Seven of Canada’s eight native freshwater turtle species are at risk. Wildlife Preservation Canada has been working on the problem since 2004, when we launched a research project into nesting success in two of Ontario’s largest, most important turtle nesting areas. This research showed that, even though the nesting sites were in prime, protected habitat inside national and provincial parks, virtually 100% of all turtle nests were being destroyed within 48 hours of being laid!
The culprit? Natural predators such as raccoons and skunks, whose populations have been given a boost beyond natural levels due to inadvertent subsidization by human campers and cottagers. The implications are staggering but help explain why many of Ontario’s turtle populations, in both urban and rural areas, consist primarily of older adults. Anywhere there are people, there are subsidized populations of raccoons and other omnivorous nest predators. There aren’t any young turtles because the eggs are not even making it to the hatchling stage.
Ontario Turtle Recovery
Since 2005, Wildlife Preservation Canada’s freshwater turtle program has supported research and conservation strategies that reduce nest failures and protect nests and eggs from mammalian predation. Starting in 2005, MSc. and then PhD candidate Ryan Bolton used motion-activated cameras at night to identify raccoons and skunks as the main predators, followed by opossums and coyotes. Ryan’s project trialed a variety of mitigation techniques over the years including: in situ protection using wire cages placed directly over nests, relocation of nests to large-scale predator exclosures, moving nests to other locations along beaches used for breeding, and artificial incubation in a lab setting. By 2010 Ryan found that each method has its own inherent pros and cons, but all methods ensure that a large number of nests hatch, and Ryan’s work saved over 4,000 eggs from predation. Since 2011, project leader Christina Davy and her team were able to save and release over 3,000 hatchlings, bringing our all-time total to over 8,000 Blanding’s, northern map, snapping, spiny softshell, and spotted turtle hatchlings saved. These young turtles can now begin the arduous, multi-year journey to maturity. Christina’s project also includes mark-recapture work which allows for direct monitoring of the these threatened populations. Mark-recapture surveys allow changes in population size over time to be detected so that population declines can be investigated and mitigated. As part of her PhD work, Christina researched the conservation genetics of spotted turtles and developing microsatellite markers for spiny softshell and snapping turtles which will be used to assess the genetic diversity and relatedness of at-risk populations.
Quebec and the spiny softshell
For the first time in 2014, we became involved in the conservation of the spiny softshell turtle in Québec. The Lake Champlain population is thought to be disjunct from others and therefore warrants its own recovery efforts. The Québec’s recovery team, created in 1997, is responsible for the orientation and planning of actions related to this species in the province. The Granby Zoo, supported by Wildlife Preservation Canada, is leading the field work component during nesting season. Predation and human disturbance are issues as they are in Ontario, however, flooding of the nesting sites is also very detrimental to the nests survival. In the first years of the team, the main actions have been to: conduct individual monitoring on adult females using telemetry; locate important areas such as hibernacula and nesting sites, and when possible protect or acquire land; create new basking and nesting sites; set up a group of local volunteers; develop and conduct outreach and educational activities. For the seventh consecutive year this 2015 season, eggs will be collected and incubated at the zoo, not very far from the field site. This increases the hatching success from 28 % in the wild to 81 %, and resulted in the release of over 600 juveniles so far.
British Columbia and the western painted turtle
Western Painted Turtle Recovery began in 2006 when the species was first listed. Extensive field work searching for, monitoring, restoring habitat features and establishing priorities propelled the need for the formation of captive rearing or head-starting (2013) and captive breeding (2014-15) programs. These efforts began as a collaborative effort between Wildlife Preservation Canada and Greater Vancouver Zoo. This project, based on previous work done recovering turtle populations in the US, aims to restore turtle numbers at sites at risk of local extirpation, which includes the majority of sites in the South Coast Region. The draft recovery strategy for this species specifically highlights the need for population augmentation and management in its list of recovery objectives: Stabilize or increase recruitment where needed through population management including captive breeding, translocations, and/or head-starting while maintaining the genetic distinctiveness of BC populations (Population management). Population augmentation will help us to effectively increase the population of turtles at sites where population numbers are low or where sex ratios limit or prohibit breeding. By continually addressing threats, maintaining supportive habitat features, monitoring our efforts and of course rearing and releasing turtles we hope to be able to restore this much loved and highly missed species back to the water ways in BC.