| Summary: | [ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI--COLUMBIA AT REQUEST OF AUTHOR.] Greater white-fronted geese (Anser albifrons) are Arctic-nesting waterfowl with breeding ranges distributed throughout the Arctic. Due to this broad distribution, the species has been separated into four to five subspecies, and comprises at least eight populations with distinct migration strategies. There are three populations in North America: the Pacific Flyway, midcontinent, and Tule white-fronted geese. The Pacific Flyway and midcontinent populations have both exhibited increases in recent decades. In contrast, the Greenland white-fronted goose population is of conservation concern, and has shown a declining trend over the past 25 years. Greenland white-fronted geese show analogous characteristics in size and breeding biology to North American white-fronted geese, but recent modeling has indicated that recruitment is limiting population growth in the Greenland population. However, researchers have not yet robustly quantified if low recruitment is the result of decision-making (restraint), or external factors, such as local weather conditions experienced during spring migration (constraint). Therefore, we chose the North American midcontinent and Greenland populations, which exhibit contrasting migration strategies, to investigate behavioral decisions and subsequent reproductive output. xii In many populations, individual fitness can be explained by carry-over effects, which are events occurring earlier in the annual cycle that impact individuals later in the year. Carry-over effects are often manifested as body condition effects in migrating waterfowl, whereby individual decisions result in differential condition that explains reproductive success or failure. Carry over effects can be a result of weather conditions. For example, weather-driven decreases in available resources can affect body condition. Advances in Global Positioning System/accelerometer technologies have vastly increased opportunities for researchers to obtain ...
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