A Virginia state task force is looking into the deaths of hundreds of fish in Peninsula waters in recent weeks.
An algal bloom harmful to humans and animals was found in one creek where dead fish were found, and Department of Environmental Quality spokesman Bill Hayden said Thursday that officials are trying to find out whether it was connected to kills in nearby waters.
However, he said officials believed gill nets were responsible for the deaths of menhaden in the Poquoson River, Back River and Queens Creek.
Reddish water is an indication of algal bloom activity, and it was present in the Taskinas Creek area March 25, a Health Department statement said. Test results from the James City County creek showed a high concentration of a type of pfiesteria, an organism that can be present in algal blooms and can be harmful to humans and animals.
The readings at the mouth of the creek the runs through York River State Park were "the highest we've ever seen in Virginia," said Frank Daniel, regional director of the state Department of Environmental Quality.
However, readings Wednesday were normal, Hayden said.
As a precaution, the park closed Taskinas Creek to fishing and boating until it receives more information from state health and environmental experts, said Brad Thomas, the park's chief ranger.
Biologists found pfiesteria-like organisms in the East River in Mathews County, but Hayden said there was no indication that the organism was responsible for the fish kill there.
The high concentration of pfiesteria in Taskinas Creek prompted the Chesapeake Bay Foundation to call for the state to act immediately to reduce pollution in state waters.
"Past outbreaks of pfiesteria in the Chesapeake Bay region ... have occurred in waters heavily polluted by nitrogen and oxygen," Jeff Corbin, CBF's deputy Virginia director, said in a statement.
Health Department spokesman Larry Hill said algal blooms usually occur in warmer water. "What's unusual is the time of year it's doing it," he said.
Some scientists believe that pfiesteria killed fish and sickened humans exposed to the waters of the Pocomoke River in Maryland in 1997.
The state task force investigating the cause of the fish kills includes members from the Virginia Institute of Marine Science, the DEQ and Old Dominion University, as well as the Health Department.