Turkey Vulture Program yields data
Local effort could help protect bird of prey that has an important role in North America’s ecosystem
Published: December 8, 2013
TOWANDA — On May 15, a research biologist and his assistant caught two adult turkey vultures on the grounds of Towanda High School, and then affixed a lightweight transmitter to each of their backs so that members of the public and researchers could monitor where they travel to.
The device transmits the GPS coordinates of these scavenging birds of prey every three hours to a satellite.
Because the bird’s location is then uploaded to the Internet, there are maps on the Internet that the public can look at in order to see where the bird has traveled to.
After May 15, one of birds, named “Tesla” by Towanda School District students, spent time in New York state and southern Pennsylvania before returning to Towanda, according to the biologist, David Barber of Hawk Mountain Sanctuary.
The other bird, named Black Knight, traveled much less extensively than Tesla, moving mostly around northeastern Pennsylvania, Barber said in an email to The Daily Review.
One of the questions that researchers wanted to answer was where turkey vultures from the Towanda area spend the winter, Barber said.
“At least for these two birds, we have our answer: Florida,” Barber wrote.
Black Knight and Tesla, which have wingspans between five and six feet, are currently in the Sunshine State, he said.
Black Knight is currently closer to Miami, while Tesla is currently closer to Orlando and Disney World, Keith Bildstein, Hawk Mountain Sanctuary’s director of conservation services, said on Tuesday.
Catching the two birds and affixing transmitters to them is part of a joint project between Hawk Mountain Sanctuary and the Towanda School District to monitor the movements of turkey vultures and study how the birds interact with their environment, Bildstein has said.
The turkey vulture project at Towanda High is in turn part of a larger project being carried out by Hawk Mountain Sanctuary to monitor the movements of turkey vultures, which has involved the placement of devices that transmit GPS coordinates — called satellite telemetry units — on the backs of over 40 turkey vultures in the eastern United States, California, Arizona, Argentina and Saskatchewan, Canada, Bildstein said.
While turkey vultures are common, scientists at Hawk Mountain Sanctuary hope to learn more about the birds in order to avoid catastrophic population declines, which have occurred in other types of vultures in many parts of Africa and southern Asia, according to Hawk Mountain Sanctuary’s website.
Turkey vultures play an important role in the ecology in North America, Bildstein said.
“They are nature’s sanitation engineers,” Bildstein said. “They go around and scavenge animals (feed on animal carcasses).”
And there is a lot of evidence that suggests that the turkey vultures’ feeding on carcasses helps prevent the spread of disease, he said.
Besides determining where the area’s turkey vultures migrate to in the winter, scientists at Hawk Mountain Sanctuary will use data transmitted by the birds to answer a number of other questions, such as how far they range in a day, and whether they use the same roost or move around from roost to roost, Barber said.
While turkey vultures all belong to the same species, there is a variation in where they migrate to.
For example, Hawk Mountain Sanctuary found that of the dozen turkey vultures that if has affixed satellite telemetry units to in and around Pennsylvania, approximately half migrated as far as Florida, while the rest migrated hardly at all, only traveling as far as southern Pennsylvania or southern New Jersey, Bildstein said.
Hawk Mountain Sanctuary is currently trying to raise funds to purchase additional satellite telemetry units, which would be placed on at least four more turkey vultures that would be caught in Bradford County, he said.
“Our goal is to move forward with the program and put four additional units on turkey vultures this coming year” in Bradford County, he said. “We will try to catch them at the high school (on the Towanda High School grounds).”
Hawk Mountain researchers find that working with six to eight turkey vultures from a particular geographical area gives them a much better picture of the variability in the population of the birds in that area, including variations in where they travel to, Bildstein explained.
“Two is really a minimal number.”
Towanda High School’s roof is a place where turkey vultures are often seen, Barber has said. The birds spend the night in a roost behind the school and then in the morning fly to the roof to warm up and wait for columns of hot air to start rising from the pavement next to the building, which they use to gain altitude when they take flight and disperse, Barber has said.
While Tesla’s transmitter has worked flawlessly, transmitting 1,327 GPS locations since May 15, Black Knight’s transmitter has worked sporadically, collecting only 276 GPS locations, Barber wrote in his Nov. 13 email.
It is not unusual for these satellite telemetry units, which are powered by solar-powered batteries, to stop working at times, Bildstein said.
“There are many reasons why that could occur,” he said. “Sometimes there is a malfunction in the unit. Sometimes feathering on the bird covers part of the (sunlight receptor area) that powers the unit. It could be that Black Knight, for one reason or another, is hanging out in a lot of (areas which the sun is blocked out, such as in the shade of trees).”
Hawk Mountain Sanctuary is “on the cutting edge” of using satellite telemetry units to monitor birds’ movements, so kinks in their operation are still being worked out, he said.
The Towanda School District has purchased two video cameras, which it plans to place on Towanda High’s roof in order to monitor the turkey vultures’ behavior, Dayna Dawsey, chair of the school’s science department, said.
The school district’s goal is to establish a website where students and other members of the public can “watch” the birds in real time through the eyes of the cameras, she explained..
However, the school district could not deploy the cameras right away, because it had to wait for a project to be completed that replaced most of the school’s roof, she said.
The school district plans to install the cameras soon after turkey vultures return to the school this spring, she said.
The video cameras were purchased using a donation from the Towanda Area School District Education Foundation, she said.
James Loewenstein can be reached at (570) 265-1633; or email: firstname.lastname@example.org