Chances are, if you’ve been atop Bradbury Mountain in Pownal over the past month, you might have seen wildlife biologist Andrew Sharp peering out at the view through his high-powered spotting scope.
“We’ve had two big days so far,” Sharp said. “Our biggest day was 858.”
Sharp is not referring to tourists, but rather another great seasonal migration in Maine: hawks.
According to Sharp, who is the official hawk-watcher for the 2021 season, most raptors this far north migrate south for the winter. While some of them just go as far as Virginia or New York, other species, such as broad-wing hawks, go all the way down into South America.
On average, more than 1,700 Broad-winged Hawks, 400 Osprey and 75 Bald Eagles soar by Bradbury Mountain each season.
“This time of year, as spring is arriving, they’re all coming back,” Sharp said. “We can see this stream of raptors heading north and what we do is we identify everything we see, and we tally up everything we see and then that data goes into an international database.”
The lookout from the summit of Bradbury is an ideal location to collect this data, as raptors like to follow geographic features like mountains and coastlines as they migrate, Sharp added, also noting that the largest day last year saw around 1,800 birds.
The study at Bradbury has recorded 19 types of raptors — also known as birds of prey — which include hawks, eagles, vultures and other birds. The number that are documented per day is highly dependent on wind direction and speed.
While some birds might stop a mile past Bradbury, others go as far north as Hudson Bay.
Sharp’s efforts are part of a larger 14-year data collection project that occurs annually at Bradbury Mountain and focuses on monitoring population trends and distribution changes of different raptors.
The results are then studied alongside other data produced from various monitoring sites across North America in what is known as the Raptor Population Index. This, in turn, offers greater insight into overall raptor population trends.
The project runs at Bradbury from March 15 to May 15. Although weather dependent, Sharp said he typically monitors six days-a-week and is currently on day 42 of 62.
“So, our data is important, but also the outreach and education potential of having someone stand up here all day every day for two months goes beyond just the simple collection of data,” said Freeport Wild Bird Supply co-owner Derek Lovitch.
Freeport Wild Bird Supply has sponsored the Bradbury hawk-watch since it began in 2007.
“Birders get to come and have an expert point out birds and teach them how to identify them, also it’s just fun,” Lovitch added, highlighting the social aspect of the hobby.
Sharp said that on a sunny Saturday even in the spring, hundreds of people will stop by the summit.
“I don’t think I could separate myself from birding, it’s just who I am,” Lovitch said.
Both Lovitch and Sharp said that increased counts over the years at various hawk watch locations suggest some populations of raptors are increasing.
“Overall birds in North America are declining, we’ve lost 3 billion birds in the last 50 years,” Sharp said, citing habitat loss, free ranging cats, other predators and window strikes. “Raptors are one of the few cohorts that’s actually doing really good and mostly that’s because of the banning of DDT.”
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