From habitat suitability to species distribution: complementarity of ecological and biogeographical objects in the context of global change
Matthieu VIGNAL, Avignon Université - UMR CNRS 7300 ESPACE, France
Julien ANDRIEU, Université Côte d'Azur - UMR CNRS 7300 ESPACE, France
Global change (e.g., global warming and land-use/land-cover changes) should have significant effects on species abundance and distribution (IPBES, 2019). Identifying endangered species is therefore a major challenge for implementing relevant conservation and protection policies.
Several models have been developed to this end, with the aim of projecting species’ ecology into space and time (Franklin, 2010). Based on the ecological niche concept, these models analyse species' distribution across environmental gradients and determine species habitat suitability (Peterson et al., 2011; Guisan et al., 2017). However, a species is not necessarily present in all the suitable areas. Therefore, depending on the species’ characteristics (common or rare, generalist or specialist), the suitable areas for the species could provide rough information about its distribution.
Thus, the aim of this study is to develop a method for mapping species distribution, e.i., species abundance within suitable areas. To do this, the method is based on (1) habitat suitability modeling, (2) abundance data collection, and (3) species abundance modeling using the Hurdle model (Cragg, 1971).
The Hurdle model's results reflect both the study area's occupancy rate and the local abundance of the species under consideration. The findings imply that the Hurdle model may be used to reproduce the various spatial structures of species distribution from the macro to micro-regional scales, as well as the spatial heterogeneity of populations at the local scale.
Species abundance, as current distribution, provide additional information compared to habitat suitability, but these two objects remain complementary. Indeed, the confrontation of these two objects allows the identification of species’ endangered populations and thus a better estimation of current issues in the global change context. This study thus illustrates the complementarity between these two objects, and thus between ecology and biogeography.
Mots clés : Global change|Habitat suitability|Species distribution|Species Abundance Models
A104387MV