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This study seeks to understand the extent to which ecological connectivity has been considered in EIA in Canada. Several factors that may influence the consideration of connectivity were analyzed in an evaluation of 14 environmental impact statements (EIS) obtained from the Canadian Impact Assessment Registry. Connectivity is largely absent from the EIA process, and even projects that attempted to consider connectivity lacked the rigor required to effectively assess impacts on connectivity. Projects that included connectivity as a valued component performed somewhat better, whereas the assessment of connectivity was not affected by different federal environmental acts (CEAA 1992 vs. CEAA 2012), development sectors, or proponent types. Between sections of the EIS, a significantly greater number of evaluation criteria were met in the scoping section compared to all other sections. Without adequate guidance, connectivity analysis in EIA has been conducted ad hoc, with considerable variation in quality. Including connectivity consideration in EIA legislation would provide a legal framework to address the lack of policies, standards, and assessment guidelines. We provide recommendations for integrating connectivity in EIA in Canada and elsewhere. [ABSTRACT FROM AUTHOR]

Ecological connectivity should be an important consideration in environmental assessment (EA). How often and how thoroughly the analysis of ecological connectivity is integrated in the EA process is, however, unknown. We surveyed EA actors and stakeholders regarding their perceptions of, and experiences with, connectivity analysis in the context of EA. 134 practitioners, regulators, consultants, researchers, and interest groups from all inhabited continents participated. Over 72% of respondents stated that ecological connectivity should always be considered; however, it is often considered too late in the EA process, at a scale of analysis often unsuitable for capturing landscape-scale effects, and relying on overly simplistic metrics or qualitative approaches. This disparity between the availability of a range of quantitative tools and the poor consideration of connectivity in EA raises major concerns about current practice and the feasibility of connectivity analysis in project-based EA. Connectivity consideration will need to be required explicitly and supported by best-practice guidance to address the conditions that should trigger a connectivity analysis, the required types of approaches, and the kind of information required to inform decision-making. [ABSTRACT FROM AUTHOR]

Abstract In a review of landscape-scale empirical studies, Fahrig (2017a) found that ecological responses to habitat fragmentation per se (fragmentation independent of habitat amount) were usually non-significant (>70% of responses) and that 76% of significant relationships were positive, with species abundance, occurrence, richness, and other response variables increasing with habitat fragmentation per se. Fahrig concluded that to date there is no empirical evidence supporting the widespread assumption that a group of small habitat patches generally has lower ecological value than large patches of the same total area. Fletcher et al. (2018) dispute this conclusion, arguing that the literature to date indicates generally negative ecological effects of habitat fragmentation per se. They base their argument largely on extrapolation from patch-scale patterns and mechanisms (effects of patch size and isolation, and edge effects) to landscape-scale effects of habitat fragmentation. We argue that such extrapolation is unreliable because: (1) it ignores other mechanisms, especially those acting at landscape scales (e.g., increased habitat diversity, spreading of risk, landscape complementation) that can counteract effects of the documented patch-scale mechanisms; and (2) extrapolation of a small-scale mechanism to a large-scale pattern is not evidence of that pattern but, rather a prediction that must be tested at the larger scale. Such tests were the subject of Fahrig's review. We find no support for Fletcher et al.'s claim that biases in Fahrig's review would alter its conclusions. We encourage further landscape-scale empirical studies of effects of habitat fragmentation per se, and research aimed at uncovering the mechanisms that underlie positive fragmentation effects. Highlights • Habitat fragmentation per se is a landscape-scale phenomenon. • Cross-scale extrapolation from edge effects to fragmentation effects is unreliable. • Most responses to habitat fragmentation per se are non-significant. • Most significant responses to habitat fragmentation per se are positive. • Sets of small habitat patches with a large total area have high conservation value. [ABSTRACT FROM AUTHOR]