ENS BJ (1983) Short announcements: Joint hunting of Hobbies Falco subbuteo. LIMOSA 56 (2): 59-59.

A description is given of joint hunting of two immature Hobbies for small' passerines migrating over the Engelsmanplaat (a sandbank in the Waddenzee) on 5 September 1982. The Hobbies awaited the passerines on the ground. Each hunt started by an attack of one of the Hobbies from below, the second Hobby immediately taking over as soon as the victim escaped the first attack. If the victim escaped again by gaining height the Hobbies switched to attacking from above. Except for a Willow Warbler Phylloscopus trochi/us that escaped, attacked passerines could not be identified, but fresh remains were found of two Robins Erithacus rubecula and two Redstarts Phoenicurus phoenicurus. Three out of fourteen hunts ended successfully, which is low (Bijlsma 1980). Either the birds, being immature, were not very skilful, or given the abundance of prey gave up quickly because it was not profitable to continue chasing once the surprise attack had failed. Eurasian Hobby Falco subbuteo

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