It’s National Invasive Species Awareness Week (NISAW) and since we do so much great work to help combat invasive species that improve habitat for birds and people, it is important to continue to raise awareness about invasive species, the threats that they pose, and what can be done to prevent their spread.

Coastal development, climate change, and destructive invasive species threaten the watershed systems that support the great range of bird species in the Great Lakes region. The impacts of climate change are already compounding and worsening existing threats, further disrupting our cities, rural areas, and natural communities. Great Lakes water levels have fluctuated dramatically in recent years, accelerating the spread of invasive species, flooding coastal communities, and disturbing the natural ebb and flow of wetland water levels.

Because marsh birds are sensitive to invasive species, and other water-related issues, Audubon and its partners can use them as a barometer for coastal wetland health across the Great Lakes.

Coastal wetlands are under threat by aggressive invasive species, such as the common reed, purple loosestrife, and narrowleaf cattail. These plants can overwhelm a wetland, creating dense stands of vegetation that reduce resources for foraging and nesting birds. Removing and controlling these invasives allows native species to compete.

Similarly, agricultural conversion, habitat fragmentation, and destructive woody invasive species threaten the critical grasslands of the Great Lakes, which are vitally important to rapidly declining species like Bobolink, Henslow’s Sparrow, and Eastern Meadowlark, and Short-eared Owl. Given that these birds need large-acreage grasslands to thrive, new invasive species threats are magnified and expensive to manage.

Invasive removal around the region

Audubon Great Lakes is working at Orland Grasslands and Bartel Grassland with partners at Forest Preserves of Cook County to establish and maintain critical habitat and remove invasive species like Callery Pear (Pyrus calleryana) which is a newer invasive species in the region that is spreading across the landscape like wildfire. These trees are extremely popular in new development projects due to their showy white flowers and their ability to grow quickly. However, these trees are not structurally sound and tend to die when limbs get broken off during storms with high winds. These large grassland complexes in northern Illinois harbor populations of rare grassland birds which rely on a needle-in-the-haystack method for nesting, where they place their nests directly on the ground. The larger the grassland, the less likely a predator will stumble on the nest. 

When trees like the Callery Pear are allowed to flourish and spread, they give predators a place to perch and pick off vulnerable grassland birds, like the Bobolink and the Henslow's Sparrow, two of the fastest declining grassland birds in the eastern United States. Audubon and partners are working to identify the best management practices for eliminating Callery Pear at key grassland sites across the region. 

Audubon Great Lakes is also working with partners in Michigan to remove invasive Common Reed (Phragmites australis) later this fall.  This invasive species management is part of the coordinated Black Tern Assessment project. Working with partners and volunteer surveyors, Audubon will be doing phragmites spot treatment at Portage Marsh, Wigwam Bay, and also recording observations of invasive species at Black Tern survey locations across the state. 

We are also working to enhance an 820-acre wetland by mechanically removing 25 acres of invasive hybridized cattail at St. Clair Flats State Wildlife Area in Michigan. Creating five, 5-acre openings at this Important Bird Area will help increase the amount of open water needed for waterfowl, the Black Tern, and outdoor recreationalists. 

In addition to invasive species removal, reintroducing native plants is an important part of restoration. Native plants are often displaced by invasive species, erosion, or earth moving. Planting native seedlings gives the wetlands a head start in the restoration process.

Signs of Success

With intensive restoration, we are already seeing sign of success and marsh bird populations have rebounded in the Great Lakes region, specifically at Calumet’s Big Marsh Park in southwest Chicago. In 2015, Audubon documented only two focal species. Following invasive species control and water management, those numbers increased to 11 species in 2018. State endangered and threatened species, such as the Least Bittern and the Common Gallinule, which had not been active at the site in over a decade, now regularly breed at Big Marsh Park. Similarly, populations of Henslow’s Sparrow are rebounding at sites like Orland Grassland due to intensive management undertaken by staff, volunteers, and interns.

You can help!

While we are working with partners, community members and volunteers around the Great Lakes region to remove invasives, they continue to grow.  There are some things you can do to help stop the spread of invasive species, such as choosing native plants when we landscape our yards, neighborhood parks, and public spaces. By planting native plants and removing non-native ornamentals, we can help restore vital habitat for birds in our communities while also helping to prevent invasive species from entering our natural areas.

In your backyard & community Audubon's Plants for Birds initiative offers many great practical tips for homeowners to create bird-friendly backyards and community gardens using native species. Properly selected native plants naturally require less time, energy, and water to maintain, and reduce the need for fertilizers and pesticides to be used.

Visit the Native Plants Database to learn more about what species are good to plant in your region, where you can find them, and for more tips for a bird-friendly backyard.