The Nature Conservancy has animated how six invasive species have spread across the Great Lakes over time. The group has created six maps that show population increase and spread since the appearance of each species in the Great Lakes basin and beyond. Sea lamprey, the first of the six invasive species to appear in the area, initially showed up in Lake Erie in 1921. The map shows the population of the fish expanding into the rest of the Great Lakes up until present day. Also included in the maps are Asian carp, zebra and quagga mussels, round goby, Eurasian Ruffe and black carp.
Zebra mussels are one of five aquatic invasive species that The Nature Conservancy has deemed “‘the usual suspects’ doing the most damage in the Great Lakes basin and beyond.”
Originally from Eastern Europe and western Russia, zebra mussels are the only freshwater mussels that can attach directly to other objects. They most likely have come over attached to the bottoms of ships. Once here, the mussels grow in population rapidly. Zebra mussels can produce 100,000 to 500,000 eggs per year, according to The Nature Conservancy. Nicknamed “the Silent Strangler,” these pests smother native freshwater mussels and kill plankton that some fish need to survive.
Native mussels have rapidly declined in the Great Lakes region, casualties of the zebra and quagga mussels brought in the ballast of ships. The foreign mussels attach to the native ones so that they can’t open, feed, breathe or breed.
Scientists have identified a new weapon to ward off two troublesome Great Lakes invaders: A bacterium strain that destroys their guts. It could be an alternative to chlorine and other chemical treatments.
Two funny-named species of freshwater mussels currently found in rivers of the Great Lake states were recently proposed for Endangered Species Act protection.
The rayed bean and snuffbox mussels were recently proposed to be listed as endangered by the U.S. Fish and Wildlife Service. Chemical contaminants, sedimentation, nonpoint source pollution and mining are threats to their habitat’s water quality, according to the service.