Population size and stopover duration estimation using mark-resight data and Bayesian analysis of a superpopulation model.
We present a novel formulation of a mark-recapture-resight model that allows estimation of population size, stopover duration, and arrival and departure schedules at migration areas. Estimation is based on encounter histories of uniquely marked individuals and relative counts of marked and unmarked animals. We use a Bayesian analysis of a state-space formulation of the Jolly-Seber mark-recapture model, integrated with a binomial model for counts of unmarked animals, to derive estimates of population size and arrival and departure probabilities. We also provide a novel estimator for stopover duration that is derived from the latent state variable representing the interim between arrival and departure in the state-space model. We conduct a simulation study of field sampling protocols to understand the impact of superpopulation size, proportion marked, and number of animals sampled on bias and precision of estimates. Simulation results indicate that relative bias of estimates of the proportion of the population with marks was low for all sampling scenarios and never exceeded 2%. Our approach does not require enumeration of all unmarked animals detected or direct knowledge of the number of marked animals in the population at the time of the study. This provides flexibility and potential application in a variety of sampling situations (e.g., migratory birds, breeding seabirds, sea turtles, fish, pinnipeds, etc.). Application of the methods is demonstrated with data from a study of migratory sandpipers.
U.S. Fish and Wildlife Service, Division of Migratory Bird Management, Patuxent Wildlife Research Center, Laurel, Maryland, U.S.A.
James E
JE
Lyons
U.S. Geological Survey, Colorado Cooperative Fish and Wildlife Research Unit, Fort Collins, Colorado 80523, U.S.A.
William L
WL
Kendall
U.S. Geological Survey, Patuxent Wildlife Research Center, Laurel, Maryland, U.S.A.
J Andrew
JA
Royle
U.S. Geological Survey, Patuxent Wildlife Research Center, Laurel, Maryland, U.S.A.
Sarah J
SJ
Converse
U.S. Fish and Wildlife Service, Division of Migratory Bird Management, Denver, Colorado 80225, U.S.A.
Brad A
BA
Andres
Cascadia Research Collective, Olympia, Washington 98501, U.S.A.
Joseph B
JB
Buchanan
D025041:Animal Migration / Q000502:physiology*; D000818:Animals; D001499:Bayes Theorem; D019352:Censuses; D003198:Computer Simulation; D003627:Data Interpretation, Statistical; D015233:Models, Statistical; D011156:Population Density; D011157:Population Dynamics; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
Capture-recapture; Data augmentation; Jolly-Seber; Mark-resight; Migration; State-space model