Geese are responsible for the E. coli that has closed the swimming beach at Grand Lake State Park, according to the Grand River Dam Authority.
GRDA spokesman Justin Alberty says an independent lab in Tennessee confirms that the high levels of bacteria contained DNA from geese and perhaps another avian source. The results confirm that neither humans nor cattle are the source of the E. coli, he said.
A news release suggests that recent rains washed the geese waste into the lake as that stretch of shoreline is a favorite nesting area for a large population of the birds.
The beach remains closed after a reassessment of bacteria levels on Tuesday.
Other Grand Lake swimming areas remain open, the releases stresses. They will continue to gather daily samples and keep the beach closed until the bacteria levels return to a safe range.