High-resolution species distribution modelling of two coastal biogenic habitat-forming species in an Ecologically and Biologically Significant Area of the Bay of Fundy, Canada

High-resolution species distribution models (SDMs) were developed for two benthic invertebrate species of marine conservation significance across a 113 km2 Ecologically and Biologically Significant Area (EBSA) of the Bay of Fundy, Canada. The stalked tunicate, Boltenia ovifera, and horse mussel, Modiolus modiolus, can form coastal biogenic habitat and are vulnerable to disturbance. A near-seabed imaging survey (depths ranging from 8 to 79 m) provided presence, absence, and abundance data for both species. Boosted Regression Tree SDMs combined these data with 11 environmental variables. Presence-probability distributions were generated; however, abundance patterns could not be adequately modelled. Oblique geographic coordinates, which incorporate location of samples as information, proved useful for predicting species presence, along with seabed rugosity, maximum current speed and bathymetry for B. ovifera, and maximum and minimum current speed along with seabed rugosity for M. modiolus. High-resolution SDMs (in this case, 5-m grid) provide enhanced spatial context for ocean managers towards marine spatial planning in high-use coastal marine environments where bottom contact fisheries access and other coastal development must be balanced against marine conservation objectives.