inches for male Jonah crabs and 3.5 inches for females, they can reproduce. They reproduce by spawning and do so between late winter and early spring. A female crab lays one egg clutch per year or up to five broods per lifetime. Each clutch carries between 160,000 and 1,000,000 eggs. She lays her eggs in soft substrates for warmth and safety. The gestation period is 9 to 14 days. Female Jonah crabs move closer to the shore during the late spring and summer and then go back offshore in the fall and winter.

Recent research suggests Jonah crabs can take 4 to 9 years to reach harvestable size in the wild, indicating a longer lifespan than previously thought. Specific maximum lifespan data is still limited.

Fishing and Cooking

Jonah crab can be used in any recipe that calls for crab meat. The recipes call for steaming or boiling the crabs, then removing the meat from the claws and legs. The price is more affordable than Dungeness, stone, or blue crab. It is sweet with a darker and heavier texture than Dungeness crab, flaky, but firm like Florida stone crab when cooked right.

This particular crab is popular in New England, especially Massachusetts and Rhode Island, and is managed cooperatively by the Atlantic States Marine Fisheries Commission (ASMFC) and individual states. Federal waters remain largely unregulated. Typical recipes for Jonah crab include:

• Steamed and served chilled over ice
• Crab cakes
• Crab stock
• New England crab stew

Nutrition-wise, the Jonah crab is a great source of protein and has trace amounts of iron and calcium. It is low in calories and fat.