The Sounds of Wing Haven

Acoustic monitoring reveals extraordinary bird diversity in Indiana’s premier nature preserve

Six Months of Listening to Nature

ACRES is now eight years into a 200-year ecological reflection project at Wing Haven in Steuben County, Indiana. During this time, we conducted floristic inventories, surveyed small mammals, and sampled the lake and adjacent wetlands for eDNA analysis. All this information allows us to build a baseline to compare against future research.

The Long-Term Vision

Because 200 years is a long time, and there are only so many things to sample within a 160-acre property, our study design focuses on resampling many of the same taxa (a scientifically classified group) at recurring intervals. Resampling will allow us to identify trends and predict species presence and population sizes. This information may also help guide management decisions.

Passive Acoustic Monitoring

To date, we have obtained a lot of helpful information about species inhabiting the preserve year-round. However, we have little information on migratory species that use the preserve for breeding or as a stopover location to rest and feed before heading further north or south.

How We Captured the Sounds of Wing Haven

To fill this knowledge gap, ACRES purchased two passive wildlife recording devices. These two devices listened from April 2024 until November 2024, capturing the sounds of Wing Haven throughout multiple seasons. Together, they allowed us to collect considerable data over six months, with relatively little staff time spent on the project.

Once the 2 terabytes of data were processed, we had a species list containing:

• 4 to 6 species of bats
• 150-167 species of birds
• 11 species of insects
• 6 species of frogs
• Plus an occasional firework!

The Birds of Wing Haven

Endangered and Rare Species at Wing Haven

Ten species of endangered birds have been identified in Wing Haven, along with an additional 13 species of special concern (as designated by the Indiana DNR). While some recorded species are new county occurrences, others have not been reported in several decades.

Marsh Birds

The recording devices detected several species of wading and marsh birds, often very difficult to locate visually but clearly present in the acoustic data from Wing Haven. Most notable were:

• King Rail (State endangered)
• Virginia Rail
• Common Gallinule (Rare in northern Indiana)
• Black Tern
• American Bittern (State endangered)
• Least Bittern (Smallest heron species)
• Marsh Wren
• Sedge Wren

Warbler Diversity

Wing Haven’s adjacent uplands also contained some pretty neat species, including the following warblers:

• Golden-winged Warbler (State endangered)
• Hooded Warbler
• Black-and-white Warbler
• Worm-eating Warbler

Ongoing Analysis

It did not go unnoticed that a range of species was detected for both bats and birds. That range indicated additional analysis is needed before we can confirm the presence of several species. There are likely two state-endangered species of bats using the site and possibly two to three additional endangered birds.

Please stay tuned for an update; we will soon have local experts listening closely to these isolated recordings.

The Importance of Large, Protected Habitats

Wing Haven is one of ACRES most biologically diverse properties. The high level of biodiversity can be attributed to the mosaic of plant communities and the overall quality and amount of available habitat within and surrounding the preserve. Large, contiguous, high-qualifying natural areas are crucial for the survival of many species that inhabit them. Through careful planning and partnerships made long ago, this priority area and others like it will remain protected and serve as valuable breeding and resting habitats for 100 or more species of migrating birds for generations to come.

ACRES plans to utilize the recording devices within the site again in 2029 and, in the meantime, will be deploying them within other priority areas across the service area.

Experience Wing Haven for Yourself

Wing Haven is one of our 32 nature preserves that has a trail system open to the public from dawn to dusk. Experience firsthand the remarkable biodiversity captured in our acoustic research.