A bighead carp has been seized by a local fisherman in the Minnesota river, representatives of the Department of Natural Resources have announced on Wednesday, February 24.
The giant fish, weighing about 25 pounds, was found and harvested close to New Ulm, by a commercial angler who had been in the area in order to try and nab buffalo fish and common carp.
The bighead carp was a male, and it is believed that it reached Minnesota’s waterway after migrating upstream from the Mississippi river, according to Nick Frohnauer, river habitat coordinator and invasive fish expert at Minnesota’s Department of Natural Resources.
The journey appears to have extended across 120 miles, probably debuting close to Minneapolis-Saint Paul. As biologists speculate, it’s likely that the bighead carp was either foraging for food or searching for other members of the same species, and that’s how it traveled so far, eventually stopping at New Ulm.
This is thought to be the second time that an Asian carp has been encountered in the area in recent months, another similar capture involving a grass carp being reported back in December, 2015.
Asian carps were initially imported from China back in the 1970’s, because they were considered to assist the aquaculture sector, by removing algae from commercial ponds.
However, they soon managed to escape their former enclosures, reaching Minnesota in the 1990’s. Now the presence of these large aquatic creatures in the Gopher State’s waters is particularly problematic because they have been proven to be an invasive species, which can severely disrupt the local ecosystem.
That’s because they tend to feed excessively on zooplankton and phytoplankton, therefore depriving mussels, forage fish and other native aquatic creatures of these microorganisms, which represent essential food sources. The more they grow, they also pose a threat to larger fish species as well, causing a sharp decline in their numbers.
For now the discovery of this new bighead carp doesn’t appear to indicate that the large predators have chosen the Minnesota river as breeding grounds as well, or that they have already settled in the region.
Even so, wildlife experts are still concerned about the dangers posed by these voracious invaders, and several initiatives have been launched in order to impede Asian carps from entering the waterway and wreaking havoc to native fish species.
For instance, experts from Aquatic Invasive Species Research Center (affiliated with Minnesota State University, Mankato) have been collaborating with the state’s Department of Natural Resources with a view to identify regions that might be chosen by Asian Carps as mating grounds, and to investigate the distribution of flood plain areas.
New stretches of water allow invasive fish to spawn more frequently, and to swim between rivers, lakes creeks and swamps which hadn’t been linked under normal circumstances.
Researchers are also looking into ways to set up barriers that would halt the migration of Asian carps to the Minnesota River.
The Upper St. Anthony Falls Lock and Dam has already been shut down in June, 2015 by the U.S. Army Corps of Engineering, with the very same aim of impeding invasive carps from spreading even further.
Such endeavors along the Minnesota River are hampered by the fact that the waterway tends to be quite wide, and prone to flooding, but barriers could be placed in connected areas, such as Madison Lake.
It is expected that feasible solutions will be devised and conclusions will be reached by December 2017, when a report will have to be submitted to Minnesota’s Department of Natural Resources.
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