First Finding in Winnebago Waterways System

In August a newly verified population of Brittle Naiad (Najas minor) was found in Lake Butte des Morts by Fox Wolf Watershed staff. This is the first finding in the Winnebago Waterways area and the 9th verified occurrence in Wisconsin. At this time, there are only a handful of locations with the plant where the Upper Fox River empties into Lake Butte des Morts (west of Oshkosh). The map to the right marks the locations of where the plant was found.

Brittle Naiad, a prohibited invasive species in Wisconsin, was previously found upstream of Lake Butte des Morts in Lake Puckaway (2013) and Buffalo Lake (2014).

One of the most noticeable and identifiable features of this plant are its leaves that curve strongly downward. The leaves hold their shape and curvature when out of water. Another distinguishable feature of the plant are the spines along the bottom of the leaves. These tiny spines are visible to the naked eye but will not cut or poke you.

The impacts of Brittle naiad vary between invaded lakes and rivers. The plant tends to grow earlier in the year and out compete native plants. There are some cases of naiad reaching nuisance levels and impacting channel navigation. In some lakes, Brittle naiad has been seen to out-compete two other well known invasive plants; Eurasian watermilfoil and curlyleaf pondweed. However, in other lakes, Brittle naiad doesn’t have a significant impact on the lake or natural areas.

The Brittle naiad populations in Lake Butte des Morts were found during sampling efforts being conducted by the Winnebago Waterways Program at the Fox-Wolf Watershed Alliance. A sample of the plant was collected and sent to the Wisconsin Department of Natural Resources for verification.

If you find this plant while out fishing, hunting, boating, or walking anywhere around Lake Winnebago or the Pool lakes, be sure to report it! You can contact Chris Acy, the Aquatic Invasive Species Coordinator at Fox-Wolf. His contact information is listed below this article.

Want to help monitor your lakefront or favorite boat launch for Brittle naiad? Check out our Volunteer Opportunities to protect the places you love!

Information used in this article comes from the Great Lakes AIS Information System Brittle Naiad Factsheet

Photo Credit: Chris Acy, Paul Skawinski

Questions? Comments? Contact Chris Acy, the AIS Coordinator covering Brown, Outagamie, Fond du Lac, Calumet, and Winnebago Counties at (920) 460-3674 or chris@fwwa.org!

Follow the Fox Wolf Watershed Alliance’s Winnebago Waterways Program on our Winnebago Waterways Facebook page or @WinnWaterways on Twitter! You can also sign-up for email updates at WinnebagoWaterways.org.

Winnebago Waterways is a Fox-Wolf Watershed Alliance program. The Fox-Wolf Watershed Alliance is an independent nonprofit organization that identifies and advocates effective policies and actions that protect, restore, and sustain water resources in the Fox-Wolf River Basin.

Check out the Keepers of the Fox Program at https://fwwa.org/watershed-recovery/lower-fox-recovery/