Terrells Island and Samers Bay – Habitat Restoration

Fox-Wolf Watershed Alliance (Fox-Wolf), Butte des Morts Conservation Club (BDMCC), Winnebago County (WC), and the Wisconsin Department of Natural Resources (DNR) partnered on a large-scale restoration project to improve water quality and habitat in Lake Butte des Morts. The project team secured over $1 million to fund the project that broke ground in January of 2021. Construction is anticipated to be completed in winter of 2024 (depending on ice conditions). This project will restore ~680 acres of wetland and aquatic habitat.

The restoration has two main objectives:

1. Protect, preserve, and restore ~111 acres of wetland and aquatic habitat on the the north west side of Samers Bay on Lake Butte des Morts.
2. Improve water quality and habitat across 569 acres within Terrell’s Island on Lake Butte des Morts.

To meet those objectives, the project was broken down into two funding phases:

Phase 1:

• Remove a 1,400 ft section of existing rock along the east side of the Terrells Island breakwall (reduced from the original plan to remove ~2,200 ft).
  • This will create a large opening to improve water circulation and re-connect the area with the larger lake 
• Remove rock from five artificial rock islands located within Terrells Island (Islands 2 thru 6).
• Re-use rock removed from Terrells Island to build ~3,000 ft. of a new breakwall along the north west side of Samers Bay.
  • To protect an area that is eroding, on average, at a rate of 8 to 9 ft. per year.

Phase 2:

• Complete construction of the remaining 2,850 feet of the Samers Bay breakwall.
  • This will create a calm, protected area to re-establish aquatic vegetation.

In summary, when the project is complete, Terrells Island will have a 1,400-foot opening on the east side of the existing breakwall. The rock material removed to create the opening will have been used to build a large portion of the new Samers Bay breakwall. This opening will allow for substantial water exchange between the area inside of Terrells Island and Lake Butte des Morts. The result will be better water quality and reestablished use by desirable fish and wildlife species within the 569-acre Terrell’s Island Habitat Restoration Area. The Samers Bay breakwall will total 5,850 feet in length (~5,200 ft of breakwall with 35-foot openings every 500 ft.) and will restore 111 acres of wetland habitat.

The Butte des Morts Conservation Club, WI DNR, and Winnebago County LWCD held two public meetings regarding proposed habitat restoration efforts at Samers Bay and Terrell Island on Lake Butte des Morts. Both meetings were well attended with attendees expressing support for the projects.

CLICK HERE to view the slides from the presentations.

In addition to public meetings, the restoration project has been highly publicized through press releases, local postings, social media, newsletters, websites, and more. Overall, projects partners have received positive feedback with stakeholders acknowledging that the water quality improvements and increased opportunities for wildlife viewing and nature enjoyment will far outweigh changes being made to the existing structure.

Habitat and Water Quality

A key component of these restoration projects is the re-establishment of aquatic vegetation. Breakwalls provide conditions perfect for aquatic plant growth by:

• Reducing the re-suspension of lake sediments which improves water clarity.
• Creating calm areas protected from the turbulent waves of the large, shallow lakes.

The restoration of aquatic vegetation within these breakwall projects will provide nesting, spawning, rearing, and refuge habitat for multiple fish species. Fish species including bluegill, crappie, largemouth bass, and yellow perch will likely benefit the most and should utilize the restored habitat throughout the year. The restoration of vegetation will also provide important spawning habitat for adult northern pike and Great Lakes spotted muskellunge as well as provide refuge for juvenile fishes. Fishery surveys have shown that fish diversity and abundance (particularly Centrarchids) increase when aquatic vegetation is restored.

Source: WI DNR

For example, electrofishing surveys were conducted in 2018 to evaluate the existing Clarks Bay breakwall on Lake Winneconne. Three stations were surveyed to assess fish abundance and population metrics including, the inside of the breakwall along the structure, outside the breakwall along the structure, and a station to the east of the breakwall with natural shoreline. Catch rates for largemouth bass, bluegill, and yellow perch were notably higher inside the breakwall (64.4, 135.6, and 113.3/mile) compared to the natural shoreline station (12.0, 16.0, and 54.0/mile). In addition, bluegills were observed spawning along the rocks on the outside the breakwall along the structure, with a catch rate of 177.1/mile for the station. Therefore, the restoration of aquatic vegetation within new breakwalls should help to continue restoring fish populations.

Wildlife beneficiaries include furbearers, migratory waterfowl, coots, rails, wading birds including American and least bitterns, Foster’s and black terns, bald eagles, and ospreys.  Of particular interest is the potential to re-establish migration habitat for diving ducks such as scaup, redheads, and canvasbacks, all of which formerly visited the Winnebago pool Lakes in large numbers during spring and fall migrations.

This project will also reduce the nutrient loading from loafing birds inside Terrell’s Island.

Recreation Benefits

In addition, improving fish and wildlife habitat at Samers Bay and Terrell’s Island will provide better recreational opportunities for the public, including fishing, hunting, canoeing, kayaking and wildlife viewing.

These efforts would help to meet the original goals of the Terrell Island property management plan, including:

• Protection of Lake Butte des Morts and the Winnebago Pool Watershed;
• Protection and restoration of the plant communities and fish and wildlife habitat;
• Allowing public access for recreational purposes.

Learn more at the Butt des Morts Conservation Club’s website: CLICK HERE

This multi-agency and stakeholder project helps the system progress toward habitat restoration and water quality improvement goals outlined in several agency management plans, such as:

• Winnebago Waterways Lake Plan
• Winnebago County Land & Water Resource Management Plan
• Winnebago County Water Quality Improvement Program
• North American Waterfowl Management Plan
• Upper Mississippi River and Great Lake Region Joint Venture – Implementation Plan

What are off-shore breakwalls?

Off-shore breakwalls are a line of rock riprap located in open water parallel to the shoreline typically adjacent to eroding wetlands. Learn more about breakwalls here: CLICK HERE

Project updates:

Breakwall Installation – Phase 1
Photo Collection