North Dakota officials say an invasive mollusk has reached the waters of a major state lake.

North Dakota officials say an invasive mollusk has reached the waters of a major state lake.

WDAY-TV reports Sunday that officials at Lake Ashtabula have confirmed they have an infestation of zebra mussels.

The state's Department of Natural Resources says the small mussels reproduce quickly and consume the food sources needed by the lake's natural fish population. It makes the water appear clearer but it disturbs the lake's ecosystem.

Area Fisheries Supervisor Nathan Olson says zebra mussels eat parts of the food chain needed by other small organisms and fish.

Zebra mussels have been in North Dakota waters since 2015 and in Minnesota Lakes for about 10 years.