The diet of the Lanner (Falco biarmicus) in a hyper-arid region of the eastern Sahara

Abstract

The contents of regurgitated Lanner ( Falco biarmicus ) pellets and other food remains collected at four sites in the hyper-arid Darb el Arba'in Desert, southwestern Egypt, are analysed. A total of 791 bones were identified from the remains, representing a minimum of 108 individuals of 19 species of migratory birds. Quail ( Coturnix coturnix ) comprised 50% of the total number of individuals identified and 34% of the total biomass, and turtle dove ( Streptopelia turtur ) 19–4% and 19%, respectively. The balance of the other 17 species each made up less than 5% of the total number of individuals taken. No other vertebrate order was represented in the remains. It appears that Lanners arrive on the nesting grounds and commence breeding in mid-February. This allows them to utilise the massive movement of birds passing over the area between April and early May; this migration coincides with the period the falcons need to feed nestlings. During the initial stages of nesting, when few bird migrants are passing through the area, the adults feed almost exclusively on locust ( Schistocerca gregaria ).