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Indirect estimates of gene flow and conservation implications in the striped newt (Notophthalmus perstriatus)
Title
Indirect estimates of gene flow and conservation implications in the striped newt (Notophthalmus perstriatus).
Creator
May, Sarah, Hoffman, Eric, Parkinson, Christopher, Johnson, Steve, University of Central Florida
Abstract / Description
This study used indirect methods to estimate patterns of gene flow in a rare salamander species, the striped newt (Notophthalmus perstriatus). First, we used combined genetic and ecological methods to determine whether populations that appear to exist in two regions separated by 125 km, exhibited genetic and ecological distinctness such that the regions demarcate separate conservation units. Using mtDNA (cyt-b), we found that haplotypes were shared between localities within each region but...
Show moreThis study used indirect methods to estimate patterns of gene flow in a rare salamander species, the striped newt (Notophthalmus perstriatus). First, we used combined genetic and ecological methods to determine whether populations that appear to exist in two regions separated by 125 km, exhibited genetic and ecological distinctness such that the regions demarcate separate conservation units. Using mtDNA (cyt-b), we found that haplotypes were shared between localities within each region but none were shared between regions. Niche-based distribution modeling revealed significant differences in the ecological setting between the two regions. In combination, the absence of evidence for recent genetic exchange and model-based support for differing ecological conditions utilized by newts between regions provides evidence that eastern and western populations are both distinct and significant. This study suggests a framework to evaluate discreteness and significance among populations for assessment of distinct population segments (DPSs which can be used as a conservation tool for many species. Second, we used microsatellites to characterize patterns of population connectivity, genetic differentiation, and effective population size in N. perstriatus. We assessed these patterns by testing several a priori hypotheses regarding the influence of gene flow and genetic drift on the distribution of genetic variation among and within populations. Interestingly, several of our results did not conform to our hypotheses. For example, our assessment did not reveal a significant pattern of isolation by distance among populations in this study. Additionally, we found that effective population sizes and genetic diversity of isolated populations were higher than expected. We discuss our results relate to our a priori hypotheses and we address the general question of why this species exhibited patterns contrary to what we expected given previous data on this taxon and other studies of similar taxa
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Date Issued
2011
Identifier
CFE0004481, ucf:49311
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0004481
The behavior of humans and wildlife with respect to roads: insights for mitigation and management
Title
The behavior of humans and wildlife with respect to roads: insights for mitigation and management.
Creator
Grace, Molly, Noss, Reed, Weishampel, John, Hoffman, Eric, Johnson, Steve, University of Central Florida
Abstract / Description
Road ecology is the study of how roads and wildlife interact. Traditionally, road ecologists have primarily focused on one effect of roads: roadkill. Though roadkill can have devastating effects on wildlife populations, roads have sub-lethal impacts that are gaining more and more attention from the scientific community. These sub-lethal impacts include noise, light, and chemical pollution as well as altered habitat structure, which can all influence animal behavior. In this dissertation, I...
Show moreRoad ecology is the study of how roads and wildlife interact. Traditionally, road ecologists have primarily focused on one effect of roads: roadkill. Though roadkill can have devastating effects on wildlife populations, roads have sub-lethal impacts that are gaining more and more attention from the scientific community. These sub-lethal impacts include noise, light, and chemical pollution as well as altered habitat structure, which can all influence animal behavior. In this dissertation, I applied a behavioral ecology framework to study specific lethal and sub-lethal road effects with the goal of improving mitigation efforts. In Chapters 1 and 2, I evaluated how human behavior may be modified to reduce wildlife-vehicle collisions; traditionally efforts have been made to modify wildlife road crossing behavior. I found that Roadside Animal Detection Systems, which warn drivers when animals are near the road, are successful in reducing crash risk; however, care must be taken to ensure that drivers do not become acclimated to the warning system. In Chapters 3 and 4, I evaluated how traffic noise affects subadult growth and adult abundance and communication of anuran amphibians (frogs and toads), a taxon widely recognized as one of the most negatively impacted by roads. I found that through traffic noise alters tadpole behavior, it does not appear to have a negative effect on their growth. Traffic noise does, however, negatively affect adult anuran abundance. My results indicate that this reduction in abundance is caused by the interference of traffic noise with anuran communication.
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Date Issued
2017
Identifier
CFE0006595, ucf:51275
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0006595