Officials from the Maryland Departments of Natural Resources, Environment and Health and Mental Hygiene gathered at the Magothy Marina in Anne Arundel County to discuss details of ongoing fish kills in two Chesapeake Bay tributaries. The shallow creeks and coves, or sub-tributaries, of the Patapsco and Magothy Rivers in Baltimore and Anne Arundel Counties continue to experience fish kills that officials primarily attribute to severely depleted dissolved oxygen levels. The Maryland Department of the Environment estimates that more than 200,000 fish have been affected since the events began last week.

"These fish did not have lesions or any other type of anomaly," said Charles Poukish, environmental specialist for MDE. "It's important to note that this problem is the result of drought-associated conditions, not Pfiesteria."

Affected areas of the Magothy River include Cocky Creek, Cattail Creek, Little Magothy Creek and Deep Creek. Bear Creek, Colgate Creek, the Inner Harbor, Marley Creek, Furnace Creek, Stony Creek, Rock Creek, Old Road Bay and Bodkin Creek have been affected in the Patapsco River. All fish species commonly found in these areas have been affected, including menhaden, silversides, perch, mummichogs, pickerel, catfish and sunfish. The majority of the fish involved have been young, 2 to 3 inch fish.

"Drought conditions have probably allowed algal blooms to proliferate in the upper ends of creeks, which often receive large amounts of nutrient runoff," said Robert Magnien, chief of Resource Assessment for the Department of Natural Resources (DNR). "When this algae dies, or stops producing oxygen during daylight hours, oxygen can drop to lethal levels."

Fish need adequate amounts of dissolved oxygen to survive. Recent dissolved oxygen levels in these areas have been near zero. Typical levels would be in the 5 to 8 parts per million (ppm) range; fish begin to struggle for oxygen when levels fall below 5 ppm. DNR water quality crews have intensified monitoring of water conditions.

"It's likely these conditions will persist until we receive steady rain and cooler weather for more than several consecutive days," added Magnien.

According to the Maryland Department of Health and Mental Hygiene, the following public health guidelines apply in the presence of a fish kill:

• Do not swim in areas experiencing a fish kill.
• Do not eat fish that are dead or dying when caught.
• Know what healthy fish look and smell like (scales and skin intact, fresh sea breeze scent, clear eyes, not slimy).

To report a fish kill, contact the Maryland Fish Health Hotline at 1-888-584-3110.