How Does the Rain Affect the Oysters?

They're already wet, but it certainly makes life a little safer for a few of them: Southern Maryland waterway reclassified for shellfish harvesting

The Maryland Department of the Environment has reclassified a portion of the Wicomico River in Charles and St. Mary’s counties for shellfish harvesting. About 2,470 acres of the river have been reclassified from approved to “restricted,” meaning the area is closed to shellfish harvesting.

The change – which is effective today, Monday, November 5 – is due to recent evaluations showing unacceptable bacteria levels in portions of the waterway. The Department of the Environment conducts regular surveys to identify potential pollution sources near shellfish harvesting waters, but the cause of an increase in bacteria levels is not always known and no specific cause has been identified for the increased levels in these areas.

Shellfish are filter feeders with the ability to filter water and get food from microscopic organisms in the water. If the waters have elevated bacteria levels, the risk is greater that pathogens may be present, and this filtering process can then concentrate any disease-causing organisms. Oysters and clams are often eaten raw or partially cooked and must come from waters that are within acceptable bacteria levels.

Actually, the tests are for coliform bacteria, which suggest fecal contamination, which is often increased after a major rain or runoff event. The Bay, and even clean seawater in general, are loaded with bacteria of many types, including some potentially nasty ones, but runoff from sewage and septic systems and pet waste certainly raises the chances for catching something.

The Department of the Environment monitors bacteriological water quality and conducts pollution source surveys to determine which areas are safe for the harvesting of shellfish. The department is required to close areas that do not meet the strict water quality standards for shellfish harvesting waters and it has a longstanding policy to reopen areas to shellfish harvesting when water quality improves.

These actions are necessary to protect public health by preventing harvest from the areas affected and ensure Maryland remains in compliance with the National Shellfish Sanitation Program.

Information on shellfish harvesting areas is available on the department’s website. These designations apply only to the harvesting of molluscan shellfish (oysters and clams); they do not apply to fishing, crabbing or swimming. Consumption advisories for recreationally caught fish and crabs can also be found on the department’s website.

This was before the rains we had over last night and today, so the chances of this clearing up soon seems small.