Larger structural size is typically viewed as a positive individual trait assumed to benefit survival chances and overall fitness. For territorial species, increased structural size relative to conspecifics could aid with obtaining a territory, finding a mate, and territorial defense. We explore this dynamic in a hemispheric migrant, Swainson's hawk (Buteo swainsoni), which exhibits strong breeding and natal philopatry. Previous research from the Butte Valley breeding population has shown that average natal dispersal was 9 km in the mid-1990s, and has remained constant, despite the population doubling. From 2009 to 2018, over 800 individual Swainson’s hawks were marked as nestlings; of those, 111 (55 females, 56 males) were later observed breeding within the boundaries of our long-term study area. From previous work we know nestlings that are recruited into the local population are structurally larger than those never resighted. . We also know that females will disperse farther than males. Given these population observations, we hypothesize that nestling structural size influences natal dispersal distance, age of recruitment, and quality of territory obtained. We predict that relatively smaller recruits will have larger natal dispersal distances, recruit at older ages, and be relegated to less productive territories.

Lizzi grew up in rural Colorado and moved to Northern California over a decade ago to attend Humboldt State University where she completed a B.S. in Wildlife Conservation Biology. She has researched habitat use of mesocarnivores, impacts of anthropogenic landscape change on osprey nesting success and nest site selection, and blood parasites in osprey nestlings. She is dedicated to mentoring early career professionals and students whenever possible. Lizzi works as a wildlife biologist for Dudek, an employee-owned environmental consulting firm. She is also currently an NSF Graduate Research Fellow joining the Johnson Habitat Ecology Lab at Cal Poly Humboldt to continue one of the longest running raptor projects in North America, the Butte Valley Swainson's Hawk project, for her graduate studies.