Separating mortality and emigration: modelling space use, dispersal and survival with robust-design spatial-capture-recapture data

1. Capture-recapture (CR) techniques are commonly used to gain information about population dynamics, demography and life-history traits of populations. However, traditional CR models cannot separate mortality from emigration. Recently developed spatial-capture-recapture (SCR) models explicitly incorporate spatial information into traditional CR models, thus allowing for individuals’ movements to be modelled explicitly. 2. In this paper, we extend SCR models using robust-design data to allow for both processes in which individuals can disappear from the population, mortality and dispersal, to be estimated separately. We formulate a general robust-design spatial capture-recapture (RD-SCR) model, explore the properties of the model in a simulation study, and compare the results to a Cormack-Jolly-Seber model and a non-spatial robust-design model with temporary emigration. In the case study, we fit several versions of the general model to data on field voles (Microtus agrestis) and compare...