Thursday, August 4, 2011

Peregrine Falcon Banding


On June 9, 2011, several of our interns and I had the rare opportunity to participate in our first Peregrine Falcon banding with World Bird Sanctuary.  We banded the babies from a nest box at the AT&T building in downtown St. Louis. 
 The AT&T building nestbox with a curious Peregrine Falcon chick peeking out at us.
The World Bird Sanctuary has been working to increase the number of wild Peregrine Falcons in the St. Louis area since 1985.  We began by releasing or hacking young captive bred Peregrine Falcons to help increase the number of Peregrines in the wild in the U.S.  At that point in time the Peregrine Falcon was listed as an endangered Species in the U.S., mostly due to the pesticide DDT.

 In 1991 WBS celebrated the hatching of the first wild Peregrine Falcon in over 100 years in Missouri.  WBS no longer releases Peregrines in the St. Louis area because there are several breeding pairs in the area.  World Bird Sanctuary and many other dedicated organizations around the country have helped to bring the Peregrine Falcon back from the brink of extinction. Peregrine Falcons are now nesting in both nest boxes and cliffs in the St. Louis area, on both sides of the river. 

The location I recently had the opportunity to visit was the nest at the AT&T building in Downtown St. Louis.  The Peregrine Falcon has made a remarkable comeback, and at this point the number of nesting Peregrines in the U.S. may exceed pre-DDT numbers.
 We found five young Peregrine Falcons
We traveled up to the 43rd floor when we arrived at One Bird Center.  We went out onto the balcony with the nest box and found 5 young Falcons. After determining that the parents were nowhere to be seen we removed the chicks from the box to be banded.
 We quickly banded the chick and took blood samples
Working quickly before the parents returned, we brought the baby Peregrines inside the building where we banded the babies and took some blood. We take blood as part of a research program that will look at the Peregrines nesting in cities to determine if they are building up any toxins in their bodies that might have a negative effect on the population.  We also place two colored bands on the young that will assist biologists in identifying the bird.  The numbers of the bands are sent to the U.S. Geological Service, which has the banding lab that keeps track of all the bands.  If the birds are ever trapped, found injured, or found dead the numbers are reported to the lab and they can tell when the bird was banded, its age and if it was ever seen before.  Banding is a great way for biologists to study bird movements and assists with helping to determine the overall population of a species.  The AT&T box had three males and two females.
 The parents circled anxiously as we returned the babies to the nestbox
Once we finished banding the birds we looked them over again and then placed them back in their nest box.  Mom and Dad were ready to greet us.  As a few of the babies made noise while being placed back in the box Mom and Dad flew overhead making sure that we knew that our presence was not welcome.  The female flew very close, giving us an excellent view of an angry mother Falcon in flight, while the male circled above our heads calling. At this close perspective you could really see the size difference between the male and female.  In birds of prey the female is usually about a third larger than the male. 
 An angry mother Falcon keeping a close eye on us
While putting the babies back in the box we also examined the feathers that were in the box, which belonged to the prey the adults were bringing to the nest for the babies.  The birds on the AT&T building had a lot of pigeon and dove feathers. 

This was an amazing experience—one that the interns and I will never forget.

Submitted by Cathy Spahn, World Bird Sanctuary Field Studies Coordinator

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