Predators of the choughs include the peregrine falcon, golden eagle and Eurasian eagle-owl, while the common raven will take nestlings.
In northern Spain, red-billed choughs preferentially nest near lesser kestrel colonies; the falcon, which eats only insects, provides a degree of protection against larger predators, and the chough benefits in terms of a higher breeding success.
The red-billed chough is occasionally parasitised by the great spotted cuckoo, a brood parasite for which the Eurasian magpie is the primary host.

The choughs host bird fleas, including two Frontopsylla species which are Pyrrhocorax specialist.
Other parasites recorded on choughs include a cestode Choanotaenia pirinica, and various species of chewing lice in the genera Brueelia, Menacanthus and Philopterus.
Blood parasites such as Plasmodium have been found in red-billed choughs, but this is uncommon, and apparently does little harm.
Parasitism levels are much lower than in some other passerine groups.
Predators of the choughs include the peregrine falcon, golden eagle and Eurasian eagle-owl, while the common raven will take nestlings. In northern Spain, red-billed choughs preferentially nest near lesser kestrel colonies; the falcon, which eats only insects, provides a degree of protection against larger predators, and the chough benefits in terms of a higher breeding success. The red-billed chough is occasionally parasitised by the great spotted cuckoo, a brood parasite for which the Eurasian magpie is the primary host.
The choughs host bird fleas, including two Frontopsylla species which are Pyrrhocorax specialist. Other parasites recorded on choughs include a cestode Choanotaenia pirinica, and various species of chewing lice in the genera Brueelia, Menacanthus and Philopterus. Blood parasites such as Plasmodium have been found in red-billed choughs, but this is uncommon, and apparently does little harm. Parasitism levels are much lower than in some other passerine groups.
Chough