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Anna C. Peterson

Publications and source records attributed to Anna C. Peterson.

2 recordsLinked to original sources

Extending the habitat concept to the airspace

Habitat is one of the most familiar and fundamental concepts in the fields of ecology, animal behavior, and wildlife conservation and management. Humans interact with habitats through their senses and experiences and education to such a degree that their perceptions of habitat have become second nature. For this reason, it may be difficult at first to accept the airspace as habitat, an area that is invisible, untouchable, highly dynamic, and its occupants difficult to see. Nonetheless, the habitat concept, by definition and in practice, applies readily to the airspace. Some ecological and behavioral processes including habitat selection, foraging, and reproduction are operational in the airspace, while others, particularly those mediated by resource limitation such as territoriality, are likely uncommon if present at all. The behaviors of flying animals increasingly expose them to anthropogenic hazards as development of the airspace accelerates. This exacerbates the need to identify approaches for managing these human–wildlife conflicts in aerial habitats, especially where human safety or at-risk populations are concerned. The habitat concept has proven useful in shaping environmental law and policy to help mitigate these conflicts. It remains to be seen whether current law can bend to include a more expansive concept of habitat that includes the airspace.

Book chapter

Patterns in diurnal airspace use by migratory landbirds along an ecological barrier

Migratory bird populations and survival are affected by conditions experienced during migration. While many studies and conservation and management efforts focus on terrestrial stoppage and staging areas, the aerial environment through which migrants move also is subjected to anthropogenic impacts with potential consequences to migratory movement and survival. During autumn migration, the northern coastline of Lake Superior acts as an ecological barrier for many landbirds migrating out of the boreal forests of North America. From 24 observation points, we assessed the diurnal movements of birds throughout autumn migration, 2008-2010, within a 210 km by 10 km coastal region along the northern coast of Lake Superior. Several raptor species showed patterns in airspace associated with topographic features such as proximity to the coastline and presence of ridgelines. Funneling movement, commonly used to describe the concentration of raptors along a migratory diversion line that either prevents or enhances migration progress, occurred only for Bald and Golden Eagles. This suggests a "leaky" migration funnel for most migratory raptors (e.g., migrating birds exiting the purported migration corridor). Passerines migrating during the late season showed more spatial and temporal structure in airspace distribution than raptors, including funneling and an association with airspace near the coast. We conclude that a) the diurnal use of airspace by many migratory landbirds is patterned in space and time, b) autumn count sites situated along ecological barriers substantially underestimate the number of raptors due to 'leakage' out of these concentration areas, and c) the magnitude and structure of diurnal passerine movements in airspace have been overlooked. The heavy and structured use of airspace by migratory landbirds, especially the airspace associated with anthropogenic development (e.g., buildings, towers, turbines) necessitates a shift in focus to airspace management and conservation attention for these animals.

Minnesota