BLANDING’S TURTLES
O ne of the most unexpected things that happened when acting ecologist team lead Julia Phillips began to track the two-year-old, captive-bred Blanding’s turtles released into Ontario’s Rouge National Urban Park is that they led her to adult turtles she hadn’t known about. Until then, monitoring efforts by the nearby Toronto Zoo over 10 years had revealed the presence of only six adults in an area that historically was thought to be excellent habitat. Now, affixed with radio transmitters, the turtles are helping biologists such as Phillips map how Blanding’s turtles use their habitat, in addition to understanding how well they’re surviving in the wild. So far, 165 Blanding’s turtles have been released in the park as part of a joint effort between Parks Canada, the Toronto Zoo and the Toronto Region Conservation Authority to help return healthy populations of this threatened species to its former range. Scientists call palm-sized turtles “head starts,” as they are nourished and protected for two years at the Toronto Zoo in order to give them the best chance of survival when released. “We want them to be big enough that they won’t be bitesized for a fish or passing raccoon,” says Phillips. The park has an over-abundance of predators such as skunks and raccoons that are “subsidized” by access to garbage in the surrounding suburban area. Protecting the head starts from predation, along with ongoing restoration of their wetland habitat, are keys to rebuilding the turtle population. The tracking data, meanwhile, has revealed patterns that will help Phillips and her colleagues better protect the turtle population as it grows. For example, the turtles appear to use a railway corridor as an “easy pathway” from one type of habitat to another. “Turns out, we may need to think about ramps to get them off the railway track,” she says. It’s one of many considerations that will likely come up over the course of what will be a very long project. The turtles can live at least 80 years. Females won’t reach sexual maturity until they are roughly 18. “We have to follow them through to reproductive maturity,” says Phillips, “and make sure they are nesting and having babies before we could consider our job done.”