Moving in the Right Direction: Using Spatial Ecology to Evaluate Release Methods for an Imperilled Freshwater Turtle in an Urban Landscape

ABSTRACT Aquatic ecosystems and species are under threat due to anthropogenic impacts, prompting implementation of conservation strategies. Headstarting is a strategy that involves rearing vulnerable life stages (e.g., eggs and hatchlings) in human care until they are large enough to reduce mortality risk after release. Many reintroductions fail because animals released into new environments often experience an acclimation period manifesting as short‐term increases in mortality or dispersal. To improve reintroduction outcomes, additional support (e.g., use of soft release) could be provided to headstarted animals in the release environment. Using data collected from a headstarting programme on the globally endangered Blanding's turtle ( Emydoidea blandingii ) in Toronto, Ontario, Canada, we tested whether headstarted turtles experienced an acclimation period and whether release types affected movement patterns and home‐range sizes. We used two release types: a hard release, where headstarted turtles were released directly into the wetland, and a type of soft release, where headstarted turtles were penned for 7 days without supplemental food or protection from predators and then released (i.e., delayed‐release). From 2014 to 2020, the mean daily distance travelled (m) by headstarted turtles ranged 0.61–19.62 m, and the annual home‐range size ranged 0.002–6.77 ha. Headstarted turtles in both release groups had similar mean daily distance travelled and home‐range size at release and 6 years post‐release. Furthermore, there was no evidence of an acclimation period in either metric, indicating that release type did not influence movement patterns. Our study highlights the need for long‐term monitoring of headstarted animals and the importance of testing common assumptions of release types in the context of reintroductions.