Rising tides can also affect coastal towns. Sea-level-rise destroys the wetlands and shores along the Chesapeake. Finally, rising sea levels also threaten the Bay. Additionally, climate change has led to more severe storms, which dump high amounts of eroded soil and polluted runoff into the Bay more soil and chemicals in the water affect oxygen levels in the water, which in turn harms the Chesapeake’s crabs, fish, and plants. Warmer water damages the eel grass, the plant where the blue crabs make their homes. Geological Survey, average stream temperatures in the Bay have increased by 1.1☏ over the last 60 years. Rising temperatures due to greenhouse emissions harm the Bay’s ecosystems. Climate change, too, has contributed to a reduction in the blue crab population. By 2000, the Chesapeake Bay’s crabs only accounted for 28% of the country’s crab harvest. In the 1980s, crabs from the Chesapeake Bay accounted for over half of crabs harvested in the United States. This activity pushed more people onto the water as a result, blue crab populations decreased. Additionally, in the 1950s, recreational crabbing became popular. The incorporation of the crab pot into the crabbing business led to a dramatic increase in harvests. This technology allowed fishermen to harvest a substantial amount of crabs in one catch. In 1943, Marylanders started using a new tool: the crab pot. Fishermen were taking too many female crabs out of the waters too fast, and there was not enough time for the crab populations to reproduce. LOC.īut with this interest in crabs came harm to the aquatic populations in the Bay. Juvenile crabs rely on abundant underwater grasses to hide from predators, and on thriving oyster reefs to find food.Fisherman’s boat with crab net. “In some kind of way, she worked out for us,” he said.Ĭhris Moore, the Chesapeake Bay Foundation’s senior regional ecosystem scientist, said blue crabs have probably benefited from steady improvements in the bay’s health at large. Brown, president of the Maryland Watermen’s Association, said he was glad to see such restrictions “paying off for a change.” Plus, he added, Mother Nature was kind to the crabs. For example, watermen cannot catch male crabs less than five inches across from April through Jul 14, and 5¼ inches from July 14 through Dec. Hesapeake Bay Foundation officials called the results encouraging, but also not surprising, and urged officials to maintain strong limitations on the crab fishery. In the annual crab survey, Maryland Department of Natural Resources and the Virginia Institute of Marine Science dredge up crabs, count and measure them before releasing them back into waterways at 1,500 sites throughout the bay from December through March. That year, juveniles numbered a record 587 million, while the population totaled 765 million in all. The crab population hasn’t been larger in the bay since 2012. It was the second year in a row of strong growth in the juvenile crab population, from some of its lowest numbers of the past three decades in 2017. That’s what happened during the winter of 2018, when a third of adult crabs in the bay died while hibernating in the mud.īut ahead of the 2019 crabbing season, which began April 1, currents helped send a surging number of larval crabs up the bay, from their birthplace at the mouth of the Chesapeake. Weather and current patterns can significantly help or hinder the spawning of a new generation of crabs each year, and cold temperatures can kill many crabs during the winter. The blue crab population can be notoriously fickle, challenging efforts to balance conservation and commercial harvest. “The blue crab population is both healthy and thriving, which is great news for the entire Bay,” Natural Resources Secretary Jeannie Haddaway-Riccio said in a statement. The results suggest a strong crabbing season is ahead for Chesapeake watermen, with strong numbers of adults ready to be harvested as waters warm this month and a booming crop of young that could grow large enough to be legally caught by the fall, or the 2020 crabbing season. “The female abundance of blue crabs is close to our target, and the juvenile population is above average,” Michael Luisi, fisheries monitoring and assessment director for the Maryland Department of Natural Resources, said in a statement. With a total of nearly 600 million crabs in the bay, the species is close to or above benchmarks that indicate a healthy and sustainable population. The number of spawning-age females, a key measure of future population growth potential, reached 190 million, a 29 percent increase over the previous winter. Scientists in Maryland and Virginia found that the bay’s crabs are at their most plentiful in seven years. There are nearly twice as many juvenile crabs in Chesapeake Bay waters as there were a year ago, according to an annual population survey.
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