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We tested the hypotheses that species with greater mobility and/or higher reproductive rates are less sensitive to habitat loss than species with lower mobility and/or reproductive rates by conducting a meta-analysis of wetland vertebrate responses to wetland habitat loss. We combined data from 90 studies conducted worldwide that quantified the relationship between wetland amount in a landscape and population abundance of at least one wetland species to determine if mobility (indexed as home range size and body length) and annual reproductive rate influence species responses to wetland loss. When analyzed across all taxa, animals with higher reproductive rates were less sensitive to wetland loss. Surprisingly, we did not find an effect of mobility on response to wetland loss. Overall, wetland mammals and birds were more sensitive to wetland loss than were reptiles and amphibians. Our results suggest that dispersal between habitat patches is less important than species’ reproductive rates for population persistence in fragmented landscapes. This implies that immigration and colonization rate is most strongly related to reproduction, which determines the total number of potential colonists.

Conservation management of wetland-dependent species generally focuses on preserving or increasing wetland habitat. However, the quality of the landscape matrix (the intervening non-wetland portion of the landscape) has been shown to be more important than wetland availability for some wetland-dependent species. We used meta-analysis to compare the effects of wetland amount (measured as the area of wetland habitat in a landscape) and matrix quality (measured as the area of forest cover in the same landscape) on the population abundance of wetland-dependent vertebrates. We combined data across 63 studies conducted in forested ecoregions worldwide and extracted 330 population responses for 155 species, at the spatial scale that best predicted the effects of wetland. amount and forest amount for each response. In addition, to ensure that our results were not biased by the scale selected, we assessed whether the relative effects of wetland and forest amount were scale dependent. We found that the amount of wetland in a landscape had a larger effect than the amount of forest on the abundance of mammals and birds whereas, surprisingly, for amphibians the amount of forest in a landscape was more important than the amount of wetland. For reptiles, both wetland amount and forest amount showed only weak,effects on abundance. These results were not scale dependent, i.e., they were consistent across spatial scales. Our results suggest that the population distribution of wetland-dependent amphibians is more strongly related to landscape matrix quality than to wetland availability in a landscape, likely due to their requirement for access to terrestrial resources. We conclude that conservation policies for wetland biodiversity that focus only on wetland habitat will be ineffective in conserving many of these species. In addition, population viability analyses based only on wetland amount may overestimate the capacity of a landscape to support populations of wetland-dependent species.

This thesis is formatted using the integrated thesis format, and therefore each data chapter was written as an independent manuscript. Chapters 2 and 3 have been published in, and Chapter 4 has been submitted to, a peer-reviewed journal when this thesis was completed. The text of each published chapter was reproduced in whole, but supplementary figures were added. There is some repetition in the introductions, methods and discussions; however I have cross-referenced between chapters to reduce repetition as much as possible. I performed the majority of work described in this thesis as follows. I proposed and developed the research questions in cooperation with Lenore Fahrig and Kathryn Lindsay, and I was primarily responsible for the design of the studies used to address these questions. I carried out all field work for Chapter 3 and collected all data for Chapters 2 and 4. I analysed all of the data and wrote all first drafts of the data chapters. I have permission from each publisher to reproduce published manuscripts in my thesis. I have also received permission from my co-authors Lenore Fahrig and Kathryn Lindsay to use the work in this thesis. A specific chapter that has been published elsewhere is copyrighted material and must be cited using the journal citation information provided below. However, to reference my thesis as a whole or an unpublished chapter, I recommend using the following citation: v Quesnelle, P.E. 2014. Relative effects of landscape structure variables, and interactions with life-history traits, on the abundance and distribution of wetland-dependent vertebrate species. Ph.D. Thesis,