Category: Accipitriformes

Energetic expenditure of male Ospreys provisioning natural and manipulated broods.

Western Osprey (Pandion haliaetus) Science Article 2 abstract This study examined the relationship between brood size and energetic expenditure of male Ospreys. The daily energetic expenditure (DEE) of male Ospreys, provisioning nestlings and providing post-fledging parental care, was estimated using detailed time-energy budgets. Factors affecting DEE were investigated, and DEE and the maximum rate of […]

Courtship Feeding And Osprey Reproduction

Western Osprey (Pandion haliaetus) Science Article 1 abstract A female Osprey (Pandion haliaetus) usually is fed exclusively by its mate between pair formation and egg-laying. Laying dates and courtship periods, but not clutch size, egg size, breeding success or female weight reserves, were correlated (negatively) with the prelaying feeding rates of 12 females breeding in […]

The occurrence of fault bars in the plumage of nestling Ospreys.

Western Osprey (Pandion haliaetus) Science Article 3 abstract We document the occurrence of fault bars in a population of nestling Ospreys Pandion haliaetus under natural conditions. Ospreys had an average of 9.9 fault bars on their rectrices, however variation was large. Fault bar formation declined linearly with age and increased symmetrically from outer to inner […]

Pre-Nesting Behavior Of The Swallow-Tailed Kite (Elanoides Forficatus), Including Interference By An Unmated Male With A Breeding Pair

Swallow-tailed Kite (Elanoides forficatus) Science Article 2 abstract Snyder( 1974) has described the breeding biology of the Swallow-tailed Kite (Elanoides forficatus). My observations of their pre-nesting behavior, made while staying at the Archbold Biological Station at Lake Placid, Florida, confirm his on copulations,courtship feeding, and nest-building Lawrence Kilham, Raptor Research 14(1):29-31 Download article download full […]

Siblicide In Swallow-Tailed Kites

Swallow-tailed Kite (Elanoides forficatus) Science Article 1 abstract We studied the reproductive behavior of Swallow-tailed Kites (Elanoides forficatus) in northern Guatemala. Modal clutch size was two (range l-2), but no nests succeeded in fledging more than one young. RICHARD I? GERHARDT, Wilson Bull., 109(l), 1997, pp. 112-120 Download article download full text (pdf)