Black Falcon
Falco subniger
The information in this section is based on recent descriptions by several authors (notably, Debus & Davies 2012, Debus & Olsen 2011, Morcombe 2002 and Birds in Backyards n.d.). Size (adult, beak to tail): 45 – 56 cm (average 50 cm), tail makes up about half the length. Note: Females are larger than males - this is a form of sexual dimorphism. Average weight: 833 g (female) 582 g (male). Wing span: 95 –115 cm. Voice: The most common call is similar to the 'cackle' of the peregrine falcon but is slower and deeper – gaak-gaar-gaak. The guttural call is shorter and more rapid when being attacked or when intruders are nearby – gak-gak-gak-gak.
ID text from Wikipedia, CC BY-SA 4.0
Gyrfalcon
Falco rusticolus
The gyrfalcon is the largest falcon in the world, being about the same size as the largest buteos but probably slightly heavier. Males are 48 to 61 centimetres (19 to 24 inches) long, weigh 805 to 1,350 grams (1 pound 12+1⁄2 ounces to 2 pounds 15+1⁄2 ounces), with average weights reported as 1,130 or 1,170 g (2 lb 8 oz or 2 lb 9+1⁄2 oz) and have a wingspan from 110 to 130 cm (43 to 51 in).
ID text from Wikipedia, CC BY-SA 4.0
Learn this pair in the BeakBrain App
Photo and call practice. Coming soon to iPhone and Android.
Play today's Daily BirdPhotos and recordings are credited to their authors under the licence shown. Full profiles: Black Falcon and Gyrfalcon.