From RRP's FB page on 9/12/16
Raptor Resource Project shared Neil Rettig Productions's post.
An extremely cool share from Neil Rettig Productions. Note how the Philippine Eagle soars fairly flat, with just the tips of its wings curled up and its wing slots spread wide. The wide wing slots reduce the difference in pressure between the top and bottom of the wing to alleviate drag.
The Philippine Eagle's tail remains in a narrow line behind until it begins to flap, at which point it appears to tilt just a little bit, especially on the first two strokes. It takes a lot of lift to keep a bird this big up in the air!
Knowing a bird's shape and flight behavior can be very helpful in identifying it at a distance. A peregrine falcon's dynamic flying sickle, a turkey vulture's tilty-winged 'V', an osprey's 'M', and the flat lines of a soaring eagle are quite distinctive from one another and can be useful in preliminary ID.
Neil Rettig Productions - September 9 at 7:59pm
This footage Neil shot on our expedition in the Philippines is being used to illustrate wingbeat trajectory and shape in a new edition of the Handbook of Bird Biology published by Cornell. The media team at Cornell Lab of Ornithology is working hard editing the documentary on the Philippine Eagle that will show much more of these amazing birds, their plight, and the people working hard to save them and their habitat.
Slow Motion Philippine Eagle Flight -
https://www.youtube.com/watch?v=NiIgrPNFFxkPublished on Jul 13, 2016
"To understand the unique flight styles of different bird species, scientists use a technique called wing tracing. It involves tracing the trajectory of a point on their wing during a series of wingbeats. The pattern of a bird's wingbeat depends on how far a bird can move its wing in any given direction, which is determined by the length and shape of the wing. Soaring birds such as this Philippine Eagle, for example, show an elliptical shaped wingtip path when viewed from the side.
This video accompanies Chapter 5, Avian Flight, Handbook of Bird Biology 3rd Edition from the Cornell Lab of Ornithology and Wiley Publishing."
http://birdbiology.org