B1179
Title: Finite mixtures in capture-recapture surveys for modelling residency patterns in marine wildlife populations
Authors: Pierfrancesco Alaimo Di Loro - LUMSA University (Italy) [presenting]
Marco Mingione - University of Roma Tre (Italy)
Luca Tardella - Sapienza University of Rome (Italy)
Giovanna Jona Lasinio - Sapienza University of Rome (Italy)
Daniela Silvia Pace - Sapienza University of Rome (Italy)
Gianmarco Caruso - University of Cambridge (United Kingdom)
Abstract: The aim is to show how prior knowledge about the structure of a heterogeneous animal population can be leveraged to improve its abundance estimation from capture-recapture survey data. We combine the Open Jolly-Seber (JS) model with finite mixtures and propose a parsimonious specification tailored to the residency patterns of the common bottlenose dolphin. We employ a Bayesian framework for our inference, discussing the appropriate choice of priors to mitigate label-switching and non-identifiability issues, commonly associated with finite mixture models. We conduct a series of simulation experiments to illustrate the competitive advantage of our proposal over less specific alternatives. The proposed approach is applied to data collected on the common bottlenose dolphin population inhabiting the Tiber River estuary (Mediterranean Sea). Our results provide novel insights into this populations size and structure, shedding light on some of the ecological processes governing its dynamics.