Leaving no stone unturned in the search for invasives
A cool, crisp morning greeted volunteers for the Bridge Snapshot project Saturday, Sept. 13. The Bridge Snapshot was a cooperative effort by Oneida County Land and Conservation, The River Alliance and the Wisconsin Headwaters Invasives Partnership. Michelle Sadauskus, AIS Coordinator for Oneida County Land and Conservation stated the River Alliance was spearheading the project with the help of a grant from the DNR and asked for assistance of other groups.
“When the River Alliance asked for assistance with the Bridge Snapshot, we were more than happy to jump on board,” Sadauskus said. “We were really interested to see what might be taking place in the thoroughfares between the lakes, in the areas where invasives might be easily introduced.”
In essence, the goal of the Bridge Snapshot was to determine what, if any, invasives were present in the waters and on the shorelines directly under and near highway bridges. According to Sadauskus, while lake organizations and others do a good job in monitoring the lakes, the junctions between the lakes had not been looked at as closely. In areas near and around bridges there is an opportunity for invasives to be spread in a variety of ways. They can be introduced by people walking or wading into the water, by launching boats there, or even from vehicles driving over on highway bridges.
The biggest problem with invasive species is they are often quite prolific growers. They can be likened to dandelions growing in a lawn. While the homeowner may want a rich, lush lawn, the dandelions oftentimes can take over if left unchecked. The same can be said for invasive plant species. The two sets of species the Bridge Snapshot looked at were aquatic and terrestrial. While plant species can grow and spread quickly and change the fragile ecosystem of a river or lake, many invasive animal species have no known predators. This means their numbers, too, can grow quite quickly. Not only can the lack of predators be a problem, but these species are then competing for the same food sources of other, native, aquatic animals. This is a big cause of concern for many residents and other stakeholders of area waters.
Three teams of volunteers headed out to inspect the areas around various bridges in Oneida County. Rosie Page from the Wisconsin Headwaters Invasives Partnership met Rhinelander volunteers at the Rhinelander District Library Saturday morning to explain the protocols to be used and to divide up the bridges to be studied. Page explained the wet and dry protocols to the volunteers and how to go about collecting samples of suspicious terrestrial and aquatic plants. She also asked volunteers to take pictures of any invertebrates they suspected to be targeted invasives. One concern voiced by a few volunteers was that some of the growing seasons for some of these plants were coming to a close. That concern was validated to some degree in the field, but even then enough evidence of the invasive plant species remained for volunteers to make a positive identification.
The volunteers followed a very specific protocol when they arrived at their bridge sites. In those areas where it was not too dangerous, volunteers waded into the water of the Wisconsin and Pelican Rivers near the highway bridges. In other areas they did their research from shore. They first looked over the area and took pictures, noting any possible invasives. If any suspect terrestrials were present, a sample was placed into a sample bag. The volunteer then recorded as much information as possible about the area the invasive covered and any other details. Then volunteers raked the bottom of the rivers to pull up plant matter and any woody substances. Those were then inspected for invasive species. Where possible, the volunteers also used their hands or a scoop to collect substrate and sift through it for any invertebrates that could be found. If any were found, they would carefully take pictures of them rather than try to bring them back to the check point at noon. Dan and Marj Mehring were a couple of the volunteers. They live Squash Lake west of Rhinelander, where Invasive Eurasian Milfoil has recently been found.
“That’s the reason we’re here,” Dan Mehring said. “Eurasian Milfoil was found in Squash Lake, where we live. So, this is just a subject that’s very near and dear to our hearts. That is why we wanted to be a part of this project.”
Going in, Sadauskus, Page, and other team members were hoping to see no new invasives in the bridge areas throughout the county. They were already aware of what the volunteers might find at these locations, but were eagerly awaiting the results by lunchtime on Saturday. They expected Purple Loosestrife, some invasive thistle, and a few of the other more common invasive species. It is difficult enough to control the known invasives and if the volunteers were to find new issues, that would only expand that problem.
Once all of the volunteers brought in their findings, the results were studied, as were the plant specimens that were brought in by the volunteers. Rosie Page stated that she was very excited to see that no new invasive species were found. The Rhinelander volunteer group had a good laugh about Bob Martini’s most invasive of all species that he found near the Highway 17 Bridge on the Wisconsin River. He found a rubber duck that escaped from Potato Fest two weeks prior. While they joked about the little yellow duck, it did help to illustrate how something someone does in one part of a waterway can have effects in a much larger area.
In Rhinelander, the bridges studied were the Highway 17 Bridge on the Wisconsin River and two bridges on Highway 8 over the Pelican River. The bridge over the Wolf River on Highway B was also studied by the Rhinelander group. The team confirmed the presence of Purple Loosestrife at the Wisconsin River site. The two areas near the Pelican River were found to have invasive thistle as well as Spotted Knapweed, which Grace stated is very common in the area. Only Spotted Knapweed was found near the Highway B Bridge over the Wolf.
Grace and Sadauskus were both relieved to see no new species and only those which they suspected to be at those entry points to area rivers. Grace mentioned that next year, when the Bridge Snapshot is performed again, they will have baseline data with which to compare next year’s findings. Everyone involved was excited to see so much interest from area residents. When it comes to a problem such as invasive species, both aquatic and terrestrial, the more people who are involved and how help to educate others about the problem, the more successful eradicating invasives can be.