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Full-Text Articles in Ornithology
Thermal Constraints On Foraging Activity Of Adult Starlings, Larry Clark
Thermal Constraints On Foraging Activity Of Adult Starlings, Larry Clark
Larry Clark
The operative temperature of the environment was estimated for starlings using hollow, unheated taxidermic mounts. On average, adults foraging in full sun were characterized by shorter foraging bouts than those adults foraging in full shade. Simultaneous observations of air temperature, operative temperature, and the foraging duration of adults indicated that air temperature was a poor predictor of the maximum length of a foraging bout. The operative temperature of the environment was not correlated to the maximum and mean length of foraging bouts for temperatures below 31.5 ~ C, but was negatively related to maximum and mean foraging duration for values …
Use Of Nest Material As Insecticidal And Anti-Pathogenic Agents By The European Starling, Larry Clark, J Russell Mason
Use Of Nest Material As Insecticidal And Anti-Pathogenic Agents By The European Starling, Larry Clark, J Russell Mason
Larry Clark
Passerine birds that reuse nest sites face an increased parasite and pathogen load. They also are more likely to use fresh green vegetation during nest construction. The present results demonstrate that at least one passerine, the European Starling: (a) selects a small subset of available plant species for inclusion in nest material; and (b) chooses plants whose volatiles are more likely to inhibit arthropod hatching and bacterial growth relative to a random subset of available vegetation. The results also show that preferred plants possess greater numbers of mono- and sesqueterpenes at higher concentrations relative to a random subset of available …
Consequences Of Homeothermic Capacity Of Nestlings On Parental Care In The European Starling, Larry Clark
Consequences Of Homeothermic Capacity Of Nestlings On Parental Care In The European Starling, Larry Clark
Larry Clark
The homeothermic capacity of chicks varied as a function of brood size, age, and air temperature. Commitment to rooding by parents also varied as a function of brood size, age of the young brooded, and prevailing air temperature. It was experimentally determined that parents altered their brooding commitment in direct response to the achieved mean homeothermic capacity of the brood rather than energy demands of the brood per se. Because larger broods achieved a given level of homeothermic capacity earlier than smaller broods, parents spent less time brooding larger broods. This "freed" time represented an increase in potential foraging time …
Nest Site Selection By The Red-Tailed Tropicbird, Larry Clark, Robert Ricklefs, Ralph Schrieber
Nest Site Selection By The Red-Tailed Tropicbird, Larry Clark, Robert Ricklefs, Ralph Schrieber
Larry Clark
-Red-tailed Tropicbirds (Phaethon rubricauda) nest under shrubs in loosely associated groups on Christmas Island, Central Pacific Ocean. Aggressive interactions among adults at nest sites are high; yet, large areas of superficially similar habitat contain no tropicbird nests at all. We compared physiognomic features of nest sites with those of two sets of randomly generated "nest sites" by discriminant function analysis. Of those variables measured, the number of stems within a nest space and the amount of peripheral cover influenced the tropicbirds' choice of nest sites. Differences among localities existed. Areas where tropicbirds nested had shrubs with few stems and more …