title: The implementation of rare events logistic regression to predict the distribution of mesophotic hard corals across the main Hawaiian Islands.
abstract: Predictive habitat suitability models are powerful tools for cost-effective, statistically robust assessment of the environmental drivers of species distributions. The aim of this study was to develop predictive habitat suitability models for two genera of scleractinian corals (Leptoserisand Montipora) found within the mesophotic zone across the main Hawaiian Islands. The mesophotic zone (30-180 m) is challenging to reach, and therefore historically understudied, because it falls between the maximum limit of SCUBA divers and the minimum typical working depth of submersible vehicles. Here, we implement a logistic regression with rare events corrections to account for the scarcity of presence observations within the dataset. These corrections reduced the coefficient error and improved overall prediction success (73.6% and 74.3%) for both original regression models. The final models included depth, rugosity, slope, mean current velocity, and wave height as the best environmental covariates for predicting the occurrence of the two genera in the mesophotic zone. Using an objectively selected theta ("presence") threshold, the predicted presence probability values (average of 0.051 for Leptoseris and 0.040 for Montipora) were translated to spatially-explicit habitat suitability maps of the main Hawaiian Islands at 25 m grid cell resolution. Our maps are the first of their kind to use extant presence and absence data to examine the habitat preferences of these two dominant mesophotic coral genera across Hawai'i.
authors.affiliation: Department of Biology, University of Hawaii at Manoa , Honolulu , HI , United States.
authors.forename: Lindsay M
authors.initials: LM
authors.lastname: Veazey
authors.affiliation: School of Ocean and Earth Science and Technology, University of Hawaii, Hawaii Institute of Marine Biology , Kaneohe , HI , United States.
authors.forename: Erik C
authors.initials: EC
authors.lastname: Franklin
authors.affiliation: The Hawaii Undersea Research Lab, University of Hawaii at Manoa , Honolulu , HI , United States.
authors.forename: Christopher
authors.initials: C
authors.lastname: Kelley
authors.affiliation: Joint Institute for Marine and Atmospheric Research, University of Hawaii at Manoa , Honolulu , HI , United States.
authors.forename: John
authors.initials: J
authors.lastname: Rooney
authors.affiliation: Department of Geology and Geophysics, University of Hawaii at Manoa , Honolulu , HI , United States.
authors.forename: L Neil
authors.initials: LN
authors.lastname: Frazer
authors.affiliation: Hawaii Institute of Marine Biology, University of Hawaii at Manoa , Kaneohe , HI , United States.
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Toonen
keywords: Hawaii; Leptoseris; Mesophotic; Montipora; Predictive modeling; Rare events corrected regression; Scleractinian corals; Species distribution model; Theta threshold selection