Is my species distribution model fit for purpose? Matching data and models to applications

Guillera‐Arroita, Gurutzeta, et al. “Is my species distribution model fit for purpose? Matching data and models to applications.” Global Ecology and Biogeography 24.3 (2015): 276-292. DOI: 10.1111/geb.12268

While Species distribution models are widely used to for ecological, biological and conservation applications, researchers often lack of considerations how fit their data, model output and end-use are. SDM is flexible to be built under different types of species data, how sample process, data type, and modeling approaches influence the use of SDMs is lacking. Guillera-Arroita provided a simple framework that summarizes how interactions between data type and the sampling process may determine the quantity estimated by a SDM. They mainly talked about three types of data: presence-background, presence-absence and occupancy-detection. Our ability to deal with the probability of occupancy, the probability of site being surveyed and species detectability depend on data type being used, and this in turn determines what SDMs can estimate. By reviewing current literature and simulations, they found that even though model predictions fitted the most commonly available data, some requires estimates of occurrence probability, which is only possible with reliable absence data. When converting continuous SDM output to categorical presence/absence, it cannot clearly justify and degrade inference.

 

They claimed a transparent decision-making framework needs to be carried out, and people need to first formulate a clear objective. A critical consideration of using SDM is 1) whether the type of information demanded by the application in question is available, 2) whether the type of data allows unbiased estimation when used in appropriate modeling methods, and 3) thinking about the type of data that a SDM is expected to provide for a given application. This paper raises the attention for SDM users to consider whether the SDM outputs fit their research purposes, especially when continuous-binary conversion needs to be carried out. It would be interesting to see a clear decision-making framework in terms of how this kind of conservation can be justified or how to set the threshold for conversion for different ecological and conservation applications. In addition, efforts are always in demand to develop survey methods that is able to minimize the effects of the sampling process.