Date of Award

Spring 2019

Document Type

Open Access Thesis

Degree Name

Master of Science (MS)



First Advisor

Jeff Walker

Second Advisor

Chris Maher

Third Advisor

Terry Theodose


Climate change and weather affect the phenology of bird migration; however, specific climatological factors associated with these observed effects have only recently been described. The relationship between local, regional, and global climate patterns and avian migration are increasingly important to understand due to the widespread, and potentially negative, implications (such as reduced fecundity) of rapid human induced climate change on bird populations. Migratory birds are under selective pressure to arrive at breeding areas at the optimal time to set up nesting territories and exploit seasonally abundant food resources, and because climate change has the potential to occur more rapidly than species can adapt to their migratory behavior, negative impacts to populations may occur as a result of climate change. Human-induced climate change is a driving factor in changing migration phenology, but the effects may be cofounded by endogenous controls and changing conditions among migratory routes. However, despite strong endogenous controls, long-distance migratory birds can alter the timing and rate of migration in response to a changing climate. In this thesis I explore the relationship between spring migration penology and climate.

The literature review addresses the relationships between a changing climate and corresponding changes in avian migration phenology. I summarize the current state of understanding of how anthropogenic climate change is affecting spring migration. The literature documents a clear change in the spring migrant arrival dates over time. To more thoroughly explore these relationships I present the results of a quantitative data modeling exercise that models the variation of migration phenology of birds in Maine. A model selection approach was used to develop a predictive model of spring migrant arrival dates. I demonstrate that, as documented in literature, many passerine species in Maine are arriving increasingly earlier in the spring, as documented in the literature in other regions. Migration strategy, foraging behavior, and pressure from exogenous and endogenous controls affect migration phenology, but I demonstrate that anthropogenic climate change has caused an advancement of median spring arrival times in Maine.