Featured Publication Conservation Genetics
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Anthropogenic climate change is altering aquatic ecosystems worldwide, particularly small and shallow systems such as wetlands. As a result of these abiotic changes, the terrestrial and aquatic species that depend on such wetlands are also likely to experience significant shifts in range, phenology, and population structure, particularly in arid and semi-arid regions already limited in water quantity and quality. We are developing a framework to determine and manage landscape-level impacts of climate change on wetlands and wetland-dependent species in semi-arid areas of North America’s Great Basin. We begin by determining the scope of abiotic impacts from climate change using remote sensing and ground-level monitoring to create models of the relationships between water volume, water quality, weather, and climate. We will then measure landscape-level population genetic connectivity of the aquatic invertebrates that serve as key prey species to the millions of migratory waterbirds that depend on these wetlands. We can use projections of future climate conditions to model how wetland habitat quality and species connectivity will change in the coming decades by combining estimates of landscape connectivity for these species with a model of the climate drivers of wetland patch quality. This approach will serve as a general model for understanding population- and community-level climate impacts and provide a sound basis for conservation planning and adaptive management by wetland resource managers around the world. The model will be made user-friendly for specific wetland management as well as provide regional perspectives. This novel approach integrates expertise from three USGS divisions and addresses seven of the nine broad goals and 10 more specific goals of the USGS Strategic Science Plan for the U.S. Climate Change Science Program, and will be a contribution to BLM’s Assessment, Inventory, and Monitoring (AIM), USGS Sagebrush Biome coordinated research projects, USGS’s Great Basin Integrated Landscape Monitoring (GBILM) Program, USGS SageMap program, Healthy Lands Initiative, USFWS National Shorebird Plan, North American Waterfowl Management Plan, and Western Hemisphere Shorebird Reserve Network. Read the project summary Predicting and Managing Climate Change Impacts on Semi-Arid Land Wetlands, Migratory Birds, and Their Prey: An Integration of Remote Sensing, Molecular Genetics, Hydrology, and Environmental Modeling For more information, contact Susan M. Haig, Forest and Rangeland Ecosystem Science Center; Mark P. Miller, Forest and Rangeland Ecosystem Science Center, Travis Schmidt, Fort Collins Science Center; and John Matthews, World Wildlife Fund (WWF). |
Coastal freshwater forested wetlands are under increasing stress associated with sea-level rise and salinization along the Gulf and south Atlantic Coasts. For nearly two decades, forest ecologists at the USGS National Wetlands Research Center in Lafayette, Louisiana have studied the eco-physiological and morphological responses of genetically distinct tree populations from these areas to different salinity and flood regimes. The goal of this research is to identify “improved” genotypes that can in turn be used for large-scale coastal swamp forest restoration efforts on marginal sites. Research to date has targeted baldcypress (Taxodium distichum) because of its longer term survival on salt-impacted sites as well as its broad tolerance to flooding. Studies have revealed strong intraspecific variation in tolerance to low salinity levels (approaching 4 ppt) among seedlings propagated from different coastal populations. However, persistent exposure to higher salinities eventually results in mortality for all genotypes. Recent research has suggested that natural selection may favor broad in lieu of narrow tolerances in baldcypress, thereby precluding strong adaptation to specific flood regimes. The consequences of such a broadly adaptive strategy for the future of salt tolerance improvement are unknown, but will continue to be a focus of this research. For more information, contact Ken W. Krauss, National Wetlands Research Center. Publications:
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Scientists at the USGS Western Ecological Research Center and the University of California, Santa Barbara, are developing libraries of the mitochondrial cytochrome oxidase I (COI) gene from easy-to-identify trematode cercariae to help in the identification of more difficult trematode stages by extracting DNA, Polymerase Chain Reaction (PCR) amplification and comparison with sequences from the libraries. By surveying the trematode parasite population in resident horn snails, a hub for more than 20 trematode species, whose lifestyle requires multiple sequential hosts, the scientists strive to develop trematodes as indicators of ecosystem health in estuaries along the Pacific Coast. Read more about the parasite studies: For more information contact Kevin D. Lafferty, Western Ecological Research Center.
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Protected areas most often encompass rare habitats, or “typical” exemplars of ecoregions and geomorphic provinces. This approach focuses on current biodiversity, and typically ignores the evolutionary processes that control the gain and loss of biodiversity at other levels (e.g., genetic, ecological). In order to include evolutionary process in conservation planning efforts, its spatial components must first be identified and mapped. We have developed a GIS-based approach for explicitly mapping patterns of genetic divergence and diversity for multiple species (a “Multi-species Genetic Landscape”, or MGL). Using this approach, we analyzed 21 mitochondrial DNA datasets from vertebrate and invertebrate species in Southern California to identify areas with common phylogeographic breaks and high intralineage diversity. The result is an evolutionary framework for southern California within which genetic biodiversity can be analyzed in the context of historical processes, future evolutionary potential and current reserve design. More information can be viewed at Finding Evolutionary Hotspots in Southern California for Conservation Planning. For more information, contact Amy Vandergast, Western Ecological Research Center. |
U.S. Department of the Interior |
U.S. Geological Survey
A recent article from the National Wetlands Research Center examines how plant populations may adapt to environmental conditions over time by developing genetically based morphological or physiological characteristics. Using baldcypress (Taxodium distichum (L.) L.C. Rich) from the southeastern United States, findings suggest that adaptations of coastal baldcypress to broad (rather than narrow) environmental conditions may promote ecophysiological and growth enhancements under a range of global-change-induced stressors, perhaps reflecting a natural resilience to environmental change while precluding adaptations for specific flood regimes.
