| Summary: | We used video cameras to identify nest predators at active shorebird and passerine nests and conducted point count surveys separately to determine species richness and detection frequency of potential nest predators in the Prudhoe Bay region of Alaska. From the surveys, we identified 16 potential nest predators, with glaucous gulls (Larus hyperboreus) and parasitic jaegers (Stercorarius parasiticus) making up more than 80% of the observations. From the video evidence, however, we identified arctic foxes (Alopex lagopus) as the predators in five of six predation events recorded with the cameras. These results indicate that estimated abundances of predators alone may not accurately reflect their true or proportional importance as nest predators. We also found that the identified predators removed all eggs and left the nests intact. Thus, attempts to identify predators solely on the basis of nest remains are not reliable for smaller bird species in this region. We found no evidence that camera-monitored nests were at greater risk of predation or desertion than camera-free nests. Overall, our ability to film predation events was hampered by the brief, highly synchronized breeding season, the harsh climate, and the higher nest survivorship for shorebirds in this region relative to temperate-breeding passerines, which have been the focus of most studies that use camera systems in attempts to identify nest predators at active nests. Nous avons recouru à des cameras vidéo pour repérer les prédateurs de nids actifs d’oiseaux de rivage et de passériformes, puis nous avons effectué des calculs séparément afin de déterminer la richesse des espèces et la fréquence de détection de prédateurs de nids potentiels dans la région de la baie de Prudhoe, en Alaska. À partir des calculs, nous avons dénombré 16 prédateurs de nids potentiels, les goélands bourgmestres (Larus hyperboreus) et les labbes parasites (Stercorarius parasiticus) représentant plus de 80 % des observations. Cependant, à partir des vidéos, nous avons pu ...
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