0000000000024788

AUTHOR

James D. Nichols

Sources of variation in survival and breeding site fidelity in three species of European ducks

Summary 1  We used long-term capture–recapture–recovery data and a modelling approach developed by Burnham (1993) to test a priori predictions about sources of variation in annual survival rates and fidelity within a population of individually marked females in three species of European ducks from a breeding ground study site in Latvia. 2  True annual survival was higher for diving ducks (tufted duck 0·72, common pochard 0·65) and lower for northern shoveler (0·52). Survival of female diving ducks was positively correlated with mean winter temperatures at Western European wintering areas, the relationship being much stronger for pochard. 3  We present the first unbiased estimates of breedin…

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Factors affecting breeding dispersal of European ducks on Engure Marsh, Latvia

Summary 1 We used up to 35 years of capture–recapture data from nearly 3300 individual female ducks nesting on Engure Marsh, Latvia, and multistate modelling to test predictions about the influence of environmental, habitat and management factors on breeding dispersal probability within the marsh. 2 Analyses based on observed dispersal distances of common pochards and tufted ducks provided no evidence that breeding success in year t influenced dispersal distance between t and t+ 1. 3 Breeding dispersal distances (year t to t+ 1) of pochards and tufted ducks were associated with a delay in relative nest initiation dates in year t+ 1. The delay was greater for pochards (c. 4 days) than for tu…

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Estimating natal dispersal movement rates of female European ducks with multistate modelling

Summary 1 We used up to 34 years of capture–recapture data from about 22 100 new releases of day-old female ducklings and multistate modelling to test predictions about the influence of environmental, habitat and management factors on natal dispersal probability of three species of ducks within the Engure Marsh, Latvia. 2 The mean natal dispersal distances were very similar (c. 0·6–0·7 km) for all three species and were on average 2·7 times greater than breeding dispersal distances recorded within the same study system. 3 We were unable to confirm the kinship hypothesis and found no evidence that young first-nesting females nested closer to their relatives (either mother or sister) than to …

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Quantitative studies of bird movement: a methodological review

The past several years have seen the development of a number of statistical models and methods for drawing inferences about bird movement using data from marked individuals. It can be difficult to keep up with this rapid development of new methods, so our purpose here is to categorize and review methods for drawing inferences about avian movement. We also outline recommendations about future work, dealing both with methodological developments and with studies directed at hypotheses about bird movement of interest from conservation, management, or ecological perspectives.

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