Document Type
Honors Thesis
Major
Wildlife Ecology
Advisor(s)
Brian Olsen
Committee Members
Lindsay Seward, Erik Blomberg, Linda Welch
Graduation Year
May, 2025
Publication Date
2025
Abstract
Climate-induced changes in phenological timing is poorly understudied in seabirds compared to passerines, especially differences between short- and long-distance migrants. We examined how climate change, particularly rising sea surface temperatures and climate indices such as ONI and NAO, are influencing the breeding phenology of Arctic and common terns in the Gulf of Maine. Data were collected over the course of 26 years, on six islands within the Maine Coastal Islands National Wildlife Refuge System in Maine, USA. Linear mixed effect models and an AIC model analysis were conducted to show that common terns, a shorter-distance migrant compared to Arctic terns, do, in fact, exhibit a more pronounced shift towards earlier breeding, as their hatch dates shifted more across the past three decades than Arctic terns. Despite this, Arctic terns repeatedly hatched a few days earlier in the breeding season than common terns.
Recommended Citation
Brennan, Elizabeth, "Phenological Changes in Arctic and Common Terns Across Maine’s Coastal Islands" (2025). Honors College. 925.
https://digitalcommons.library.umaine.edu/honors/925