Urbanization is a major threat to biodiversity and is occurring at an ever-growing rate. Wildlife living in urban environments experience different conditions than those in rural or natural environments, including higher temperatures, different types and numbers of predators, and higher concentrations of chemical pollutants. Although these urban conditions pose challenges to wildlife, some species persist and even thrive in cities. Behavior is the front line of an animal’s response to its environment. To understand how animals respond to urbanization, it is essential to explore how their behavior changes in cities, and whether these behavioral changes help them successfully survive and raise their young.
This project aims to contribute to our understanding of how features of cities affect animal behavior and reproduction, using the Black Phoebe, a small, insect-eating songbird, as a model system. Our objectives are as follows.
- Assess how Black Phoebes living in urban areas differ in their behavior, including aggressiveness, exploration, and foraging strategies, from those in non-urban areas, and whether differences in behavior are related to reproductive success (number of young successfully raised).
- Investigate links among habitat characteristics (e.g., canopy cover, presence of native vs. non-native vegetation, proximity to water), adult and nestling diet, and nestling growth.
- Examine how high temperatures, predator activity, and exposure to chemical pollutants affect the amount of care provided to young, foraging strategies, and reproductive success of Phoebes, and whether urban-living Phoebes are more tolerant of these conditions than their non-urban counterparts.
To achieve these objectives, we will locate Black Phoebe nests in urban parks and nature preserves, track nesting attempts, and measure Phoebe behavior in a variety of situations, including how much time they spend taking care of their nestlings and where they look for food. We will also characterize features of the habitat around each nest, record predator sightings, and continuously monitor temperature near all nests. Finally, we will small samples of Black Phoebe feathers to learn about their Black Phoebe diet!
Our research will provide insight into how different aspects of the urban environment (e.g., high temperatures, exposure to predators, habitat characteristics) limit or promote the persistence of birds in cities. If we can understand the factors governing the Black Phoebe’s ability to survive and reproduce in cities, we may be able to use this information to improve urban quality of life for native birds and to understand why other species (such as closely related flycatchers) may be struggling to adapt. Additionally, our investigation of interactions between urbanization and heat will provide key insight into how the combination of multiple forms of global change—urbanization and climate change—will affect birds and will thus help inform conservation and management of birds in an increasingly human-modified world.