Add additional nodes to the template to complete your concept map.Ĭhesapeake Bay Blue Crab Concept Map Starter TemplateĪfter you’ve given it a try, click “Show Example” to see if you’re on the right track. 1750 Forest Drive Suite 130 Annapolis, MD 21401. You may use a blank sheet of paper or download the concept map starter template below. The Chesapeake Bay Program is a unique regional partnership that has led and directed the restoration of the Chesapeake Bay since 1983. Finally, use short words or phrases to show the relationship between the details and the main topic or other details. Then add details in boxes that describe how they are special or unique. Start with a box for the main topic: Chesapeake Bay Blue Crabs. Let’s begin a simple concept map about what makes Chesapeake Bay blue crabs unique.įocus Question: What makes Chesapeake Bay blue crabs unique? Chesapeake Bay: Nature of the Estuary, A Field Guide by Christopher P.As you explore the videos, information, and activities in the lesson, you’ll take a deeper dive into how our prized blue crabs make it to your table, and along the way, you’ll complete a concept map to record what you learn about various factors that impact the crab industry.Life in the Chesapeake Bay by Alice Jane Lippson and Robert L.The Chesapeake Bay blue crab population has not been overfished since female-specific management was implemented in 2008.Blue crabs are one of the most important commercial and recreational catches in the Chesapeake Bay. It is one of the most recognizable species in the Chesapeake Bay. Male blue crabs are known as “jimmies,” while mature females are called "sooks." The blue crab is a swimming crustacean with bright blue claws and an olive green shell.The blue crab’s scientific name comes from the Greek words for “beautiful” and “swimmer.”.Few blue crabs live longer than three years. Immature crabs molt several times before they reach maturity, about 12 to 18 months after hatching. Megalopae eventually metamorphose into immature crabs, which look like tiny adults. Megalopae are pushed back into the estuary by wind and tidal currents, settling in key nursery habitats such as seagrass beds and marsh fringes. During their last larval molt, zoea metamorphose into a post-larval form called the megalopa. After four to eight weeks of development in the coastal ocean, the zoea return to the brackish waters of the Bay. Even though they have a large claim to fame, they are not the only crabs that live in the Chesapeake Bay. After about two weeks, larvae are released near the mouth of the Bay.Ĭurrents transport the blue crab larvae, called zoea, out into the coastal waters, where they molt several times as they grow. The Blue Crab is a keystone species, meaning that it serves as both predator and prey and the other creatures living in the Bay region are highly dependent upon their survival. The egg mass darkens as the developing larvae consume the orange yolk. Just prior to the final molt, an immature female crab, known as. Each bright orange egg mass may contain between 750,000 and two million eggs. Blue crabs mate from May to October in the brackish or slightly salty waters of Chesapeake Bay. Males eventually leave to search for another mate, while females migrate to the saltier waters of the lower Bay.Īs they migrate toward the mouth of the Bay, females develop an external egg mass, or sponge, beneath their aprons. After mating, the male continues to cradle the female until her shell hardens. Prior to mating, males will cradle a soft-shelled female in their legs, carrying her for several days while he searches for a protected area for her final molt. This phenomenon is known as a crab jubilee. When the water’s oxygen content is too low, blue crabs have been known to come out of the water and onto the land to escape suffocation. Reproduction and Life Cycleīlue crabs mate from May through October in the brackish waters of the Chesapeake Bay. Like all other critters in the Chesapeake Bay, blue crabs need oxygen to survive. Predatory birds, such as blue herons, and sea turtles are also known to feed on smaller crabs. Predatorsīlue crab predators include large fish like striped bass, Atlantic croaker and red drum. They will even eat more vulnerable soft-shelled blue crabs and small juveniles. Feedingīlue crabs will feed on nearly anything they can find, including clams, oysters, mussels, smaller crustaceans, freshly dead fish, and plant and animal detritus. Mature females have a broad, rounded apron, and immature females have a triangular apron. Males have a strongly tapered abdomen, or "apron," that resembles an inverted T. Its claws are bright blue, and those of mature females feature red tips.īlue crabs have three pairs of walking legs and paddle-shaped rear swimming legs. The carapace has nine marginal teeth on each side the ninth teeth are strong spines. The blue crab's carapace (shell) varies in color from bluish to olive green, and can reach up to 9 inches across.
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