BRI’s Raptor Program Director, Chris DeSorbo climbs a tree to safely monitor a young eaglet in the nest.

The story of banded Bald Eagle Red X/R begins almost two decades ago, in early June 2006, near Shapleigh, Maine. There, BRI’s Raptor Program Director, Chris DeSorbo, found himself 60 feet up a white pine, face-to-face with the then six-week-old eaglet. At the time, Chris—in collaboration with Maine Inland Fisheries and Wildlife—was conducting a statewide assessment of mercury contamination by sampling what biologists call a “bioindicator species”, a species whose health reflects the condition of the broader ecosystem. In this case, the focus was on a predator at the top of the food chain: the Bald Eagle. Red X/R was one of 124 eaglets across the state to contribute to the study that year.

Each nestling is safely handled by experienced wildlife biologists; a small blood sample is taken for contaminant analysis, basic measurements are recorded to determine sex and age, and the bird is given a unique band ID—in this case, Silver 0629-52248 / Red X/R. The eaglets are then placed carefully back in their nests to continue their development. These unique ID numbers allow researchers to track an individual throughout its life. Every subsequent observation provides a crucial piece of the puzzle, offering a glimpse into where Maine’s Bald Eagles spend their time, for how long do they live, and what are common causes of mortality?

Red X/R was seen on Massabesic Lake in Auburn, NH in 2009 by Stuart Erhardt.

The second run-in with Red X/R was in November of the same year. By then the eaglet had fledged from its nest, still dawned in its dark brown hatch year plumage, and ventured out on its own, doing what young eagles do. It was spotted near the Back Cove walking path in Portland, just over a mile from BRI’s office. Many Portlandites spotted the young eagle feeding on a seal carcass washed up along the high tide line.

A few years later, Red X/R was spotted in New Hampshire, sitting high in pine trees along the waters edge. State lines don’t matter to these birds, but ecosystems rich in resources do—especially in the cold, winter months. This time the bird was in its Juvenile plumage, a lighter brown with mottled white mixed in. Bald Eagles don’t reach their full adult plumage with an iconic white head and tail and brown body until 4-5 years.

Red X/R was seen on Little Sebago Lake for the first time in 2012 by Bob Verrill.

In 2012, an ice fisherman first met Red X/R while ice-fishing on Little Sebago Lake. For some birds, winter signals the arrival of southbound migration, in search for warmer temps and greater food availability. Fortunately, Bald Eagles are remarkably adapted to withstand these cold conditions! They have a special circulation system in their feet where arteries and veins run close together, to minimize heat loss. Add in the fact that eagle feet are mostly made of hard tissues (bones and tendons rather than muscle) and you get a built-in cold-weather system that keeps heat loss to a minimum.

Red X/R seen in 2015 again on Little Sebago Lake in Maine by Robert Verrill.

Frozen lakes can actually be prime winter habitat for Bald Eagles, offering access to fish and carrion trapped by the ice. Little Sebago Lake proved to be one of those reliable places for Red X/R. He returned again and again, and in 2016, the same ice fisherman encountered the bird once more—this time feeding on white perch.

As the years go on, we got glimpses of Red X/R’s whereabouts through reported observations of banded birds—one of the best ways to engage in citizen science! These sightings help scientists track movements, habitat use, and survival over time. Red X/R was spotted more than 15 times, more than any other eagle banded by BRI. Though Red X/R has since passed, his legacy lives on in the data, and contributes to a clearer picture of Bald Eagle movement and habitat use.

To learn more about BRI’s ongoing efforts to understand movement patterns of Bald Eagles in Maine, read more here.

To learn more about Maine’s Bald Eagle population, please visit the Maine Department of Inland Fisheries and Wildlife website.