Viral Disease Causes Significant Fish Die-Off in Michigan's Lake Macatawa

Viral hemorrhagic septicemia (VHS), a disease affecting both fresh and saltwater fish, has been identified as the cause of a significant number of dead and dying fish reported in Lake Macatawa, near Holland in Ottawa County, Michigan, since mid-April, according to the Michigan Department of Natural Resources (DNR).

The die-off has primarily affected freshwater drum, also known as sheepshead, with smaller numbers of gizzard shad and pumpkinseed sunfish also impacted. As the infection progresses, infected fish develop widespread hemorrhages on their body surface and within internal organs, often appearing listless, swimming in circles, and frequently surfacing.

Ed Eisch, DNR Fisheries Division Assistant Chief, noted that the virus causing VHS has been present in the Great Lakes basin since around 2005 and has been found in several Michigan inland lakes, as well as in Lake Huron, Lake St. Clair, Lake Erie, Lake Ontario, Lake Michigan, and the St. Lawrence River in New York.

Visitors to Holland State Park have reported seeing dead fish along the shore within the past week. The DNR expects the die-off to continue as water temperatures rise but believes it is likely winding down and will not have a lasting impact on the lake's fish populations.

The DNR emphasizes that the virus poses no threat to humans or pets that come into contact with potentially infected water. To minimize the spread of VHS, the department urges boaters and anglers to disinfect gear that comes in contact with the water and to clean, drain, and dry boats and trailers when moving between water bodies.