The protection of natural lands is vital for conservation of biodiversity however, protection of lands alone is not always sufficient for maintaining historic species diversity. A tight spatial coupling between wetland and terrestrial habitat is critical for a diverse range of herpetofauna to successfully carry out life activities. For instance, turtles require terrestrial habitat for nesting and estivation, some snakes hibernate on land, and after breeding, some anurans will move upland to forage and overwinter. In addition to wetlands, many reptiles and amphibians rely on adjacent terrestrial habitat. Herpetofauna depend on diverse wetland habitat for breeding, foraging, and winter refugia. Reptiles and amphibians, collectively referred to as herpetofauna, have experienced recent global population declines frequently linked to habitat loss, fragmentation, and degradation. In addition, habitat loss and fragmentation can isolate critical habitats or entire populations (e.g., ), reduce genetic diversity (e.g., ), decrease the potential for rescue effects (e.g., ), and result in local species extinctions. Landscape change through fragmentation and the direct loss of habitat prohibits or significantly impairs species’ ability to carry out critical life activities such as foraging, overwintering, and breeding. This is important because, while habitat succession is a natural process, succession and changes can affect landscape suitability either positively or negatively depending on the target species. Identification of long-term trends in habitat changes may elucidate drivers of ecological processes, and therefore, help understand mechanisms of landscape changes. However, this decision-making process benefits from understanding the historic landscape and tracking long-term environmental changes. Many ecosystems have become increasingly composed of a mix of historical and novel habitats, making it difficult to evaluate future conservation actions and resource management strategies. The rate of landscape change and the extent at which it affects species-at-risk has escalated since the onset of the Anthropocene. Our results suggest that long-term landscape changes resulting from habitat succession and invasive species can negatively affect habitat suitability for herpetofauna and protection of land alone does not necessarily equate to protection of sensitive herpetofauna. Restoration of the northwestern region and tip of Point Pelee National Park to a mixed landscape of shallow wetlands (cattail, graminoid, forb, open water) and eradication of dense Phragmites stands should improve habitat diversity. Loss of open habitats such as savanna and meadow has reduced availability of high quality thermoregulation habitat for reptiles. Reduced diversity of marsh habitats appears to be linked to the expansion of invasive Phragmites australis, which invaded prior to 2000. The marsh matrix transitioned from a graminoid and forb shallow marsh interspersed with water to a cattail dominated marsh, altering critical breeding, foraging, and overwintering habitat. Marsh habitat diversity and aquatic connectivity has declined since 1931. Change-detection analyses were used to evaluate the relative importance of proportionate loss and fragmentation of 17 habitat types. To track habitat changes we used aerial image data spanning 85 years (1931–2015) and manually digitized and classified image data using a standardized framework. We hypothesized that long-term changes in availability and distribution of critical habitat types may have contributed to the disappearance of herpetofauna. Point Pelee National Park, located at the southern-most tip of Canada’s mainland, historically supported a large number of herpetofauna species however, despite nearly a century of protection, six snake and five amphibian species have disappeared, and remaining species-at-risk populations are thought to be in decline.
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