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Turtle nesting habitat can be created as a restoration strategy to increase habitat availability or provide suitable habitat away from threats. Traditional nest habitat restoration consists of creating nesting mounds using a mix of sand and gravel. However, nesting mounds do not resemble natural turtle nesting habitat in a rock barren landscape where turtles nest in crevices and cracks in the bedrock. Therefore, our objective was to design and evaluate the success of a landscape‐appropriate design for turtle nesting habitat in a rock barren landscape. To evaluate success of the nest habitat design, we assessed the (1) survival of transplanted moss and lichen cover on created nest sites, (2) ecohydrological and physical conditions at created and natural sites, and (3) turtle egg hatching success at created and natural sites using a split‐clutch experiment. We found no difference in productivity between lichen transplants and natural sites, indicating that intact lichen transplants were successful. Moss transplant success was more variable due to moisture stress because transplants were conducted during dry conditions. In general, created nest habitat tended to have a more stable thermal and moisture regime compared to natural sites. When accounting for maternal effects, the odds of an egg hatching successfully was 6.6 times higher in a created site than a natural site. Overall, the success of our nest habitat design in the first few years suggests that this landscape‐appropriate design will be a useful restoration strategy for increasing turtle nesting habitat in rock barren landscapes. [ABSTRACT FROM AUTHOR]

Energy absorption and flow through a nest is an important aspect of embryonic development in many reptile species including turtles. To date, few studies have explicitly attempted to quantify the energy flow through turtle nests, opting instead for the simplified approach offered by temperature index models. However, the quantification of the energy can provide an explicit abiotic link that can link biological models to biometeorological and ecohydrological processes and models. We investigated the energy flow through turtle nests occupying different bedrock morphologies within a Canadian Shield Rock Barren landscape, in Ontario, Canada. The taxons studied were Spotted Turtle (Clemmys guttata), Midland Painted Turtle (Chrysemys picta marginata), and Blanding's Turtle (Emydoidea blandingii). Nest temperature and soil moisture were measured in 2018 and 2019 using sensors placed in the soil adjacent to 12 turtle nest cavities. Three main rock morphologies were identified for each nest location, Crevice, Ledge, and Flat types, that are in order of decreasing bedrock percentage contact with the nest site. Ground heat flux and change in heat storage were determined using the calorimetric method for each nest, while the direction of energy flux between the atmosphere and the underlying rock was also determined. The Crevice nest morphology experienced the lowest ground heat flux on average (1.56 × 10−1 W m−2) and lowest cumulative heat storage (230 MJ) compared to the Flat (440 MJ) and Ledge (331 MJ) nests. However, over the diurnal cycle, large heat gains by Flat nests were mostly balanced out by nighttime heat losses. While Crevice nests saw the lowest daily heat storage gains, they experienced much lower heat losses over the evening period compared to the other nest types. Furthermore, we found that 59% of the energy is directed from the underlying bedrock into the Crevice nest, highlighting the importance of the bedrock in controlling thermal dynamics in the turtle nesting habitat. The lower variability in energy parameters for Crevice nest types can be attributed to higher amounts of nest‐to‐bedrock contact, compared to the flat nest types. Our results indicate that Crevice morphology may be ideal for turtles nesting at their northern limits because minimal heat loss during the evening can result in a more stable thermal incubation environment. Future conservation and habitat restoration efforts should consider the importance of bedrock morphology and prioritize the protection of Crevice nest sites. Furthermore, this work highlights important opportunities for potential interdisciplinary work between ecologists, climatologists, biologists, and hydrologists, specifically the integration of ecohydrological and biological models. This work also underscores the potential uncertainty of climate change impacts on turtle egg hatching success and nest sex ratios. [ABSTRACT FROM AUTHOR]

Lichens and mosses are among the first organisms to colonize the open bedrock of eastern Georgian Bay, Ontario making them essential for primary soil formation and ecosystem succession, while also providing nesting habitat for turtle species‐at‐risk. However, the slow growing nature of lichen and moss makes them vulnerable to ecohydrological stresses caused by climate and land‐use change. In order to better understand how lichen and moss will respond to stressors, we examined which ecohydrological factors (e.g., near‐surface soil moisture and temperature) control the CO2 exchange of lichen (Cladonia spp.) and moss (Polytrichum spp.) on rock barrens, and the time of year growth primarily occurs. Net ecosystem productivity (NEP) was significantly greater in the wet period of the growing season than the dry, with an estimated difference of 0.7 μmol m−2 s−1 for lichen, 2.9 μmol m−2 s−1 for moss, and 2.5 μmol m−2 s−1 for a moss and lichen mix. These findings indicate that the wet portions of the growing season are critical for growth, while lichen and moss have little to no productivity during the dry period. Our results indicate that near‐surface soil moisture is an indicator of the CO2 exchange of lichen and moss, and this relationship varies among cover types. For the geographical regions where warm, dry conditions are expected to increase in duration and frequency with climate change, lichen and moss NEP will likely decrease, thus limiting the long‐term availability of nesting habitat for turtle species‐at‐risk. [ABSTRACT FROM AUTHOR]

Natural wildfire regimes are important for ecosystem succession but can have negative ecological effects depending on fire characteristics. A portion of a granite rock barrens landscape that extends along the eastern shoreline of Georgian Bay, Lake Huron to eastern Ontario, Canada, burned in 2018 during a wildfire that affected >11,000 ha. This landscape is a biodiversity hotspot providing habitat for many species at risk where freshwater turtles nest in soil deposits in cracks and crevices in the bedrock dominated by moss (Polytrichum spp.) and lichen (Cladonia spp.) cover. To assess the initial effect of wildfire on freshwater turtle nesting habitat, we measured soil depths and estimated moss, lichen, and vascular plant cover at 2 morphology types (crevice, flat) in burned and unburned areas of the landscape. The probability that burned flat plots supported soil was near zero; the burned flat plots had 98% less soil volume compared to unburned flat plots. Although crevices were more resistant to soil loss, burned crevices still had a 15% lower probability of having soil and 35% less soil volume compared to unburned crevice plots. We estimated nest site availability by calculating the number of locations with shallow (5–10 cm), intermediate (10–20 cm), and deep (>20 cm) soils required for a small (5 cm × 5 cm) or medium (10 cm × 10 cm) nest chamber. Overall, the burned open rock barrens had 71–73% fewer sites with suitable soil depth and volume for a nest chamber of either size. Furthermore, burned plots had almost no lichen and moss cover but were dominated by bare soil, forbs, and jack pine (Pinus banksiana) seedlings. Although the loss of tree cover in previously forested areas may increase nest site availability for freshwater turtles in newly open areas, we suggest that organic soil combustion and soil erosion may require restoration activities in the post‐fire landscape to support successful nesting of at‐risk turtles. © 2020 The Wildlife Society. After an 11,000‐ha fire in a rock barrens landscape, the availability of nesting habitat for freshwater turtles was lower at burned compared to unburned sites, and the suitability of remaining potential nest sites was likely negatively affected through alterations in soil properties. Extensive organic soil combustion and soil erosion, leading to loss and alteration of nesting habitat, may require restoration activities in post‐fire landscapes to support successful nesting of at‐risk turtles. [ABSTRACT FROM AUTHOR]

Roads are one of the most widespread human‐caused habitat modifications that can increase wildlife mortality rates and alter behavior. Roads can act as barriers with variable permeability to movement and can increase distances wildlife travel to access habitats. Movement is energetically costly, and avoidance of roads could therefore impact an animal's energy budget. We tested whether reptiles avoid roads or road crossings and explored whether the energetic consequences of road avoidance decreased individual fitness. Using telemetry data from Blanding's turtles (Emydoidea blandingii; 11,658 locations of 286 turtles from 15 sites) and eastern massasaugas (Sistrurus catenatus; 1,868 locations of 49 snakes from 3 sites), we compared frequency of observed road crossings and use of road‐adjacent habitat by reptiles to expected frequencies based on simulated correlated random walks. Turtles and snakes did not avoid habitats near roads, but both species avoided road crossings. Compared with simulations, turtles made fewer crossings of paved roads with low speed limits and more crossings of paved roads with high speed limits. Snakes made fewer crossings of all road types than expected based on simulated paths. Turtles traveled longer daily distances when their home range contained roads, but the predicted energetic cost was negligible: substantially less than the cost of producing one egg. Snakes with roads in their home range did not travel further per day than snakes without roads in their home range. We found that turtles and snakes avoided crossing roads, but road avoidance is unlikely to impact fitness through energetic expenditures. Therefore, mortality from vehicle strikes remains the most significant impact of roads on reptile populations. [ABSTRACT FROM AUTHOR]

ABSTRACT: European common reed (Phragmites australis; common reed) is an aggressive invader of North American wetlands that forms homogenous patches and replaces native flora. Dense patches of common reed generally provide poor habitat for many species, although specific effects on at‐risk turtles are largely unknown. We created 3 predictive scenarios to relate the amount of common reed in the landscape to amount of effective habitat for Blanding's turtles (Emydoidea blandingii) and investigated the spatial ecology of 46 adult Blanding's turtles using Euclidean distance analysis within 2 wetland complexes in southern Ontario, Canada. At the home‐range scale, we identified a positive association between turtle home ranges and common reed. At the individual scale, turtle radio‐locations were significantly farther from common reed patches than from random points, consistent with the hypothesis that they avoided common reed patches locally. When we analyzed habitat selection by sex, results were similar to population‐level results except for nesting females. During nesting migrations, females did not avoid common reed patches at the individual scale but instead interacted with common reed, potentially placing themselves at risk of being stranded within dense patches. Our results are consistent with our dynamic home range plus saturation hypothesis that invasion of common reed reduces the amount of effective habitat for at‐risk turtles in wetlands because Blanding's turtles significantly avoided common reed patches at individual scales. Management of common reed is an important step to restore habitat for Blanding's turtles and future research is needed to determine best restoration practices. © 2018 The Wildlife Society. [ABSTRACT FROM AUTHOR]

ABSTRACT One of the deadliest roads in North America for species at risk fragments a marsh-lake ecosystem. To reduce road mortality, stakeholders installed >5 km of exclusion fencing along a southwestern Ontario, Canada, causeway in 2008-2009. Between 2012 and 2014, 7 culverts were installed to provide safe crossings. We evaluated the success of these mitigation strategies by 1) comparing results of road surveys conducted 5 years before and 5 years after fencing installation; and 2) monitoring use of culverts by turtles using motion-activated cameras at culvert openings and stationary antennas placed to detect movements of passive integrated transponder (PIT)-tagged turtles (68 Blanding's turtles [ Emydoidea blandingii] and 30 spotted turtles [ Clemmys guttata]). We also radio-tracked 30 Blanding's turtles to measure culvert use in relation to home ranges. Turtle and snake abundance was 89% and 53% lower, respectively, in completely fenced road sections than in unfenced sections; abundance was 6% and 10% higher, respectively, between partially fenced and unfenced sections. After mitigation, locations where we found reptiles on the road were associated with fence ends, underscoring the importance of fence integrity and ineffectiveness of partial fencing as a mitigation strategy. We confirmed use of culverts by Blanding's turtles, northern map turtles ( Graptemys geographica), snapping turtles ( Chelydra serpentina), and midland painted turtles ( Chrysemys picta). Through radio-tracking, we determined that male and female Blanding's turtles home ranges overlapped with different segments of the causeway. We recommend that stakeholders emphasize ensuring fence integrity and continuity, limiting impact of edge effects, and conducting a comprehensive monitoring program. © 2017 The Wildlife Society. [ABSTRACT FROM AUTHOR]

In central Ontario, Canadian Shield rock barrens are a dominant geographic feature supporting at‐risk reptiles near their northern range limit. To better understand the characteristics of the organic soil that make Canadian Shield rock barrens suitable turtle nesting habitat, we measured moisture retention and evaporative potential and calculated the thermal properties of lichen (Cladonia) mats and moss (Sphagnum and Polytrichum) cushions, as well as their underlying mineral–organic soils. The upper soil profile consisted almost entirely of low density (14–49 kg m−3), high porosity (72–98%) organic matter (loss on ignition [LOI] of 84–99%), which transitioned rapidly to comparatively high density (304–815 kg m−3) mineral–organic soil (LOI of 10–85%). In contrast to Sphagnum and Cladonia, under laboratory conditions, Polytrichum was able to maintain an evaporation rate well above the open‐water potential for several days during a drying experiment. Overall, contrasts in composition and water retention between soil layers are likely to dampen diurnal temperature fluctuations. However, differences in potential water loss between species will have a direct impact on soil thermal dynamics, particularly if substantial water loss occurs in the mineral–organic layer. Because soil depth and temperature regulation by moisture content and soil composition are an important component of nesting habitat, this research provides evidence for the need to conserve moss/lichen‐dominated habitats within turtle species' home ranges. Understanding the ecohydrological controls and limits to how these key moss/lichen species develop and influence primary peat formation represents a critical research need for habitat restoration strategies. [ABSTRACT FROM AUTHOR]