Connecticut Bats: More Misunderstood than Spooky

Each year, the approach of Halloween creates a spike in peoples’ interest in bats. These fascinating creatures serve several important roles in maintaining healthy ecological balance, but they are often misunderstood.

Connecticut is home to nine different bat species which are generally divided into two groups. Those that are cave-dwelling, including big and little brown bats, tricolored bats, and northern long-eared bats, tend to live in social groups.

These species search out any underground caverns that offer stable temperatures during the winter to hibernate. The other group are known as tree-roosting bats, and they include eastern red, silver-haired, and hoary bats. These species tend to be more solitary, and while they still hibernate, they often migrate longer distances to warmer areas to do so.

Many of our native bat species are natural predators of large numbers of insects including mosquitoes, beetles, leafhoppers, and moths, some of which are agricultural pests, and others that can spread disease.

Like other wild animals in our region, many bat populations are struggling due to the impacts of habitat fragmentation caused by human development. Additionally, white-nosed syndrome, a fungal disease introduced to New York in 2006, has spread to neighboring states including Connecticut.

White-nosed syndrome was brought from Europe and has caused dramatic declines in both big and little brown bats, tricolored bats, and northern-long eared bats. White-nosed syndrome kills bats by disrupting their hibernation periods causing them to burn extra fat reserves, often leading to poor health or starvation.

Some recent evidence has suggested that some affected species are beginning to rebound, but overall population declines have been severe over the past decade.

State biologists are monitoring bat populations in many areas of Connecticut, including Greenwich. Over the past several years monitoring has been conducted around Greenwich Land Trust’s Converse Brook Preserve.

Five of the nine bat species native to Connecticut were found to be utilizing the property, some for hibernation, and others just for foraging. These monitoring efforts provide important data about what habitats bats are using most. Surveys also provide some indications about population health for different species.

If you’d like to learn more about our local bats here in Connecticut, and specifically around Greenwich, state biologist Dr. Devaughn Fraser will be giving a talk at Greenwich Land Trust from 6:00 to 7:30 p.m. next Wednesday, October 25.

Dr. Fraser will talk about the diversity of bats we have here in Connecticut, their unique evolutionary history, and how we can monitor and protect these critical members of our natural communities. To register, visit Greenwich Land Trust.

Dan Brubaker
Director of Conservation and Outreach
Greenwich Land Trust