Scientists and advocates are raising alarms about the potential impact of non-native species on the overall health of the Great Lakes.
On Wednesday, researchers from Cornell University and the U.S. Environmental Protection Agency announced the discovery of two new non-native species of zooplankton that were found in western Lake Erie. The findings came as part of a long-term biology monitoring program that collects samples from 72 stations across all five Great Lakes twice a year.
Taxonomists at Cornell’s Biological Field Station in New York analyzed the zooplankton samples and confirmed the two new non-native species: the cladoceran Diaphanosoma fluviatile and the copepod Mesocyclops pehpeiensis.
The finding means that four non-native zooplankton have now been identified in the Great Lakes in just the past few years. All four of have been found in western parts of Lake Erie.
In a statement, Molly Flanagan, vice president of policy at the Chicago-based nonprofit Alliance for the Great Lakes, called the discovery “concerning news.”
“The fact that these are the third and fourth non-native zooplankton found in Lake Erie in the past three years is an alarming trend,” she said.
According to Cornell’s report on the discovery, Diaphanosoma fluviatile is native to South and Central America and the Caribbean. The species has been sighted in Florida, Louisiana and Texas, but its presence in Lake Erie “marks a dramatic northward expansion for the species,” researchers said.
Mesocyclops pehpeiensis, the other newly discovered non-native species, is native to temperate and tropical parts of Asia, and has been reported in Mexico, Cuba and the southern U.S.
Researchers said that both of the species can be difficult to distinguish from native species, which look similar. Cornell taxonomists were able to identify the new species with the help of two global experts on the species, Kay Van Damme and Janet Reid.
According to the U.S. Fish and Wildlife Service, the threats posed by the two species to the Great Lakes remains uncertain and requires more analysis. Cornell researchers said they will continue to work with scientists from USFWS and EPA to further assess the risk posed by the species.
“While we may not yet know how these two new species entered the Great Lakes, we do know that once in the lakes aquatic species are easily moved from lake to lake by ships,” Flanagan said in a statement. “As a result, a new non-native species in one Great Lake pose a potential risk for the entire region.”