Raptors, or birds of prey, are tricky to identify. The task is even more difficult if the objects are flying in a flock, like migration raptors usually do. The knowledge of flying technique, physical characteristics and flying location are puzzle pieces that need to be assembled to form a solid “picture” in order to find the species.
To identify these predators, the very first thing to do is to observe the body proportions, wing span and wing shape and focus on their physical appearance. Wing tips could be sharp, rounded or finger-like. Also observe the tail length and tip shape as it could be squared, rounded or forked.
The pattern in the underwings is also a key trait while the bird in flight, in particular primary wing feathers. Check for the presence of plumage pattern and line feature in the wings. Tail shape is important to facilitate the identification process.
To identify a raptor specifically requires a length of time. The easiest way is by looking at their size, flight technique, and silhouette.
Eagle (elang)
This bird of prey has a large body size with a wide wingspan and a fan-shaped tail. Eagles usually fly with their wings spread out after a few flaps.
Buteo
It has wide and rounded wings. The body is a bit fat with a fan-like tail. Buteos are able to fly without flapping their wings too much, commonly encountered when riding thermals.
Accipiter (elang-alap)
This forest-inhabiting species has short rounded wings and a long tail. It flies by quickly flapping its wings then glides.
Falcon (alap-alap)
It has long pointed wings, a relatively big head, a long tail, and is small in size compared to other raptors. Falcons fly with rapid wing flaps and are known for performing a fast swoop down-manoeuvre technique when catching prey.
Field notes
Notes on raptor description would be very useful before conducting identification. The easier way to identify is when they are flying, but it is difficult due to their very short flight period—usually lasting only one to two minutes. Migrating raptors even can only be seen for a few seconds on their flyway spots.
Taking notes as much and as soon as possible is crucial, due to the raptor variation on individual and age levels. It is often more difficult to identify juveniles than adults. Many times, we can only get a glance of raptor in flight and not close enough to identify. If you have a camera with a long lens, try taking photos in several series and at various angles. Have fun watching raptors!
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Indonesia is one of the transit areas and destinations for various migratory birds from all over the world. Indonesia is the main migratory destination for eagles. This bird of prey flies through a route known as the East Asia Continental Flyway, which stretches from Siberia to Southeast Asia.
Estimated about one million raptors will traverse the Eastern Mainland Corridor which covers around seven thousand kilometres in length. One observing spot for raptor migration is Paragliding Hill in Puncak, Bogor, West Java.
We invite you to participate in migrating raptor observation on Saturday, October 28 2017 at 07.00 WIB at Paragliding Hill, Puncak, Bogor. Bring along your family or relatives to welcome these travellers from the north. Further information: (WA/LINE) 0811-11454-88