Aquatic Invasive Species

If you suspect a new infestation of an invasive plant or animal...
take a photo and note the location, or save a specimen and report it to our local DNR invasive species contact - Dan Swanson, 218-833-3750
Always inspect your boat, trailer, personal watercraft, and other water related equipment before entering and after exiting the lake.


The latest invasive species with the potential to threaten Lower Hay Lake is Starry Stonewort.  It was first discovered in Lake Koronis (near St. Cloud) in August of 2015, and now covers roughly 250 acres in the lake.  The Koronis Lake Association has allocated $828,000 over the next 3 years to management the current infestation, starting with herbicide treatments.  Unfortunately, complete eradication is unlikely as it has not yet been successful in other states.
Starry Stonewort is a form of algae that has the appearance of a grass-like plant and is not native to North America.  The distinguishing factor in starry stonewort is the presence of star-shaped bulbils.  This invasive plant forms dense mats at the water's surface causing problems with boats, native vegetation and fish.  
In some states, lakes have been completely closed due to starry stonewort infestation.
https://sites.google.com/site/friendsoflowerhay/protecting-our-lake/aquatic-invasive-species/StarryStonewort.JPG

Zebra Mussels were discovered in Lower Hay Lake during the summer of 2013 - found on a rock at the Lower Hay access.  After the 2015 summer season, a number of residence confirmed multiple zebra mussels on dock bases and other water equipment.  

We are aware of current experiments with chemical and bacteriologic methods of zebra mussel extermination, but there is not yet a way to eliminate them on a lake of any size.  

Zebra mussels attach themselves to solid surfaces in the water - including boats and motors.  (Find out how you can protect your boat/motor here).  Adults are 1/4 to 1-1/2 inches long and have D-shaped shells with alternating yellow and brownish colored stripes.
Spiny waterfleas are in nearby Lake Mille Lacs.  
These tiny creatures compete directly with newly hatched fish for the same food supply - plankton.
The bigger fish we like to catch need to eat these smaller fish to grow.  Fewer smaller fish mean the bigger fish will suffer. 
 
Spiny waterfleas may be recognized as a glob of sticky "mucus" gumming up the holes on a fishing rod.  Adults range from 1/4 to 5/8 inch long with a single tail and small spines along its length. The adults and the eggs may also be found in mud on anchors, anchor ropes and lake water.
The Eurasian Watermilfoil plant is found within five miles of Lower Hay Lake.  If it reaches our lake, it likely will come in on the bunk of a boat trailer. 
All it takes is one small stem to float into the lake, root itself and start growing an entire colony.   

Once in a lake, it is virtually impossible to eradicate completely.  Control can be costly to lakeshore owners - most often involving chemical herbicides being put into the lake water. 

Eurasian watermilfoil typically has 12-21 leaflet pairs per leaf.  It can often be confused with a beneficial native plant - Northern watermilfoil - which only has 5-10 leaflet pairs per leaf.