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Homing in on invasives

About 70 members of dock and lift companies, resort owners, lake associations and others interested in controlling aquatic invasive species gathered Tuesday morning for training -- courtesy of the Minnesota Department of Natural Resources.

Darrin Hoverson, DNR invasive species specialist out of the Itasca office, spoke to the group about aquatic invasive species in area lakes, which ones are in Minnesota, and what needs to be done to prevent -- or at least slow -- their spread.

"The last thing you want is to be known as is the guy who introduced zebra mussel to a lake," he said.

There are many things that can be listed as non-native species, even pheasants for example, but they aren't considered invasive. It's when the species start taking a toll on the ecology, degrading water quality and causing other problems, that they are considered an invasive.

Millions of dollars are spent each year fighting invasive species.

And the No. 1 cause of their spreading is humans -- whether it be intentional or unintentional.

It's the boats, seaplanes, live wells, trailers, docks, bait buckets, waders and shipping industry that transport the invasives from lake to lake.

Some may argue that animals are carriers as well, but Hoverson said, they have a "very, very minimal impact. It's human activity. That is why you need to be diligent when doing your inspections." These creatures are very hard to see at times, he added.

The shipping industry has made improvements over the years, but it hasn't solved the problem of those coming across the ocean, bringing most of these invasives from Eurasia.

Hoverson talked -- and showed examples -- about curly leaf pondweed, flowering rush, zebra mussels, spiny water fleas, faucet snails and viral hemorrhagic septicemia, a deadly infectious fish disease.

All are being found in Minnesota lakes, whether it's in Lake Superior, around the Twin Cities, Rainy River area or Becker County.

Most everyone in the area knows of Detroit Lake's flowering rush infestation and the research being done to help control it.

"Nobody can say it's not a pretty plant, but it doesn't belong in our lakes," Hoverson said of flowering rush.

And zebra mussel has been found in the neighboring area. It was found in Pelican Lake a couple years ago, and many worry it's only a matter of time before it's in Becker County lakes as well.

The veliger is a baby zebra mussel before it has even started to grow its shell. After a female zebra mussel lays about one million eggs a year and they begin to reproduce, the veliger then floats in the water for two to three weeks before it attaches to a surface and begins to take form. It can survive in a drop of water as long as temperatures and oxygen levels are suitable.

"This is what we're very, very worried about when it comes to zebra mussels," Hoverson said.

"It's amazing how fast those things can produce," Nathan Olson, DNR invasive species specialist out of Fergus Falls, said.

Once they are adults, zebra mussels can live in the lake for three to four years. Once out of the water, there are several factors to how long they can survive, including temperatures and humidity.

Leech Lake is the highest priority in terms of lake protection. The most popular lakes in Minnesota are already infected because of the heavy traffic on them, and Leech Lake is one of the most popular that hasn't been infected yet.

But, there are multiple lakes throughout the state that are at a high risk for infestation -- from many of the invasives.

Two of the invasives that haven't spread throughout Minnesota yet but are very dangerous to the fish and wildlife population are faucet snails and viral hemorrhagic septicemia.

With the snails, ducks and coots eat them, and the snails then bore through the birds intestines, causing them to hemorrhage to death.

The VHS, which is invisible, is affecting fish, causing them also to hemorrhage to death.

VHS has had a significant effect on the muskie population near the St. Lawrence River, Hoverson said.

The disease affects over 50 species of fish. Several years ago, there was a documented die-off of muskies, but those that didn't die from the disease were actually left more hardy and fought off the virus.

Like the muskies in St. Lawrence River, VHS "does impact the population but not all individuals will die and will hopefully recover following a die-off," he said.

Not only are watershed districts trying to control the already invaded waters, conservation officers are trying to stop people who are repeatedly disregarding invasives laws.

Hoverson said he was personally involved in a case that went to trial where two bait industry workers "blatantly" illegally took equipment from one lake to another.

The men were fined $3,000 each, a three-year permit revocation and stayed six months jail time, which "basically put them out of business."

"The goal is to stop the movement, not to pinch people, but yes, I've written tickets," conservation officer Traci Hanson said.

The penalties are not overly stiff -- failure to drain a boat or to transfer weeds is $50 each, launch into non-infested waters is $100 to $500, and transporting infested waters without a permit is $200 -- but there is a proposal to double the fines.

"People just aren't seeing the seriousness of it yet," she said of infestations and violations. "The reality is this stuff (invasives not already in the area lakes) is about to be introduced, if it hasn't already."

There is a bill before legislators that will require all lake service workers to go through a training seminar like Tuesday's, pass a test and then pay a $50 fee good for three years. It is very similar to the permit and licensing process for bait providers.

"It got to the governor's desk last year and has a very good chance of passing this year," said Marian Bender, Minnesota Waters.

Minnesota Waters and the DNR have been pairing to give these seminars and training sessions in several locations including Detroit Lakes, Alexandria, Walker, Willmar and Pequot Lakes.

Those who went through one of those training sessions, if the bill passes this year, will be exempt from having to go through the training process again for three years.

She said that Minnesota Waters will be listing all of the lake service providers that went through the training Tuesday as a way to "toot their horns" and make it known that they are concerned about invasives species and are now certified.