An integrative approach to regional mapping of suitable habitat for the Blanding’s turtle (Emydoidea blandingii) on islands in Georgian Bay, Lake Huron

Abstract

Mapping suitable habitat for a species at risk is one of the first steps in a conservation plan. Creating habitat suitability maps can be very challenging when the area of interest is large and located in remote areas where field excursions can be difficult to implement. Such is the case for the Blanding's turtle, a threatened species in Ontario, that live on the Georgian Bay archipelago. With increasing anthropogenic pressures, maps indicating suitable habitat can aid management decisions and prioritize areas for protection. We apply an interdisciplinary approach using traditional field data and generalized linear models to produce high resolution, regional maps which identify suitable habitat for Blanding's turtles throughout the archipelago. We assessed the accuracy of our models using an independent survey dataset of 16 island sites distributed throughout the archipelago, and evaluated models using a reference island as a threshold for determining suitability of survey sites. Islands with higher proportions of wetlands and vernal pools were generally considered to be suitable for Blanding's turtles compared to those with lower proportions. Our findings highlight the importance of both permanent and temporary wet habitats for Blanding's turtles. Based on our final model, approximately 64% of evaluated islands support habitat for Blanding's turtles. Our study is the first to produce detailed habitat suitability maps for Blanding's turtles on the Georgian Bay archipelago. We recommend an integrative approach be applied to create habitat suitability maps for other species at risk in Georgian Bay.