Multiscale determinants of Pacific chorus frog occurrence in a developed landscape.

Pacific chorus frog (Pseudacris regilla) populations have persisted despite urban and rural development throughout the species' range; yet it is possible that P. regilla, like other anurans with which it historically co-occurred, will become extirpated from cities and suburbs if urbanization intensifies as predicted. An improved understanding of the conditions that enable this species to persist in developed landscapes is needed to identify and conserve suitable habitats. We investigated species-habitat relationships for P. regilla in a mixed urban-rural landscape in southwestern British Columbia, Canada, to identify potential criteria for habitat suitability. We conducted repeat auditory surveys of chorusing males at 52 potential breeding wetlands and modeled occupancy at 26 of these sites using local and landscape variables representing competing hypotheses and spatial scales of influence. The models that best explained P. regilla occupancy included a combination of terrestrial habitat and connectivity factors and the presence of non-native predators. We found that the proportion of impervious cover within 250 m of a wetland had the strongest negative impact on occupancy. Our findings suggest that availability of terrestrial habitat adjacent to breeding sites is the primary driver of species presence in the developed landscape. Conservation efforts should seek to limit impervious cover to less than 20% within a 250-m buffer around breeding wetlands. Further, restored and created wetlands in urban and rural areas may be more likely to support P. regilla if they are designed with a seasonal hydroperiod that excludes non-native aquatic predators and are placed in an area of high pond density.

Publisher Correction: A century of high elevation ecosystem change in the Canadian Rocky Mountains.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

A century of high elevation ecosystem change in the Canadian Rocky Mountains.

Mountain ecosystems serve as sentinels of change, and those in the Canadian Rocky Mountains have undergone a pronounced shift over the past century. We present quantitative analyses of 81 high-resolution image pairs of systematic historic surveys and repeat photographs of Canadian Rocky Mountain habitats, measuring treeline advance, changes in tree density, and shifts in growth form from krummholz to trees. With a time-lapse of 68 to 125 years (mean 93.5 years) between image pairs, these photographs contain novel information about long-term ecological change across broad spatial scales. In the 197 linear km of mountain habitat over 5 degrees of latitude examined, we found evidence of treeline advance at 90/104 sites, increases in tree density at 93/104 sites, and many sites (79/95) showing detectable changes in the growth form of trees from krummholz to erect tree form. Using generalized linear mixed models, we found that treeline at higher altitudes and further north had a greater probability of advancing while regional climate factors in our model did not significantly explain our results. Historic references, such as those documented here, are invaluable for providing conservation targets and for contextualizing disturbance and broad scale ecosystem change.

A criteria and indicators monitoring framework for food forestry embedded in the principles of ecological restoration.

Food forestry is a burgeoning practice in North America, representing a strong multifunctional approach that combines agriculture, forestry, and ecological restoration. The Galiano Conservancy Association (GCA), a community conservation, restoration, and educational organization on Galiano Island, British Columbia in Canada, recently has created two food forests on their protected forested lands: one with primarily non-native species and the other comprising native species. These projects, aimed at food production, education, and promotion of local food security and sustainability, are also intended to contribute to the overall ecological integrity of the landscape. Monitoring is essential for assessing how effectively a project is meeting its goal and thus informing its adaptive management. Yet, presently, there are no comprehensive monitoring frameworks for food forestry available. To fill this need, this study developed a generic Criteria and Indicators (C&I) monitoring framework for food forestry, embedded in ecological restoration principles, by employing qualitative content analysis of 61 literature resources and semi-structured interviews with 16 experts in the fields of food forestry and ecological restoration. The generic C&I framework comprises 14 criteria, 39 indicators, and 109 measures and is intended to guide a comprehensive and systematic assessment for food forest projects. The GCA adapted the generic C&I framework to develop a customized monitoring framework. The Galiano C&I monitoring framework has comprehensive suite of monitoring parameters, which are collectively address multiple values and goals.

Novel ecosystems: implications for conservation and restoration.

Many ecosystems are rapidly being transformed into new, non-historical configurations owing to a variety of local and global changes. We discuss how new systems can arise in the face of primarily biotic change (extinction and/or invasion), primarily abiotic change (e.g. land use or climate change) and a combination of both. Some changes will result in hybrid systems retaining some original characteristics as well as novel elements, whereas larger changes will result in novel systems, which comprise different species, interactions and functions. We suggest that these novel systems will require significant revision of conservation and restoration norms and practices away from the traditional place-based focus on existing or historical assemblages.