caa a22 4500 465782078 CHVBK 20180323111958.0 cr unu---uuuuu 170327e19900301xx s 000 0 eng 10.1007/BF00172085 doi (NATIONALLICENCE)springer-10.1007/BF00172085 Brunton Dianne School of Natural Resources, University of Michigan, 48109-1115, Ann Arbor, Michigan, MI, USA aut The effects of nesting stage, sex, and type of predator on parental defense by killdeer ( Charadrius vociferous ): testing models of avian parental defense [Elektronische Daten] [Dianne Brunton] Summary: Two models predicting the temporal patterns of parental investment in offspring defense over the nesting cycle were tested. The first is based on offspring age, the other on the vulnerability of offspring to predation. Both models make very similar predictions for altricial species after eggs have hatched, i.e., increases in intensity of parental defense until fledging. For precocial species, however, the post-hatching predictions of each model are different: the offspring age model predicts a continued increase in defense intensity, while the vulnerability model predicts a decline. I examined the temporal patterns of parental defense of a precocial shorebird, the killdeer (Charadrius vociferus), and determined which model was supported. Killdeer responses to human and natural predators were observed. Killdeer were less willing to leave the nest, responded most intensely, and displayed closest to a potential predator around hatching. Defense intensity increased from early to late incubation as predicted by the offspring age model. However, after hatching killdeer parental defense declined for both males and females, thus supporting the vulnerability model for this stage. Males and females responded significantly differently to all types of predators. Males took greater risks, remained on the nest longer, defended offspring more intensely, and displayed closer to the predator than females at the approach of a potential predator. Responses to natural predators depended on the type of predator and the approach made by the predator; a greater range of defense behavior was used for predators approaching on the ground compared to aerial predators. In general, killdeer responses to humans were more intense and less variable than their responses to natural predators. This was most likely because the human intruder approached nests and chicks more directly and closer than natural predators. Springer-Verlag, 1990 Behavioral Ecology and Sociobiology Springer-Verlag 26/3(1990-03-01), 181-190 0340-5443 26:3<181 1990 26 265 https://doi.org/10.1007/BF00172085 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00172085 text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Brunton Dianne School of Natural Resources, University of Michigan, 48109-1115, Ann Arbor, Michigan, MI, USA aut NATIONALLICENCE 773 0- Behavioral Ecology and Sociobiology Springer-Verlag 26/3(1990-03-01), 181-190 0340-5443 26:3<181 1990 26 265 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer