For the fifth year in a row, Chesapeake Bay oyster reproduction in 2024 was higher than the 39-year median, according to the Maryland Department of Natural Resources’ annual Fall Oyster Survey.2023 was a “remarkable year” for baby oysters, with the number of spat per bushel being almost four t imes greater than the median over the previous 39 years. Although the 2024 spat index was lower than 2023, it was still above the long-term median. The spat recorded in 2023 grew into “smalls” by 2024, continuing the positive trend of oyster population growth. Despite lower salinities stunting the growth of these oysters, scientists observed little mortality. 2024’s wet start also helped diminish disease levels among oysters.“The 2024 Fall Survey confirms Maryland’s oyster population is doing well, with the key indicators showing encouraging results,” said Christopher Judy, Director of the Department of Natural Resources Shellfish Division. “Certain low salinity regions still need to improve, but overall the findings are promising for the near-term future of this vital species.“Salinities were elevated in 2023 due to drought conditions, which contributed to the highly successful oyster reproduction that year. But higher salinities can also support the parasitic disease MSX, which in 2023 expanded its reach as far north as Hacketts Point near the Bay Bridge, as well as throughout many of the Bay’s tributaries. Also in 2023, another parasitic disease called Dermo rose above the long-term average for the first time in six years.However, consistent rains from December 2023 through May 2024 provided relief from elevated salinities and, in turn, from the Dermo and MSX parasitic diseases. The survey found that 17 out of the 26 samples that have been completed had no sign of MSX, while the highest prevalence of the disease among the remaining completed samples was 7%.Salinities climbed again in mid-2024, supporting that year’s spatset. DNR conducted the 2024 fall survey from Oct. 8 to Nov. 25 in oyster-growing waters of Maryland’s section of the Chesapeake Bay and its tributaries, including the Potomac River.During this period, biologists collected 364 samples from nearly 300 oyster bars. Of these, samples were collected from 95 oyster bars within 38 sanctuaries.Scientists even observed a small number of spat north of the Bay Bridge, which is rare.The highest natural spatset of the survey was found in an experimental crushed concrete planting in Pocomoke Sound. However, the lower third of the Potomac River reverted to modest spatsets, and no spatsets were observed above that third. ...read more read less