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Using migration and navigation as a focus, this chapter looks at the movements of birds. The genetic, hormonal, and physiological control of migration is analysed as are the evolution of migratory strategies and routes. Particular emphasis is given to fuelling migration and the significance of stop-over behaviours during migratory movements. The conservation implications of migration and of movement in general are considered, and the impact upon migratory fuelling of neonicotinoids pesticides are discussed. Sections examining innate and learned route finding and the migratory cues (sun, stars, magnetic field, etc) used by birds to determine their location, and the direction in which they need to travel to arrive at a goal, are given. The role of memory in place finding and food storage is considered, as is the neurology of spatial memory. Techniques used by ornithologists to study bird movement are explained throughout the chapter.

The avifauna of the study area is described and quantified, beginning with historical coverage since 1872. The Van Cortlandt Park cumulative and breeding avifaunas are dissected and contrasted with those of Central and Prospect Parks. Study area breeding species are treated quantitatively, followed by winter species, and migration phenomena; features and conclusions are amplified in 39 tables. The chapter concludes with extended discussion of past and current avian resource problems, particularly in Van Cortlandt Park and what park management is doing about them, with specific recommendations for needed research and management actions.

This book explores the key ecological, biological, physiological, navigational, and evolutionary aspects of migration as it occurs in birds. Using the structure of the annual cycle, it considers how avian migrants differ from their resident counterparts and suggests that these differences represent milestones along the evolutionary pathway that shape a migrant lifestyle through the process of natural selection. This introductory chapter discusses the development of human understanding of migration, the origins of migration, types of migration, patterns of migration within species, and adaptations for bird migration. It also outlines five categories of exaptations that make resident birds possessing them preadapted for migration: life history, movement, navigation, energy storage and use, and timekeeping.

This chapter focuses on the avian migrant's spring transient period, which begins with departure from the wintering area and ends with arrival at the breeding area. The emphasis is on the “reproduction” aspect of the fitness equation rather than the “survival” aspect. This shift in emphasis from survival to reproduction has far-reaching effects on migratory birds' adaptation for movement from nonbreeding to breeding areas. The chapter first considers the bird's preparation for spring departure and goes on to discuss the endogenous factors and distal cues governing the timing of spring departure. It then examines the timing of departure within the spring transient period and within the circadian period, along with the migrant's migratory flight and migration route. It also describes the avian migrants' orientation, navigation, and stopover in spring and concludes by analyzing the impact of climate change on bird migration.

This chapter focuses on the evolution and biogeography of avian migrants. Theories on the origin of migration are generally assigned to one of two categories: “northern home” and “southern home.” This chapter proposes an alternative theory for the origin of migration through dispersal that only requires intraspecific competition for breeding space and a new, reachable environment where competition is less or absent and probabilities of survival and/or reproduction are greater than at the site of origin. It first considers exaptations versus adaptations for migration, along with the genetics of migration, rapid development of bird migration, and migrant population differentiation. It then examines the link between ornithogeography and migration patterns and concludes by providing an overview of the world's principal migration systems.

This chapter analyses the scientific practices involved in the study of a highly mobile research object: birds. More in particular it studies the transformation in bird study brought about by the foundation of ornithological observatories around 1900. The focus is on the field station of Rossitten, East Prussia. This observatory, the first of its kind, was founded in 1901 and was led, for the first three decades of its existence, by the minister, hunter and practical naturalist Johannes Thienemann. The innovations that Thienemann introduced in ornithology called for specific spatial strategies. These included an optimal use of the natural characteristics of his workplace and the mobilization of a large network of geographically scattered amateurs. At the same time, his work altered the space he shared with the birds – materially, conceptually and culturally. Thienemann’s station proved a crucial tool both in changing ornithology and Rossitten.

There are numerous sources of data relevant for studies of the effects of climate change. Here we provide a classification of such data and their advantages and drawbacks. Long-term data can be classified into data from long-term population studies, nest record schemes, bird surveys, breeding and winter atlases, bird ringing information, bird ringing stations, bird observation depositories, and museum collections. Such data differ enormously in quality, but also in their usefulness. They range from long-term population studies of individually banded birds that can be used for genetic, evolution, and ecology studies to studies of presence/absence data. There are relatively few individual-based population studies while databases of records of individuals are much more abundant, albeit still useful for many purposes. Different databases also vary consistently in data quality, and there is scope for methodological studies and comparative analyses of multiple data bases.

This chapter demonstrates that the Arctic is not an evolutionary freezer. The fauna and flora show much variation both within and between species. The driving force that creates biological diversity, however, is predominantly physical and due to variations in the environment. There is still competition for optimal sites for nesting and feeding in birds and mammals, just as there is between plants for sheltered and stable sites. Nevertheless, it is the thermal conditions that eventually determine survival. The chapter discusses pre-adaptation for arctic survival; Arctic evolutionary influences; evolution of seasonal bird migrations; plant diversity and evolution at high latitudes; Arctic and boreal mammal lineages; and human evolution at high latitudes.

This chapter discusses four important ways in which human and migrant ecology interact. The first is the impact of migrant agricultural pests, especially locusts. Various monitoring and pest management techniques have been instituted to mitigate the impact of locusts on agricultural systems in different parts of the world. The second example is the relation between infectious disease and migration. There has been much speculation but little evidence concerning whether migrants transmit diseases to humans and livestock. There is evidence that confining migrants can increase disease incidence. The third example concerns salmon populations in California and the commercial fishery. Poor water management and damming of rivers has reduced salmon populations below commercial levels with considerable economic costs. Finally, there is discussion of climate change with respect to bird migration. In this case the extensive movements of birds make assessment difficult. The nature of climate change effects and implications for avian migrants are at present uncertain, although suggestions of change are apparent in some cases.

This chapter highlights the author's field notes from the Golden Gate Raptor Observatory (GRRO). A hawkwatcher with the GGRO commits to a rotation during the fall migration, basically mid-August to early December, participating on a team at least one day every other week. The author's team has an exceptional level of experience. The training was rigorous, but the GGRO style was reassuring. The rule for beginners is “When you see a hawk, start to talk.” They had to learn not only the field marks of the nineteen species they might encounter, but also the local topography, where every landmark goes by a distinct name. As a general rule, the more northerly the winds, the better the hawkwatching. The birds, after all, are heading south, and most of them are smart enough to avoid migrating into a headwind whenever possible. The author was especially interested in raptors and ferruginous hawks.