Mark-resighting analysis of a California gull population

Journal of Applied Statistics
By: , and 



California gulls (Larus californicus) of known age and sex were censused on their breeding colony in 1979, 1980 and 1984 through 1993. Ages of 235 males and 196 females ranged from 4 to 27 years. Age classes used in the analysis were limited to 17, 4 through 19, and 20 or more as a final age category because data on gulls over 20 were sparse. Survival declined with age in a way that was parsimoniously modelled with a quadratic function. Other factors, sex and time, did not explain any variation in survival. Resighting depended on age, sex and time. Younger adults skipped breeding more frequently than did older adults, and females skipped breeding more frequently than did males. There was also good evidence for time dependence in resighting probability, but its inclusion in the model occurred at the expense of interpretability and precision. In a data set such as this, resighting probability may assume more importance than a mere 'nuisance parameter'. In this study, resighting history measured attendance at the breeding ground. In turn, attendance rates may be a manifestation of reproductive strategy, which can also have consequences for survival. In this situation, there may be heterogeneity in both survival and resighting probability that is unexplained by the model. While such complexity may well be a nuisance to deal with, it can also point to important biological questions.

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Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Mark-resighting analysis of a California gull population
Series title Journal of Applied Statistics
DOI 10.1080/02664769524504
Volume 22
Issue 5-6
Year Published 1995
Language English
Publisher Taylor & Francis
Contributing office(s) Patuxent Wildlife Research Center
Description 15 p.
First page 625
Last page 639
Country United States
State Wyoming
County Albany County
Other Geospatial Bamforth Lake