Terrestrial or marine species distribution model: Why not both? A case study with seabirds.

Henry Häkkinen,William J Sutherland,Silviu O Petrovan,Nathalie Pettorelli

doi:10.1002/ece3.8272

Henry Häkkinen, William J Sutherland + Show 2 more

Open Access

https://doi.org/10.1002/ece3.8272

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Abstract

Species reliant on both the terrestrial and marine realms present a challenge for conventional species distribution models (SDMs). For such species, standard single‐realm SDMs may omit key information that could result in decreased model accuracy and performance. Existing approaches to habitat suitability modeling typically do not effectively combine information from multiple realms; this methodological gap can ultimately hamper management efforts for groups such as seabirds, seals, and turtles. This study, for the first time, jointly incorporates both terrestrial information and marine information into a single species distribution model framework. We do this by sampling nearby marine conditions for a given terrestrial point and vice versa using parameters set by each species’ mean maximum foraging distance and then use standard SDM methods to generate habitat suitability predictions; therefore, our method does not rely on post hoc combination of several different models. Using three seabird species with very different ecologies, we investigate whether this new multi‐realm approach can improve our ability to identify suitable habitats for these species. Results show that incorporating terrestrial information into marine SDMs, or vice versa, generally improves model performance, sometimes drastically. However, there is considerable variability between species in the level of improvement as well as in the particular method that produces the most improvement. Our approach provides a repeatable and transparent method to combine information from multiple ecological realms in a single SDM framework. Important advantages over existing solutions include the opportunity to, firstly, easily combine terrestrial and marine information for species that forage large distances inland or out to sea and, secondly, consider interactions between terrestrial and marine variables.

Highlights

Species distribution models (SDMs) are a widely used method in ecology to describe, predict, and project species ranges (Engler et al, 2017; Loiseau et al, 2020; Mod et al, 2016; Robinson et al, 2017)
If a species has both a marine range and a terrestrial range, and both terrestrial and marine variables are important, the logical step is to include both realms in a single model framework
Our results demonstrate that the addition of marine variables to terrestrial species distribution models (SDMs), or vice versa, improves the accuracy of SDMs for multi-realm species, in both specificity and sensitivity

Summary

| INTRODUCTION

Species distribution models (SDMs) are a widely used method in ecology to describe, predict, and project species ranges (Engler et al, 2017; Loiseau et al, 2020; Mod et al, 2016; Robinson et al, 2017). Other studies have proposed to build two separate marine and terrestrial SDMs and subsequently combine them, similar in logic to a multi-niche or seasonal niche approach (Engler et al, 2014; Nakazawa et al, 2004) This “joining” process can be done in several ways, such as by summing or averaging suitability for each cell (Frans et al, 2018; Gschweng et al, 2012), a “nearest neighbor” approach (Gherghel et al, 2020; Russell et al, 2015) or a “moving window” approach (Frans et al, 2018). We assessed the interactions and relative importance of marine and terrestrial variables on seabird distributions during the breeding season

| MATERIALS AND METHODS

Findings

| DISCUSSION