Environmental Challenges to Avian Populations: A Physiological Perspective

Many environmental challenges currently affect bird populations negatively. For instance, rising global temperatures can lead to heat stress and cause severe physical damage and animal welfare challenges, as well as impact resource availability for both wild and commercial avian species. In addition, many populations are affected by urbanization and its associated habitat degradation, fragmentation, and/or elimination. Most urbanized areas also experience higher temperatures (heat island effect) than surrounding non-urbanized habitats, as well as elevated levels of noise and light pollution. The intake of pollutants produced by agricultural, industrial, and urban activities can also cause avian morbidity and mortality. Many studies have already investigated the correlates of environmental challenges on various aspects of avian physiology such as the reproductive system, stress and immune responses, metabolism, thyroid function, and developmental profile, but a large number of important questions remain unanswered. In particular, information on these topics is often available for a relatively small number of avian taxa that differ greatly phylogenetically and ecologically, making it difficult to generalize conclusions. In addition, most studies are correlative rather than causative. As a result, we still know relatively little about the physiological impact of specific environmental factors on avian physiology, interactions between these factors, and the extent to which their effects are age, sex, and/or physiological condition-related. In most cases it also remains unknown whether the observed negative effects of environmental factors on the physiology of birds are phenotypic (i.e., plastic and potentially reversible) or reflective of genetic or epigenetic adaptations. Addressing these questions is urgent and of fundamental importance. Indeed, environmental degradation continues unabated and at a rapid rate worldwide, and research on its biological effects, mechanisms of action, and consequences is critical to mitigate its negative consequences on both wild and domesticated biological communities, preserve biodiversity, and ensure the sustainability of poultry production, especially in geographical areas where “backyard” flocks are the main source of animal proteins and are inherently dependent on environmental conditions.

To address the above issues, this Research Topic welcomes Brief Research, Mini Review, Opinion, Original Research, Perspective and Review article types, among others, on, but not limited to, the following suggested themes: The effects of light, air, noise, soil, and chemical pollution on avian physiology and survival; feed availability and contamination (e.g., toxins, heavy metals, PCB) and its effects on avian physiology; solutions to the above that include new and innovative protocols to mitigate threats in this area. Articles under this Research Topic will constitute a major advance to the field by including contributions from scientists who investigate questions at various levels – ecosystem to genetics -, combine and integrate correlative and experimental studies, work in a variety of ecosystems, and use diverse experimental models.