Terns usually will aggregate in the same reproduction area during breeding season. The color pattern of eggs may match the background, and it is important for breeding adults to distinguish their own eggs, especially in colonies with high density. This research was carried out at three islands, Huolung Shoal, Baisha and Jishan Islets of Penghu from May to August of 2007 and 2008. The experiment was divided into three parts, egg moving (EM) experiment, nest modification (NM) experiment and egg switching (ES) experiment. Terns spent more time for searching their own nests of each of the experiment situation. In the EM experiment 69.7% Black-naped Tern adults settled on original nests without eggs in 2007; 52.0% Roseate Tern in 2007 and 29.6 % in 2008 did the same. In the NM experiment, the behavior patterns of returning adults were significantly different between each operation and the control group. Adults were confused by the interference of the experimental conditions. In some occasions, adults settled on incorrect eggs quietly in ES experiment. In conclusion, terns have low ability of egg recognition but high ability of nest recognition. Terns presumably can recognize nests with the nearby environmental landmarks, but not be able to recognize eggs.

Expanding populations, more leisure time and increased standards of living since World War II, have resulted in an ever increasing demand in the United States and Canada for outdoor recreation in the form of hunting and fishing... In the course of the investigation it was necessary to census the nesting population, find nests, and search for broods. It was apparent that these observations were important in themselves, and the investigation soon expanded into a study of the ecology of waterfowl in the area, of which, in the end, the orginal objective became a minor part...

Expanding populations, more leisure time and increased standards of living since World War II, have resulted in an ever increasing demand in the United States and Canada for outdoor recreation in the form of hunting and fishing... In the course of the investigation it was necessary to census the nesting population, find nests, and search for broods. It was apparent that these observations were important in themselves, and the investigation soon expanded into a study of the ecology of waterfowl in the area, of which, in the end, the orginal objective became a minor part...

Thesis (M.S.)--Oregon State University, 1988. / Typescript (photocopy). Includes bibliographical references (leaves 60-63). Also available on the World Wide Web.

Zsfassung in dt. Sprache. - Würzburg, Univ., Diss., 2008

Zugl.: Leipzig, Univ., Diss., 2008

Thesis (Ph. D.)--Colorado State University, 2004. / Includes bibliographical references.

American Kestrel Nest Box Programs have been established since the mid 1960’s. The population of American Kestrels (Falco sparverius) along nest box trails has decreased by 47 percent since their original implementation. There are existing technologies that can help in the location of prime kestrel habitat (open fields with conspicuous perching locations) along highways, which reduces the amount of labor in searching for new box locations. These technologies can also help increase the efficiency of monitoring and maintaining kestrel nest trail programs. This study provides an example of how Google Maps can be implemented into a kestrel trail and explains the multiple benefits of the integration.

Nesting success is an important vital rate affecting the reproductive fitness of birds, and predation typically is the single most important factor affecting nesting success. Presumably, birds should nest in locations that maximize nest survival. If specific nest characteristics increase the probability that a nest will hatch, natural (phenotypic) selection could favour use of sites with these features, producing nonrandom patterns of nest site use. Alternatively, birds that are highly selective in nest site choices might be at a disadvantage if predators learn to forage preferentially in these locations and improve their efficiency in depredating nests; in this case, random nesting patterns could be favoured. Finally, it has been hypothesized that predation pressure can influence nest site selection patterns of entire bird communities. If predators develop a search image to hunt for bird nests, then nests that are most similar to each other, irrespective of species, should sustain higher mortality. To evaluate these hypotheses, I quantified nest site selection patterns of multiple species of ground-nesting dabbling ducks in areas where predation pressure was normally high, and compared these patterns to those on areas where predation was relaxed. Predation pressure was experimentally reduced by removing common predators of duck nests and females (mainly red foxes, coyotes, skunks and raccoons) on some study areas and not on others (controls). Predator removal and natural causes produced a 10-fold difference in duck nesting across study sites, allowing for investigation of effects of predation pressure on nest site selection of ducks. Coarse scale habitat selection patterns were similar to results reported in previous studies; blue-winged teal and northern shoveler were found more often in native grassland than in other habitat types, while gadwall and mallard nests occurred more frequently in shrub patches when compared with other habitat patches. A difference in nest site characteristics was observed between hatched and depredated nests for gadwall and northern shoveler but not for blue-winged teal and mallard. However, in all species, the nest site selection patterns were non-random. Thus, the process of nest predation did not shape patterns of nest site choice. Contrary to predictions, inter-specific overlap in nest site features was not related to predation pressure: nests that overlapped most with features of other species did not suffer higher predation, nor did inter-specific overlap in nest characteristics decrease during the nesting season. These findings were inconsistent with the hypothesis that community-level patterns of nest site use are differentiated as a result of predation pressure. Long-term work on nest site use by individually marked females of numerous ground-nesting bird species would be informative, as would experimental studies of other hypotheses about factors affecting nest site choices in birds.

Nesting success is an important vital rate affecting the reproductive fitness of birds, and predation typically is the single most important factor affecting nesting success. Presumably, birds should nest in locations that maximize nest survival. If specific nest characteristics increase the probability that a nest will hatch, natural (phenotypic) selection could favour use of sites with these features, producing nonrandom patterns of nest site use. Alternatively, birds that are highly selective in nest site choices might be at a disadvantage if predators learn to forage preferentially in these locations and improve their efficiency in depredating nests; in this case, random nesting patterns could be favoured. Finally, it has been hypothesized that predation pressure can influence nest site selection patterns of entire bird communities. If predators develop a search image to hunt for bird nests, then nests that are most similar to each other, irrespective of species, should sustain higher mortality. To evaluate these hypotheses, I quantified nest site selection patterns of multiple species of ground-nesting dabbling ducks in areas where predation pressure was normally high, and compared these patterns to those on areas where predation was relaxed. Predation pressure was experimentally reduced by removing common predators of duck nests and females (mainly red foxes, coyotes, skunks and raccoons) on some study areas and not on others (controls). Predator removal and natural causes produced a 10-fold difference in duck nesting across study sites, allowing for investigation of effects of predation pressure on nest site selection of ducks. Coarse scale habitat selection patterns were similar to results reported in previous studies; blue-winged teal and northern shoveler were found more often in native grassland than in other habitat types, while gadwall and mallard nests occurred more frequently in shrub patches when compared with other habitat patches. A difference in nest site characteristics was observed between hatched and depredated nests for gadwall and northern shoveler but not for blue-winged teal and mallard. However, in all species, the nest site selection patterns were non-random. Thus, the process of nest predation did not shape patterns of nest site choice. Contrary to predictions, inter-specific overlap in nest site features was not related to predation pressure: nests that overlapped most with features of other species did not suffer higher predation, nor did inter-specific overlap in nest characteristics decrease during the nesting season. These findings were inconsistent with the hypothesis that community-level patterns of nest site use are differentiated as a result of predation pressure. Long-term work on nest site use by individually marked females of numerous ground-nesting bird species would be informative, as would experimental studies of other hypotheses about factors affecting nest site choices in birds.