Sara Kross

1 Introduction Anthropogenic landscape change alters not only where animals move but also how they interact (Hoover and Tylianakis 2012; Doherty et al. 2021). Intraspecific interactions are shaped by spatial and behavioral processes that together govern where individuals are located over space and time and how they respond to conspecifics (Whitehead 2008; Webber et al. 2023; Gaynor et al. 2024).

1 INTRODUCTION North American bird populations have dramatically declined during the past five decades (Rosenberg et al., 2019). Whereas the majority of these decreases have been attributed to habitat loss and degradation, collisions with buildings and other human-made structures are recognized as a significant source of mortality and a major threat to the conservation of bird populations (Loss et al., 2015; Rosenberg et al., 2019).

Microplastic has been reported in every major open ocean and many freshwater lakes and rivers. Its small size makes it bioavailable to thousands of species across nearly all trophic levels. Because of the difficulty of large-scale cleanup, environmental managers, scientists, and environmentalists have stressed that the best solution to microplastic pollution is source reduction. Recently, one source of microplastic has received much attention in the media and from policy makers: plastic microbeads.