Hostile zebra mussels are still showing up in Christmas Lake in Minnesota even after aggressive treatment to rid the lake of them in 2014. Divers searched the area in April and didn’t see any hostile zebra mussels in their travel around the lake, but now a month later, the divers have found 10 of the hostile zebra mussels in an area right outside the treatment area, according to the Minnesota Department of Natural Resources (DNR).
Zebra mussels come from Eastern Europe and Western Russia and are an invasive species in the Great Lakes area. They first started appearing in the Great Lakes in 1988 and came over from travel in the ballast of ships from these areas. It is very pricey, as well as dangerous for these hostile zebra mussels to appear as they clog up water intakes, cut swimmers’ feet, clog up boat motors, reduce the food supply for native larval fish, cause the growth of too much vegetation and cloud the water, as well as grow onto native mussels and smother them.
Hostile Zebra Mussels Affect Other Local Species, Hard to Kill Off
The 10 zebra mussels found were stuck to native mussels, which is a bad sign since they can smother and kill off the native mussels. None of the hostile zebra mussels were seen in the one acre area of Christmas Lake that was treated in three cycles to kill off the hostile zebra mussels during the travel of the divers.
The zebra mussels aren’t easy to get rid of. The DNR had to employ a biological pesticide called Zequanox, as well as use a special copper treatment, and then use potash. This is only the 3rd time Zequanox has been employed to get rid of the mussels in the US. The Watershed District reported that they were happy to see that no hostile zebra mussels were in the one acre area that had been treated, but were upset that there were a few found right outside of that area. They consider the treatment successful in the one acre area and said that the 10 mussels found could have been attached to the native species of mussels since sometime in the fall or summer of 2014.
Now, the DNR will be studying to see if there is any more need to keep up the treatments or other methods of getting rid of the hostile zebra mussels in Christmas Lake since this is still considered to be a local infestation only.
