How Habitat Restoration in the Montezuma Wetlands Complex is Saving Endangered Black Terns

Article written by Montezuma Audubon Center intern Olivia Mathews.

Working alongside a volunteer, I haul a canoe into the slow-moving, shallow water at Knox Marsellus Marsh within the Montezuma National Wildlife Refuge. The canoe slides against the soft sapric peat that forms the surface floor of the marsh, a popular breeding ground for our target species: water chestnut. 

It doesn’t take long to spot the floating aquatic plant that emerges in bundles of diamond-shaped rosettes clustered in close proximity to each other. Around 20 other volunteers, U.S. Fish and Wildlife Services staff, and Montezuma Audubon Center staff spread out and surround the patches. 

I lower my arms beneath the surface, methodically pulling the long, cord-like stem and attached barbed nutlet into the bulging mesh bags. A Black Tern swoops low next to us, its wings gracefully dipping just above the surface. 

To me, it represents what this community works tirelessly every week for: the restoration of species and habitat.

Since starting my internship with the Montezuma Audubon Center, I have witnessed the importance of conservation action through community engagement, and the impact it has made across the Montezuma Wetlands Complex. One of the chief projects we worked on was through restoring habitat for and monitoring certain target species, such as the Black Tern. Removing water chestnut was a big part of this work.

Water chestnut, an extremely invasive aquatic species, has become a high management priority in the last six years around the Montezuma Wetlands Complex. Its ability to produce multiple shoots from one nutlet allows it to cover a wide expanse and choke out other critical vegetation and nesting spaces for bird species—including Black Terns.

We saw a substantial decrease in water chestnut through our efforts to prevent further spreading since starting the Montezuma Alliance for the Restoration of Species and Habitats (MARSH!)—our volunteer program. Due to the combined effort of volunteers and staff, we were able to remove a large percentage of the growth from our focus sites this summer, totaling 7,690 pounds of water chestnut!

During my internship, I saw the tangible impact of this habitat remediation and management firsthand. I had the privilege of being part of the New York State Department of Environmental Conservation’s annual Black Tern Colony Survey this summer.

Black Terns are an endangered species in New York due primarily to habitat loss of their wetland home. These annual surveys allow us to keep tabs on their population and better understand their habitat needs.

During the survey, 24 Montezuma Wetlands Complex staff and volunteers were stationed in pairs across 8 marsh units on the Montezuma Wildlife Refuge and Northern Montezuma Wildlife Management Area. While paddling through our unit, we counted the maximum number of birds seen at any one point in time during the survey to avoid double-counting birds and overestimating population sizes. For those birds, we recorded their age class, behavior, and whether nests or eggs were observed, and observation times.

At our site we found several adult Black Terns and, most thrillingly, a juvenile, identifiable by its mottled dark feathers creeping up its head and body.

The results of this survey yielded 132 individuals counted across the Montezuma Wetland Complex— the highest recorded number of Black Terns since the inception of these surveys in 1982, as well as the highest number of Black Terns on the Montezuma Wetlands Complex reported since 1966! 

This signifies that the efforts by our partners, staff, and volunteers in habitat restoration and management are essential and have a tangible positive impact. Black Terns are an indicator species for the health of freshwater wetland habitats and their population growth and nesting success indicates a healthy emergent wetland and stable water levels.

We so often hear about the negative impact humans have on their environment.  Indeed, the spread of invasive species and habitat degradation have largely been human caused, but I have been encouraged over the past 10 weeks by the dedication given to managing these wetlands and the tangible impact these consistent conservation efforts can have. 

We carry this responsibility together, and I am grateful to be a part of the continuous restoration of the Montezuma Wetlands Complex and be a witness to the incredible community that forms from people of all ages, occupations, and backgrounds, working to protect this ecosystem that provides for the birds and provides for us.