escaped probable Saker Falcon x Gyrfalcon hybrid, Choseley (Norfolk, UK), 29th July 2005 - copyright Dave Appleton
(photo ID: 0514)
A large proportion of birds kept by falconers are hybrids, seemingly produced deliberately for reasons that I am yet to fathom. Some are even hybrids of hybrids, with three species involved. Even without factoring in hybrids the identification of some species of falcon is rather difficult and the presence of hybrids makes identification of captive (or escaped) falcons even harder, or often impossible. In my experience the birds' owners are often pretty clueless as to what they have (though they rarely admit it), so asking a falconer is not a reliable way of finding out what something is.
Another thing many falconers seem to be quite poor at is keeping their birds from escaping. Given the way many of them are treated I guess it's no wonder they want to get out, but whatever the reason for it, escaped falcons and other birds of prey are frequently observed in the wild. Many, like the one shown here, carry jesses or bells giving away their captive origin, but many don't.
The bird shown here was present in North Norfolk for a number of months and changed in appearance during its stay. When it was first seen it appeared much darker than shown below and was identified as a Saker. By the time I saw it the underparts especially had become much paler and the bird was almost more likely to be mistaken for a Gyrfalcon than a Saker. The identification is uncertain, but Gyr x Saker is probably a good bet.
escaped probable Saker Falcon x Gyrfalcon hybrid (same bird as in photo ID 0514 above), Choseley (Norfolk, UK), 29th July 2005 - copyright Dave Appleton
(photo ID: 0515)
We are told that the next still-captive bird was three quarters Gyr and one quarter Saker.
captive Saker Falcon x Gyrfalcon hybrid (backcrossed with Gryfalcon), Rowntree Park Birthday Park, York (North Yorkshire, UK), 14th July 2012 - copyright Mark Coates
(photo ID: 2103)
Saker Falcon Falco cherrug
Gyrfalcon Falco rusticolus