Scientists found something strange in the Kalamazoo River in Michigan. A water sample collected along the river tested positive for DNA from an Asian carp, but there are no signs of any Asian carp in the river. Asian carp are an invasive species, harmful to the Great Lakes.
Conservationists collected water samples from 200 points along the river in July. Just one of those samples contained traces of DNA from an Asian carp. The DNA came from a silver carp, one of the four invasive species of Asian carp that threaten the Great Lakes. The sample was found only 24 miles away from Lake Michigan, one of the Great Lakes. This is the first time researchers have seen silver carp DNA in this part of Michigan.
"While we don't have evidence of a live fish in the water, we treat this finding very seriously," said Tammy Newcombe, who works for the Department of Natural Resources.
The DNR plans to collect 200 more water samples from the Kalamazoo River starting today, on Tuesday. The organization said that they will likely have the results of the testing later this month.
It is important for people who live near the Kalamazoo River to watch out for signs of silver carp, and report to their local agency if they think they have found one. There is a guide to spotting Asian carp online. The DNR also plans to increase its monitoring of the Kalamazoo River, and alert local fishermen of the need to stay aware of, and report sightings of silver carp.
The silver carp was first introduced to the United States in 1973 as a means to control phytoplankton. However, the silver carp is very damaging to native species because it competes with some species of fish that are native to the region for plankton. It was declared a harmful invasive species in 2011.
The U.S. Geological Survey has a map detailing all the silver carp sightings on record. This finding is the first potential sighting of silver carp in this part of Michigan (even though no silver carp has actually been seen yet), so local officials are being careful to try to nip this problem in the bud before it spreads even further.
In September, the EPA announced the second half of its ten-year plan to restore the Great Lakes, including control of invasive species.
