Publications

Scales, KL; Hazen, EL; Jacox, MG; Edwards, CA; Boustany, AM; Oliver, MJ; Bograd, SJ (2017). Scale of inference: on the sensitivity of habitat models for wide-ranging marine predators to the resolution of environmental data. ECOGRAPHY, 40(1), 210-220.

Abstract
Understanding and predicting the responses of wide-ranging marine predators such as cetaceans, seabirds, sharks, turtles, pinnipeds and large migratory fish to dynamic oceanographic conditions requires habitat-based models that can sufficiently capture their environmental preferences. Marine ecosystems are inherently dynamic, and animal-environment interactions are known to occur over multiple, nested spatial and temporal scales. The spatial resolution and temporal averaging of environmental data layers are therefore key considerations in modelling the environmental determinants of habitat selection. The utility of environmental data contemporaneous to animal presence or movement (e.g. daily, weekly), versus synoptic products (monthly, seasonal, climatological) is currently debated, as are the trade-offs between near real-time, high resolution and composite (i.e. synoptic, cloud-free) data fields. Using movement simulations with built-in environmental preferences in combination with both modelled and remotely-sensed (ROMS, MODIS-Aqua) sea surface temperature (SST) fields, we explore the effects of spatial and temporal resolution (3-111 km, daily-climatological) in predictive habitat models. Results indicate that models fitted using seasonal or climatological data fields can introduce bias in presence-availability designs based upon animal movement datasets, particularly in highly dynamic oceanographic domains. These effects were pronounced where models were constructed using seasonal or climatological fields of coarse (>0.25 degree) spatial resolution. However, cloud obstruction can lead to significant information loss in remotely-sensed data fields. We found that model accuracy decreased substantially above 70% data loss. In cloudy regions, weekly or monthly environmental data fields may therefore be preferable. These findings have important implications for marine resource management, particularly in identifying key habitats for populations of conservation concern, and in forecasting climate-mediated ecosystem changes.

DOI:
10.1111/ecog.02272

ISSN:
0906-7590