Simple or hybrid? The performance of next generation ecological models
to study the response of Southern Ocean species to changing
environmental conditions
Abstract
Ecological modelling is widely used in the various fields of ecology but
models usually require large datasets, a serious limitation to the
approach for application to organisms of remote and little studied
regions such as polar seas. Correlative and mechanistic modelling
approaches are usually used independently in distinct studies. Using
both approaches in integrative, hybrid models however can help better
estimate the species realised niche, as mechanistic and correlative
models complement each other very well, giving more insights into
species potential response to fast changing environmental conditions. In
this study, we implemented for the first time an hybrid, correlative and
mechanistic model to predict the response of a marine invertebrate
endemic to the Southern Ocean, the sea urchin Abatus cordatus (Verrill,
1876). We compared the respective performance of simple and hybrid
models by analyzing the effect of seasonality on species distribution, a
key feature of ecosystem functioning at high latitudes. Higher
performances were obtained for the ‘integrated Bayesian’ approach
compared to simple mechanistic and correlative models. The hybrid model
more precisely predicts the effect of seasonality on habitat
suitability. Such results are promising and show that hybrid approaches
can be applied to case studies for which limited datasets are available.