| Abstrak/Abstract |
The expensive computational cost of sensitivity analyses has hampered the use of these techniques for
analysing individual-based models in ecology. A relatively cheap computational cost, referred to as the
Morris method, was chosen to assess the relative effects of all parameters on the model’s outputs and to
gain insights into predator–prey systems. Structure and results of the sensitivity analysis of the
Sumatran tiger model – the Panthera Population Persistence (PPP) and the Notonecta foraging model
(NFM) – were compared. Both models are based on a general predation cycle and designed to
understand the mechanisms behind the predator–prey interaction being considered. However, the
models differ signi?cantly in their complexity and the details of the processes involved. In the
sensitivity analysis, parameters that directly contribute to the number of prey items killed were found
to be most in?uential. These were the growth rate of prey and the hunting radius of tigers in the PPP
model as well as attack rate parameters and encounter distance of backswimmers in the NFM model.
Analysis of distances in both of the models revealed further similarities in the sensitivity of the two
individual-based models. The ?ndings highlight the applicability and importance of sensitivity analyses
in general, and screening design methods in particular, during early development of ecological
individual-based models. Comparison of model structures and sensitivity analyses provides a ?rst step
for the derivation of general rules in the design of predator–prey models for both practical conservation
and conceptual understanding. |
