Where the Birds Are

The consequences of even one bird smashing into a plane's windshield or being pulled into an engine can be disastrous

• NWF Staff
• Feb 01, 2000

Although collisions with birds in flight are infrequent causes of airplane accidents, the consequences of even one bird smashing into a plane's windshield or being pulled into an engine can be disastrous. That's why several scientists from various institutions recently joined forces with researchers at the Center for Conservation Research and Technology at the University of Maryland to figure out how to alert pilots about where the birds are. The researchers first fitted ten American white pelicans in Nevada with satellite transmitters. Then they tracked the birds' flights and compared the results with the weather and atmospheric conditions. Pelicans are soaring birds, and like glider pilots, they seek out "lift," usually in the form of thermals rising from the ground.

The study found that in the morning or when clouds kept the ground cool, birds on their way to and from their breeding colony and foraging grounds tended to fly at relatively low levels, as low as 100 feet above the ground. When thermals rose from the warmed earth later in the day, flying pelicans rose with the lift, as high as 10,000 feet. Their maximum limit apparently is 14,000 feet, which the birds can reach in a mere 10 minutes.

The team is optimistic that it can predict a day in advance how high various birds are likely to soar--and that pilots then can make sure to aim their planes higher than the birds, taking the information into account much as they do a weather forecast. The other species being investigated in the ongoing study include Swainson's hawks, turkey vultures, black vultures and red-tailed hawks.