Zebra mussels have been found in the Waupaca Chain o’ Lakes and are probably reproducing, according to an aquatic invasive species specialist with the state Department of Natural Resources.
Brenda Nordin with the DNR’s Northeast Region said about a dozen mussels of various sizes were found attached to a cinder block in the Chain’s Long Lake in May.
“That tells us they’re probably reproducing and they’ve probably been here for two years,” she said. “The Chain has a really good boat inspection program, so I was kind of surprised that they were able to get through.”
Zebra mussels are tiny clams that can grow as big as 2 inches long, but are typically under an inch. They feed by drawing water into their bodies and filtering out most of the suspended microscopic plants, animals and debris for food. This process can lead to increased water clarity and a depleted food supply for other aquatic organisms, including fish. The higher light penetration fosters growth of rooted aquatic plants which, although creating more habitat for small fish, may keep larger, predatory fish from finding food.
This thicker plant growth can also interfere with boaters, anglers and swimmers. Zebra mussel infestations may also promote the growth of blue-green algae, since they avoid consuming this type of algae.
Once zebra mussels are established in a water body, very little can be done to control them.
The mussels most likely entered the Chain attached to a boat, but could have also come from pier installation equipment, Nordin said.
“They can attach to weeds on a boat,” she said. “A lot of people don’t even know they’re spreading them.”
This isn’t the first time zebra mussels have been found in area waters. According to the DNR, they have also been confirmed in Waupaca County’s Partridge Lake and the Wolf River in 2005; Waushara County’s Gilbert Lake in 2009, Silver Lake in 2006 and Long Lake in 2002; and Shawano County’s Cloverleaf Chain in 2009 and Shawano Lake in 2001.
Wisconsin lakes and rivers are better protected against aquatic invasive species, but the confirmation of zebra mussels and Eurasian water-milfoil in new waters in 2009 underscores the need for boaters, anglers and others to continue taking steps to prevent the invaders from spreading.
“New laws, more local partners and good awareness of the prevention steps give us a stronger foundation to keep new invaders out and control the spread of the invaders that are already here,” said Jeff Bode, longtime leader of the DNR’s lake protection and aquatic invasive species control programs.
“The key is for boaters and anglers to be vigilant about taking the required prevention steps,” he said. “There are more waters with invasive species this year and that means more opportunities for people to accidentally spread the invaders if they are not careful.”
Those steps generally require boaters and anglers to avoid moving water, plants, fish and other organisms from one lake or river to another.
While boaters and anglers have long been advised to clean off their boats before leaving the landing, a new law prohibits boats from leaving the launch dirty.
It is illegal for people to drive away from a boat landing with aquatic plants or animals attached to their boat, trailer or vehicle. A first citation of this so-called “transporting” law carries a penalty ranging from $232 to $767.50 and a second offense within three years carries a penalty that ranges up to $2,657.
DNR conservation wardens and specialized deputy wardens known as Water Guards will make traffic stops of vehicles travelling on public highways and observed to have aquatic plants or zebra mussels attached to the vehicle, boat, trailer or other equipment.
They will issue warnings and educating people about the new law, Water Guard Mac Hannon said.
“We will be stressing education over enforcement,” he said. “While citations may be issued in some cases, our goal is to get all boaters to voluntarily follow this law in order to protect Wisconsin lakes, rivers and fish.”
Wisconsin’s new invasive species rule, which took effect Sept. 1, 2009, classifies invasive plants and animals as “prohibited” or “restricted” and sets regulations for each category, has been working, according to Bode.
“The new rule has allowed us to respond quickly to contain early introductions of new invasive like the red swamp crayfish, yellow floating heart and Brazilian water weed,” he said. “We can get on it by engaging the local community and working quickly to try to eradicate it if possible.”
The rule allowed a response last fall when red swamp crayfish, a destructive, invasive crayfish found for the first time in Wisconsin in two Germantown ponds, and when the yellow floating heart was found in two stormwater ponds near Lake Delavan in Walworth County. DNR staff were able to work with local officials to rapidly develop and carry out control plans.
Another new rule, effective this February, regulates the ballast water of large oceangoing ships. Ballast water is the main source of new invaders to the Great Lakes.
The number of local partners working on controlling aquatic invasive species continued to grow in 2009, bolstered by a second year of increased state prevention and control grant money available to communities. The DNR expects to award nearly $4 million this year in grants in 2010, roughly the same amount provided last year to counties, tribes, universities, lake groups and other eligible recipients.
“We’re excited about the growing awareness and active participation by local partners,” said Bob Wakeman, who coordinates aquatic invasive species control efforts for DNR. “Without these local partners and a dedicated corps of volunteers, aquatic invasive species would be even a greater struggle to contain.”
More than 30 county and regional partners now have staff coordinating their efforts to prevent and contain the spread of invasive species. In addition, the corps of dedicated volunteers who spend their weekends and holidays educating boaters or conducting plant surveys continued to hold steady and play a vital role in education, boat inspection and monitoring waters for new invaders. Volunteers accounted for 70 percent of the hours spent on boat inspections statewide in 2009.
Despite these efforts, the number of waters with invasive species continued to grow at a pace similar to recent years. Twenty-two new waters were found to have Eurasian water-milfoil and 10 were confirmed as having zebra mussels. Spiny water fleas were found in the Madison chain of lakes, representing the third inland occurrence in Wisconsin.
The silver lining: quagga mussels, the more damaging cousin of zebra mussels, did not spread inland from Lake Michigan, nor did round gobies. Testing also did not find any inland sites where fish had viral hemorrhagic septicemia (VHS), although the virus that causes the disease was confirmed in fish from Lake Superior, where it had been suspected because it is connected to waters where VHS had already been found.
? The state Department of Natural Resources contributed to this report.