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The ability to uniquely identify individuals is critical to estimating and monitoring trends in population sizes, one of the key metrics used to evaluate a species' conservation status and success of mitigation strategies. For freshwater turtles, shell notching and/or passive integrated transponder (PIT) tags are commonly used to mark individuals. However, because notch codes and PIT tags can be lost over time and require more invasive procedures, we explored if photographs offer an effective method to reliably identify individuals. The Blanding's turtle (Emydoidea blandingii) is a globally endangered species with distinct black and yellow markings on its plastron. We used the I3S Pattern software with custom parameters to classify patterns on Blanding's turtle plastrons and to identify individuals. We analyzed 826 plastron images from 707 individual Blanding's turtles taken between 1998 and 2019 from 12 study areas distributed throughout their Canadian range. When plastron photos were pooled across the sampled range (i.e., all study areas), there was an 84% probability of correctly identifying an individual turtle within the top 3 suggested matches, whereas when identifying Blanding's turtles within a specific study area, identification accuracy was 82% in Central Ontario and 97% in Nova Scotia. Individual identification from plastron markings did not work well in areas where iron staining obscured the plastron pattern or for hatchlings and juveniles whose patterns changed over time. For example, the only misclassification in the Nova Scotia study area was for a turtle with photos through various life stages. In areas without iron staining, plastron photo identification offers a cost-effective, non-invasive method to identify individual adult Blanding's turtles to support population monitoring and community science initiatives, and has the potential to assist with range-wide coordination to counteract illegal wildlife trade. [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]

With recent advances in technology, personal aerial imagery acquired with unmanned aerial vehicles (UAVs) has transformed the way ecologists can map seasonal changes in wetland habitat. Here, we use a multi-rotor (consumer quad-copter, the DJI Phantom 2 Vision+) UAV to acquire a high-resolution (< 8 cm) composite photo of a coastal wetland in summer 2014. Using validation data collected in the field, we determine if a UAV image and SWOOP (Southwestern Ontario Orthoimagery Project) image (collected in spring 2010) differ in their classification of type of dominant vegetation type and percent cover of three plant classes: submerged aquatic vegetation, floating aquatic vegetation, and emergent vegetation. The UAV imagery was more accurate than available SWOOP imagery for mapping percent cover of submergent and floating vegetation categories, but both were able to accurately determine the dominant vegetation type and percent cover of emergent vegetation. Our results underscore the value and potential for affordable UAVs (complete quad-copter system < $3,000 CAD) to revolutionize the way ecologists obtain imagery and conduct field research. In Canada, new UAV regulations make this an easy and affordable way to obtain multiple high-resolution images of small (< 1.0 km2) wetlands, or portions of larger wetlands throughout a year. [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]