Eagle Month in The Last Green Valley: The Midwinter Eagle Survey
Every January for the past 11 years I’ve visited the Quinebaug Valley Trout Hatchery to look for eagles. Last Saturday I returned again, this time with seven other eagle searchers. We were there to take part in the annual Midwinter Eagle Survey organized by the Connecticut Department of Energy & Environmental Protection (CT DEEP) and the US Army Corps of Engineers.
The hatchery, located in the Central Village area of Plainfield, encompasses about 2,000 acres with about one mile of frontage along the Quinebaug River. The wide open field below the hatcheries’ trout tanks has 360-degree views of the sky for thousands of feet. If you’re looking for eagles, it’s helpful to have many eyes on the sky and scanning along the bordering tree line. It would be easy to miss an eagle flying over but with a half dozen or more folks we can effectively cover the large area.
Since 2010 I have assisted CT DEEP in organizing midwinter eagle survey teams within the 26 Connecticut towns of The Last Green Valley National Heritage Corridor. It started following the 2009 TLGV program Source to Sea: Connecting the Drops in The Last Green Valley. During Source to Sea we paddled the main stem rivers and a few tributaries of the Thames watershed all the way to Long Island Sound. Our intent was to draw attention to the water resources of the National Heritage Corridor, and along the way we encountered many bald eagles.
That fall I read a report in CT Wildlife Magazine showing one bald eagle on the Quinebaug River. Well, we knew there were many more than that, so I contacted Jenny Dickson of CT DEEP, who at the time was coordinating the midwinter survey, to see if she could use more volunteers for the Quinebaug River.
She was glad for the help and in December sent me the information on the survey with specific protocols and data sheets. I asked people who had paddled on our Source to Sea adventures and on Jan. 9, 2010 we had 13 volunteers in five teams surveying ten locations on the Quinebaug River from West Thompson to Jewett City.
That first year our 13 volunteers counted 11 bald eagles at six of the locations. This year we placed 46 volunteers at 23 locations along the Quinebaug, Shetucket, Willimantic and Natchaug rivers as well as at 14 lakes and ponds. Many of our teams visit more than one location. Last Saturday, between 7 – 11 a.m., we counted 35 bald eagles.
The key to success is the 18 team leaders who each year view the same locations and take responsibility for accurately recording their findings. Some of the team leaders have been doing this since our first year. Each has years of experience identifying eagles and takes charge of filling out the important data sheets for CT DEEP. Their experience ensures confidence for the wildlife biologists that the data is correct and the survey followed established protocols.
This year my experience was much like it has been since my first survey in 2010. I always arrive at the hatchery by 6:45 a.m. to meet up with my team volunteers. We want to be situated at our survey location right at 7 a.m. We take binoculars and walk into the large open field and scan the sky and bordering tree line for eagles. The eagles frequently roost for the evening within conifers, especially pines and hemlocks, which help buffer the cold wind. As the sun rises and the air warms, they will start to move and begin hunting for food.
We make our way along the dirt road that circumnavigates the large open field, scanning the sky as we go we and stopping whenever we see a large bird flying to get a good look with binoculars. It might be a great blue heron or perhaps a crow and sometimes a hawk, osprey or soaring turkey vulture. However, the brilliant white head and tail of the bald eagle and a wingspan of six feet really stands out. Adult bald eagles are easy to identify, but it can be a bit trickier identifying the juvenile eagles.
Eagles can live up to 30 years in the wild. When they fledge, juvenile eagles are the same size as adults, but it takes about five years for them to get the white head and tail. Juvenile eagles are mostly brown with white speckling on their bodies and wings. Sometimes young eagles can be mistaken for turkey vulture, hawk or osprey. Eagles are bigger than hawks and ospreys and have a different way of soaring and shape to the wings than turkey vultures. With experience they are easy to distinguish.
We make our way to about the halfway point of the open field where an electric transmission line with tall metal towers crosses the Quinebaug River and continues over the field southward over the Moosup River and into Plainfield. These tall poles are favorite locations for roosting eagles, hawks and osprey and sometimes are used by ospreys for building nests.
Eagles typically roost and build their nests in the tallest trees on or near water and are attracted to tall electric transmission towers with a 360-degree view. For the past several years our team has enjoyed watching a pair of bald eagles roosting together on the towers. They arrived again this year just before 8 am and our team was able to get several pictures of them both together. My guess is they are the adult pair that has a nest about four miles from the hatchery.
During the survey we use basic maps of the survey location and write on them the time, location and flight direction of any eagles we see. Some of our survey locations along rivers are only a few miles apart so recording the time and flight direction is important. This information helps the CT DEEP biologist determine if a bird has been counted more than once during the four-hour survey time. It is also important to note that the eagles we are seeing are predominately bald eagles. I did record a juvenile golden eagle at the hatchery three years ago, however, they are not common in New England. At 11 a.m. the survey time is over, so we head back to our vehicles to complete the data sheet. Most years all the survey teams meet up for lunch to compare notes and take a group picture. The pandemic kept the teams from gathering this year, but I spoke with all on the phone that day to get their numbers and information.
You may be wondering why we are doing this survey during the winter months instead of warmer times of the year. Eagles migrate south in the winter to take advantage of our warmer weather and open water. This concentration of eagles makes it easier to count and establish a more accurate estimation of the eagle population statewide. The midwinter survey is also conducted on the same day in many states throughout the country, providing a quick and easy snapshot of the national population of these amazing birds. Unfortunately, we don’t have comparable data for the Massachusetts towns in our National Heritage Corridor as Massachusetts wildlife agencies monitor bald eagle nests in the spring instead.
There is nothing quite like seeing a soaring bald eagle and reveling in their beauty and majesty. I never tire of witnessing them and consider myself so fortunate to be part of this important work. After 11 years of helping with the midwinter survey I am still enthralled by these amazing birds – our national symbol.
We live in a beautiful place called The Last Green Valley. I hope you’ll join me as we enjoy it, care for it, and pass it on.
Bill Reid is the Chief Ranger of The Last Green Valley National Heritage Corridor. He has lived in and explored the region for 40 years and can be reached at firstname.lastname@example.org
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