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Article
Barbara Frei, Auteur ; James W. Fyles, Auteur ; Jacob L. Berl, Auteur ; John W. Edwards, Auteur ; Joseph J. Nocera, AuteurABSTRACT The Red-headed Woodpecker (Melanerpes erythrocephalus) is a threatened bird species undergoing continued population declines across most of its range. Despite the conservation concern, there are few published studies on the species? fec[...]
Article
Jacob L. Berl, AuteurDans Wildfowl (63 2013)Behavioural data were recorded from flocks of wintering American Wigeon Anas americana on a southern Californian (USA) golf course to test whether vigilance was related to levels of local human activity. The study site was subject to high rates [...]
Article
Jacob L. Berl, Auteur ; John W. Edwards, Auteur ; Jeffrey S. Bolsinger, Auteur ; Todd E. Katzner, Auteur
Article
Jacob L. Berl, Auteur ; Jeffrey M. Black, AuteurDans Wildfowl (61 2011)Observations were made of feeding American Wigeon Anas americana to assess their vigilance levels in relation to foraging location. American Wigeon increased vigilance levels: 1) while foraging on land compared to on water, 2) while grazing prog[...]
