On Tuesday evening, Maryland Department of Natural Resources (DNR) released updates to the state’s oyster stock assessment that revealed the overall oyster population in Maryland waters increased due to recent boosts in oyster productivity. The abundance of market-sized oysters, those larger than 3 inches, was the second highest observed since 1999, with the highest concentrations found in the Choptank River region.
Despite this positive news, DNR noted that nine areas of the Bay continue to experience overfishing, harvesting at unsustainable rates that, over time, could lead to the decline or loss of oysters in those regions. This is an uptick from the 2021 assessment which indicated that four regions of the Bay were experiencing overfishing at the time. In addition, five regions are considered depleted, with the lowest oyster population levels recorded since 1999.
The stock assessment found that overfishing was continuing to occur in Tangier Sound, on the lower Eastern Shore. More than 90% of the 2022-2023 public oyster harvest was pulled from just 10 harvest areas in Maryland, with more than 60% coming from Tangier Sound and the lower Patuxent River alone.
In response, DNR officials put forth a proposal which would maintain the current oyster fishing regulations, pending the results of the upcoming fall oyster dredge survey which estimates oyster productivity and survival annually. This in-season management approach would be new for Maryland where oyster fishery regulations typically have not changed from year to year.
DNR must finalize the new management options prior to July 1.
The new assessment results come after scientists have recorded two years of above average spat set for oysters, which have improved the overall oyster abundance in the Bay. However, the increased abundance of oysters attracted increased fishing pressure, resulting in the two largest oyster harvests in the past 35 years. In the 2022-23 season, watermen harvested 620,000 bushels of oysters from public fishing areas, which was the largest recorded harvest since the 1986-87 season when watermen harvested 976,000 bushels.
Even with recent gains in oyster abundance, the number of oysters in Maryland’s portion of the Bay remains at a small fraction of the population before industrialization in the late 1890s.
CBF’s Maryland Executive Director Allison Colden issued the following statement in response to the stock assessment update:
“The dramatic increase in oyster harvests during the past two years comes as no surprise after several record years of oyster reproduction. We’ve seen this pattern before – without adequate controls on fishing effort, increases in the oyster population are quickly followed by increases in harvest and then declines in years where environmental conditions are less conducive for oyster productivity. Unfortunately, these boom-and-bust cycles undermine the long-term recovery of the species, by wiping out years of good productivity with increased harvest.
“However, fishing effort has not increased uniformly across the Bay. Of concern is a significant increase in fishing effort on Maryland’s most productive public oyster grounds, including Tangier Sound. In this region, the assessment indicated overfishing occurring for more than three years.
“Our best available science indicates that fishing rates like those seen in Tangier Sound, St. Mary’s, and the lower Patuxent River, are not sustainable. We are encouraged that DNR has proposed a more responsive approach to oyster management, based on the fall dredge survey, and urge them to consider further regulations that aim to end overfishing in the regions where it is occurring.
“It is critical to protect the oyster population gains made from strong spat sets during the past three years if we are to reverse the long-term trajectory of oyster decline. Oysters are a vital component of the Bay ecosystem that filter water and provide habitat and nursery grounds for fish and crabs. Despite the recent increases in oyster abundance, the current population remains far below levels needed to deliver these critical ecosystem functions.”
