The 2019 Minnesota waterfowl season will be swinging into high gear when the season resumes Saturday after a five-day furlough. As the month of October deepens the chances of spreading aquatic species from infested waters to other lakes are bound to grow.
While fishing boats, jet skis and other watercraft have been targeted by Department of Natural Resources aquatic invasive experts and numerous volunteers since lake ice vanished last spring, the hunting and trapping fraternities are also being given a head’s up now.
“Unfortunately, it only takes one time,” said invasive species specialist Mark Rainweiler of the Minnesota DNR Office in Fergus Falls.
The DNR reminds waterfowl hunters to take precautions against spreading aquatic invasive species. Without the proper precautions, invasive species such as purple loosestrife, zebra mussels, Eurasian watermilfoil and faucet snails can be transported in boats, decoys or blind material.
Invasive species can damage habitat for waterfowl, fish and other wildlife, and can even cause waterfowl die-offs. For example, faucet snails can carry parasites that can kill thousands of ducks.
Faucet snails host three intestinal flukes that can kill scaup (bluebills), coots, and other waterfowl that consume them. Native to Europe, they were first found in the Great Lakes in the 1870s. Faucet snails quickly spread to inland waters, often reaching high densities and outcompeting native snails.
They can spread by attaching to aquatic plants, boats, anchors, decoy anchors, and other recreational equipment.
“They’re spread by the duck hunters themselves,” Ranweiler said.
In the fall of 2007 DNR biologists collected around 3,000 dead bluebills on Lake Winnibigoshish near Deer River. The northern Minnesota lake also lost hundreds of coots during the die-off.
It is believed that bluebill numbers have dropped for a variety of reasons, yet it cannot be argued that interest in Minnesota duck hunting has suffered. Since the end of the 20th century duck stamp sales have dropped more than 25%.
The excitement generated by hunting bluebills has been an unmatched thrill in the past. Their wild, reckless flight and the jet sound generated by their wings have sent shivers down the spines of many hunters in decades past. Bluebills were once the No. 1 diving duck in the bag.
According to Ranweiler, Otter Tail and Grant counties do not have faucet snails problems yet. The nearest lakes infested with the invasive faucet snail are in northern Becker County and Mahnomen County.
Eradicating infestations is nearly impossible.
“After hunting, take a few minutes to clean plants and mud and drain water from duck boats, decoys, decoy lines, waders and push poles,” said Eric Katzenmeyer, DNR invasive species specialist. “It’s the key to avoiding the spread of aquatic invasive species in waterfowl habitat.”
The DNR has the following recommendations to help slow the spread of aquatic invasive species:
• Use elliptical or bulb-shaped or strap decoy anchors.
• Drain water and remove all plants and animals from boats and equipment.
• Remove all plants and animals from anchor lines and blind materials.
• Check compartments or storage in boats or kayaks that aren’t used in rest of the year.
Waterfowl hunters should also remember that they must cut cattails or other plants above the waterline when using them as camouflage for boats or blinds, if they want to move them from lake to lake.
The DNR is also reminding trappers to clean equipment before moving to another body of water.
“Trappers of muskrats and other furbearers should also keep the ‘clean in-clean out’ mantra in mind,” said DNR invasive species specialist Tim Plude. “All traps, lines, boots and waders should be cleaned.”
To kill or remove invasive species seeds or young zebra mussels that are difficult to see, the DNR recommends that boaters use a high-pressure spray or a hot water rinse before launching into another water body (120 degrees for at least two minutes or 140 degrees for at least 10 seconds). Air drying can also be effective but may require more time due to cooler weather.
The Minnesota DNR contributed to this story.