FRANKLIN — Now that cold weather has finally dissipated a several-month-long blue-green algae bloom, Lake Carmi is contending with another threat: alien invaders.

Local birdwatching enthusiasts Hal and Charlotte Bill discovered hundreds of unusual dead fish on the boat ramp of the Lake Carmi State Park on Saturday. They’re small fish, only a few inches long, and a plain silver, like living lures.

Investigation by the Vermont Department of Fish and Wildlife (VTDFW) soon discovered those hundreds were only a small portion of a lake-wide fish kill numbering in the thousands.

VTDFW has now confirmed Charlotte’s suspicion: that the dead fish were, in fact, alewives, a dreaded non-native invader that has plagued Vermont lakes since the late 1990s.

Alewives are three-and-a-half to six-and-a-half inches long, but they have a large effect on native fish populations.

Shawn Good is a VTDFW fisheries biologist out of the department’s Rutland office. He spotted a post about Charlotte’s discovery on the Save Lake Carmi Facebook page, and began investigating.

Good explained alewives are such aggressive feeders they can outcompete native fish populations for food. They will even prey on larval native fish, which has a significant effect on native fish populations. Worse still, alewives are as aggressive breeders as they are eaters.

For more on the alewives and their possible impact on Lake Carmi, pick up a copy of Wednesday’s Messenger or subscribe to our digital edition.