Doug Wood has been volunteering at the Hawk Mountain Sanctuary since visiting it during its 1984 golden jubilee.

On a recent Saturday morning, the New Ringold, Penn., resident got up at 5:00 a.m., in order to be at the trail head to the mountain's North Lookout by six. Twenty minutes later he was at his post as the counter of record for the day. The sun wouldn't rise for another 20 minutes.

Sunrise at Hawk Mountain. ©GreenWorks photo by Dan Simon

"It was dark, but it was first light, and my eyes got adjusted to it," Wood recalled. "So I didn't need a flashlight."

Wood, who's one of a number of volunteers who donate their free time keeping track of the raptor migration, has a set procedure to count the birds. The procedure's a bit more detailed than just spotting a bird and making a tick mark on a sheet of paper.

"We basically have a plane in the sky as the birds approach us they're coming from the north east and passing by us and continuing on their migration," he said. "What we're doing is identifying species if we can, identifying adult and immature birds within the species, and also we're taking measurements for wind direction, the flight of the birds, how high they're flying, etc."

Doug Woods tests wind direction at Hawk Mountain's North Lookout point. ©GreenWorks photo by Dan Simon

While Wood's method of determining wind direction looks suspiciously like a man blowing soap bubbles, other elements of the count are a bit more challenging. The birds adopt a more leisurely pace than the average commuter as they take advantage of rising thermal air currents to gain altitude without having to work too hard. This means a bird may be circling their way up the same air current over and over as they get higher in the sky. The counters have to be sure the bird is actually continuing its journey and not just hanging out on a thermal.

"I just love the birds," Wood said. "I really enjoy seeing the migration. This morning we're here for the warblers, but I love seeing the migration of the hawks and helping educate people as to why what we're doing here is important.

"This helps monitor the health of the birds. It's one of the ways of seeing how a certain species of bird is increasing or decreasing. They're a barometer for the whole ecology."