AKWESASNE, N.Y. (WWTI) — A new invasive species has been found in Northern New York. The Saint Regis Mohawk Tribe has confirmed that Eurasian Tench has been found in the Akwesasne area. This was after a fish was caught by a traditional fisherman in recent days.

Eurasian Tench, native to Europe and Western Asia, is considered a globally invasive fish and are currently spreading through the St. Lawrence River, threatening the Great Lakes-St. Lawrence River ecosystems. Tench were illegally released into a tributary of the St. Lawrence River in the 1980s and have spread into the river’s main stem over the past decade.

It is currently found in the Columbia watershed in British Columbia and is well established in the U.S. Mississippi River Watershed. Risk assessments have also indicated that the entire Great Lakes system is vulnerable to a tench invasion because the species forms dense populations and brings threats of non-native parasites.

Along with this risk, biologists and scientists warned of the species’ harmful nature as it competes with other native fishes, degrades water quality, limits submerged macrophyte growth, reduces gastropod populations and promotes the destruction of algae growth.

What does a tench look like?

Tench have dark olive to pale golden coloring, white bronzy belly, and bright red or orange eyes. It has a terminal mouth with a barbel at each corner. It has dark-colored and rounded fins with no spines.

These fish have been documented to grow up to 18 inches in length and weigh 10 to 12 pounds.

What to do if you find a tench?

To control and manage the spread of the invasive species, partners in the North Country are urging anglers to take certain steps if or when they catch a Tench. This includes noting the location, keeping the fish on ice and not releasing it back into the water, and taking up-close photos.

Akwesasne residents should report Eurasian Tench to Jay Wilkins or Tiernan Smith at 518-358-5937. New York residents should report Tench Rob Williams at the St. Lawrence Eastern Lake Ontario Partnership for Regional Invasive Species Management at 315-387-3600 x7724 or rwilliams@tnc.org.