APPARENT SURVIVAL OF BREEDING WESTERN SANDPIPERS ON THE YUKON-KUSKOKWIM RIVER DELTA, ALASKA

• Main Authors: Johnson, Matthew, Ruthrauff, Daniel R., McCaffery, Brian J., Haig, Susan M., Walters, Jeffrey R.
• Format: Text
• Language: unknown
• Published: DigitalCommons@University of Nebraska - Lincoln 2010
• Subjects: Yukon; Kuskokwim; Alaska
• Online Access: https://digitalcommons.unl.edu/usgsstaffpub/696; https://digitalcommons.unl.edu/context/usgsstaffpub/article/1705/viewcontent/Haig_WJO_2010_APPARENT_SURVIVAL_OF_BREEDING_WESTERN_SANDPIPERS.pdf

We used 8 years of live recapture data (1998–2005) to estimate apparent annual survival for male (n = 237) and female (n = 296) Western Sandpipers (Calidris mauri) breeding on a 36-ha plot on the Yukon-Kuskokwim River Delta, western Alaska. Apparent annual survival (Φ) is the product of true survival and site fidelity, and estimates of Φ were corrected for the probability of encounter. Overall return rates (individual returned to the study site in a subsequent season) were lower for females (40%) than males (65%), as was Φ (± SE, females = 0.65 ± 0.05, males = 0.78 ± 0.03), and encounter rate (females = 0.51 ± 0.07, males = 0.74 ± 0.04). Results differed from previous estimates of Φ for this species as our estimates of Φ were higher for both males and females compared to estimates from another breeding site and two nonbreeding locations. Disparity among Φ estimates from breeding and nonbreeding areas highlights the need to delineate site-specific factors throughout the annual cycle that influence population dynamics of the Western Sandpiper.