Phase 2 : development of a population model for the Southern Great Barrier Reef green turtle stock

Abstract

A stochastic simulation model was developed for the southern Great Barrier Reef green sea turtle stock to foster better insight into regional metapopulation dynamics. The model was sex- and age class-structured linked by density-dependent, correlated and time-varying demographic processes subject to environmental and demographic stochasticity. The simulation model was based on extensive demographic information derived for this stock from a long-term sea turtle research program established and maintained by the Queensland Parks andWildlife Service. Model validation was based on comparison with empirical reference behaviours and sensitivity was evaluated using multi-factor perturbation experiments and Monte Carlo simulation within a fractional factorial sampling design. The model was designed to support robust evaluation of the effects of habitat-specific competing mortality risks on stock abundance and also on the sex and ageclass structure. Hence, the model can be used for simulation experiments to design and test policies to support the long-term conservation of the southern Great Barrier Reef green sea turtle stock.