Each week last winter, Herb Wilson threw a sack of bird feed in the back of his Nissan and drove northwest 75 miles to Flagstaff Lake in Somerset County. The temperature at the lake, which sits at 1,400 feet elevation, seldom rose above 10 degrees. The only other human being in the area lived miles away. For Wilson, it was the perfect place for feeding birds. "I knew the higher up I went, the fewer people I'd run into. I was looking for a people-free environment," Wilson said. No people meant no competition for the eight bird-feeding stations that he set up over a 12-mile stretch. Wilson, a Colby College biology professor, wanted to see the effect feeding had on the lake's winter bird population, mainly chickadees and nut hatches. "I'd gotten very interested in the impact of bird feeders on birds, because there's been an explosion of backyard bird feeding," Wilson said. "It struck me that for many birds in the East, it's unlikely they'd go through their lives without experiencing a bird feeder." Wilson knew some birds, like the northern cardinal and the tufted titmouse, move north of their usual ranges if feeders are available. However, ornithologists have not done a great deal of work on the impact of feeding. By conducting his Flagstaff Lake project, Wilson hoped to learn more about how often birds visited feeders and how the feeders affected birds' survival rates during winter. He began by setting out a mist net, which is made of fine mesh and is nearly invisible to birds. Wilson placed color bands on 110 chickadees and 20 redbreasted nuthatches that he trapped around various feeding stations. The bands let him differentiate between individuals, as well as make projections about the total number of birds using the feeders. "What I found blew me away. In any given day, according to my analysis, I had more than 100 chickadees coming to each feeder," he said. Normally, chickadees flock in groups of six to 10 and keep other chickadees out of their territories, which range from 15 to 30 acres in size. But with abundant food available, Wilson said, "It wasn't worth their time for the resident flock to defend their territory." Various flocks would visit the feeders before returning to their own territories. The color bands allowed Wilson to see that chickadees exhibit some individuality when it comes to frequenting feeders. Some birds, he found, visit five or six times more often than others. Wilson has no explanation. "I don't know if birds that come to feeders a lot are not particularly good at finding other food or if they are the dominant birds, keeping others away," Wilson said. Wilson has long been interested in birds. His mother claims that his first word was "bird." But it was not until after earning his doctorate in biology that his formal study of birds began. During the 1980s, he studied mud flat ecology in Nova Scotia. Gradually, he began concentrating on the role of migratory sandpipers. Today, he specializes in the foraging behavior of birds. While at Flagstaff Lake, Wilson hoped to resolve questions about how feeders affect the winter survival rates of chickadees. "It looked like survivorship was extended, but the data [from previous studies] were inconclusive." Under typical conditions, roughly 65 percent of Wilson's birds would have been expected to survive the winter. However, the rate for birds at his feeding stations, Wilson said, "was over 90 percent for the five-month period. That's pretty darn high for the harshness of the environment." Nonetheless, the increased winter survival isn't likely to lead to longer life spans. Wilson expected predators to keep the population down. During his visits to the lake, Wilson endured temperatures as low as minus 20 - something that he had hoped for. The low temperatures allowed him to study how the cold affected feeder use. Laboratory research had shown that below 15 degrees, chickadees shiver. Wilson predicted that as the temperature dropped birds would increase their trips to the feeders, in order to replenish the energy lost to shivering. But to his surprise, Wilson saw no increase. He concluded that while chickadees still needed extra energy, they weren't counting on feeders to provide it. Wilson's Flagstaff Lake research is useful for backyard bird enthusiasts. According to Wilson, it's not necessary to worry about feeders that run out. "What chickadees are clearly not doing is counting on one source of food. When somebody stops feeding, the birds move on," Wilson said. Wilson also cautions against mistaking the five or six chickadees seen at a feeder for the same ones that were there earlier in the day. "You're entertaining up to 40 birds a week," he said. Wilson offered backyard birders information he knew prior to his Flagstaff Lake trips - stock the feeder with black oil sunflower seeds. "If you have black seeds and your neighbor does not," Wilson said, "you're going to have chickadees and your neighbor is not."