Thousands of dead fish and crabs floated to the surface of the Magothy River this week, suffocated by low oxygen levels in the water.

Waterfront homeowners and boaters reported the dead fish - perch, bluegill, pickerel and carp as well as dead crabs - Wednesday and Thursday.

The Maryland Department of the Environment sent investigators to the site of the fish kill, centered on Blackhole Creek on the north shore of the river.

They're testing fish tissue and water samples for toxic algae or other culprits, but their working hypothesis is that weather conditions led to an unexpected lack of oxygen in the water, said Dawn...