Current Ornithology

Abstract

A Continuation Order Plan is available for this series. A continuation order will bring delivery of each new volume immediately upon publication. Volumes are billed only upon actual shipment. For further information please contact the publisber. = Current ornithology. 1. Ornithology-Periodicals. I. Johnston, Richard F. QL671.C87 598'.05-dcl9 84-640616 [8509] AACR 2 MARC-S ISBN 978-1-4757-9920-0 ISBN 978-1-4757-9918-7 (eBook) v PREFACEThis edited series has three principal goals. The first is to provide information in a relatively concise way for researchers needing an overview of specific disciplines. The second is to provide an update on specific schools of thought, bringing together ideas from colleagues whose works often appear in a variety of journals. And the third is to stimulate and suggest directions for new research. Volume 6 continues the tradition established by the previous editor and editorial board in providing new information, updating our understanding of specific disciplines, and stimulating new research. In the first chapter, Randall Breitwisch examines mortality patterns and sex ratios in monogamous birds. He argues that there are many more components to measuring parental investment than are often realized; our knowledge is weak in several areas. Understanding the evolution of mating systems depends on better distinguishing the different intensities of natural selection that operate on males and females. Gregory Butcher and Sievert Rohwer develop a framework for assessing the role of colorfulness in birds. They propose several hypotheses to test and advocate evaluating more than one hypothesis at a time. Future work on the evolution of distinctive coloration and of sexual and age dimorphism must take these ideas into account.Paul Kerlinger and Frank Moore examine the structure of the atmosphere (e.g., thermals, winds, temperature) as it may be relevant to avian migration. They develop the hypothesis that atmospheric structure is an important force in natural selection for timing and altitude of migration. A comparison is made with other presumed selective vii viii PREFACE influences, such as predation and competition. Gabor Lovei of Hungary shares his review of passerine migration between the Palaearctic and Africa, allowing comparisons to be made with the Nearctic-Neotropical system. Geographic barriers for birds migrating from Europe and Asia to Africa are greater than those existing between North and South America; these barriers influence the patterns of passerine migration.Noel and Helen Snyder summarize their knowledge of the biology of the California Condor and the history and issues that led to conservation efforts and capture of the last remaining birds. They reveal the fascinating undercurrent of politics and interactions driving the development of decisions affecting endangered species. The prospects ahead for captive breeding and release of condors in the wild, and the ultimate goals for condor conservation, are addressed. Jerry Waldvogel concludes the volume with an excellent syno...

Nocturnal departure timing in songbirds facing distinct migratory challenges

“…Early departures are probably adaptive for nocturnal migratory flights across a sea barrier, as these allow maximizing the night-time available for flying (Moore & Kerlinger, 1992). In doing so, birds may optimize their exploitation of advantageous nocturnal conditions (laminar air layers (Kerlinger & Moore, 1989), no sun radiation (Schmaljohann et al, 2008), low predation risk (Walter, 1979)) and, hence, maximize the distance covered during the night. These advantages probably act as selective forces shaping the observed temporal pattern of nocturnal departures in general, and in particular when crossing ecological barriers (cf.…”

“…Adamík et al, 2016;DeLuca et al, 2015;Ouwehand & Both, 2016;Schmaljohann, Liechti, & Bruderer, 2007a, 2007b. Nocturnal migration may optimize the time budget (feeding vs. flying) of birds (Alerstam, 2009) and reduce their energetic costs of transport (Kerlinger & Moore, 1989), water loss (Schmaljohann, Bruderer, & Liechti, 2008), and predation risk (Walter, 1979) as compared to diurnal migration. The result is a temporally constrained schedule for migratory movements with the nocturnal departure time influencing the potential duration of a migratory flight.…”