Methods for modeling fish responses to flow using time-series data

Although it is widely accepted that fishes are adapted to certain flow regimes, there have been few tests of hypotheses of which specific aspects of the flow regime induce responses to species with different traits. Seth Wenger, Ed Stowe, and Mary Freeman (USGS) are developing new approaches for using time-series data to test such hypotheses using long-term abundance data for fishes. This is part of a larger project led by Freeman, Wenger, Keith Gido (Kansas State), and Annika Walters (USGS) to advance flow ecology by testing mechanistic hypotheses. The work is funded by a grant from the Army Corps of Engineers to the USGS Powell Center, which hosted a working group meeting in spring 2019.

Monitoring fish and mussel populations in the Holly Creek watershed

This project is a collaboration with the Georgia Department of Natural Resources to survey fish and mussel populations in in the upper Holly Creek Watershed of the Conasauga Basin. The annual surveys will be used to guide restoration activities within the watershed and help inform how management actions in the watershed affect the aquatic community. In addition, the project contributes to our broader understanding of fish distributions within the Upper Coosa River. Funding is from the National Fish and Wildlife Foundation, which has identified Holly Creek as a high priority for restoration efforts. Phillip Bumpers leads this work in collaboration with Mary Freeman (USGS) and Ani Popp (GA DNR)

Long-term monitoring of shoal-dwelling fish communities in the Etowah and Conasauga Rivers

We have surveyed shoal-dwelling fish communities in the Conasauga and Etowah watersheds for about two decades to understand drivers and patterns of long-term fish population dynamics, particularly of threatened and endangered species. The resulting long-term datasets are central to our lab’s work to understand and predict fish distributions. Currently we are working to describe long-term fish abundance trends between the two rivers and assess species vulnerability to extinction, as well as understand how variation in river discharge and other climatic factors influence population and community dynamics in these rivers. We have also tested and developed e-DNA methods for rare species and are currently working on resolving genetic structure of a rare darter. Many students and technicians have contributed to this project over the years. Phillip Bumpers coordinates this work in collaboration with lead PI Bud Freeman (Director of the Georgia Museum of Natural History) and Mary Freeman (USGS). Funding comes from the Georgia Department of Natural Resources.

Multiple Population Viability Analysis

This recently-completed project developed new methods to estimate population viability for species that occur in multiple isolated populations. With funding from NASA, Bureau of Land Management, and other sources, Seth Wenger and postdoc Doug Leasure worked in collaboration with partners at Trout Unlimited, US Geological Survey, US Forest Service, and the University of Nevada Reno to develop new approaches that borrow information from well-studied populations to make inferences about populations with little or no data. The resulting methods are currently being used by US Fish and Wildlife Service, Nevada Department of Wildlife and other partners to support management of Lahontan Cutthroat Trout (Oncorhynchus clarkia henshawi), a threatened trout subspecies that mainly occurs in isolated mountain streams in the Great Basin. More details are in publications in the journals Biological Conservation, Ecology, and Conservation Biology.

Systematic conservation prioritization of the Upper Coosa River System

The Upper Coosa, composed of the Conasauga, Cooswattee, Etowah, and Oostanaula basins, is a highly biodiverse and imperiled river system. Recent protection and restoration of Raccoon Creek (Etowah Basin) by Paulding County, state agencies, federal agencies, and non-governmental organizations has been hailed as a conservation success story. Where could conservation go next? We are using spatial conservation prioritization to identify geographic areas that maximize conservation benefits and minimize costs. Outcomes of this work will help bridge the gap between conservation science and conservation action in a river system valued for its biodiversity. This work is led by Jon Skaggs. 

Population and ecosystem ecology of freshwater crabs in neotropical headwater streams

Monteverde, Costa Rica, is a region known for its cloud forests and high biodiversity. Headwater streams are an important part of the Monteverde cloud forest ecosystem and provide water resources for local and downstream human communities. Freshwater crabs are the largest macroconsumers in these streams, but very little is known about crab populations and factors that may affect their distribution across streams. We estimated crab densities using a mark-recapture method and found that stream sites in forested watersheds had more crabs than sites near human development. To estimate the role of crabs in the critical ecosystem process of leaf litter breakdown, we used an in-stream enclosure experiment combined with a laboratory feeding trial. Our results suggest that crabs can play a significant role in leaf breakdown and nutrient cycling in neotropical streams. This project is led by Carol Yang. 

Ecological function in the Middle Oconee River 

This project, led by Caitlin Conn, is described on the RBC website here

Stream fish habitat usage within restored streams

Stream restoration is a common tool used by natural resource managers to address aquatic impairment. In the US, it is increasingly employed to mitigate for unavoidable loss of stream habitat (e.g., when streams are piped during urban development). In recent decades, hundreds of stream restoration projects have been conducted just in in Georgia through Clean Water Act Section 404 mitigation banking program. Typically, these projects involve creation of structures such as rock vanes and artificial riffles within streams, but there is little evidence that these created habitats support diverse and abundant populations of native fishes. In this collaborative project, funded by USFWS and carried out by scientists from the USGS and UGA, we are quantifying fish diversity and density within restored and unrestored stream reaches. This project is led by Ed Stowe and conducted in collaboration with Mary Freeman (USGS). 

Using real-time sensors to monitor water quality

Urbanization is a primary source of impairment to water resources nationally. Urban areas create a particularly challenging environment to monitor and improve water quality because of the myriad sources of impairment and pollution. Real-time monitoring is being increasingly implemented world-wide to expand the temporal resolution of data and reduce costs associated with traditional time-intensive grab sample methods. We have built and are testing the efficacy of do-it-yourself real-time sensor stations for water quality monitoring in collaboration with the Athens-Clarke County government, with a focus on electrical conductivity as an early-warning indicator of impairment. Emily Johnson and Phillip Bumpers lead the work. Collaborators include John Dowd (emeritus, UGA Geography) and Amy Rosemond (OSE).

Predicting temperature across the southern Appalachians

This project involves the installation of a network of water temperature loggers and the development of a model to predict stream water temperature in un-monitored streams in the Little Tennessee River Watershed in North Carolina. The work includes a partnership with Trout Unlimited and Mainspring Conservation Trust to have citizen scientist volunteers “take the temperature” of local streams by adopting sites to deploy and periodically download temperature loggers. The development of a temperature model will also allow us to make predictions about future distributions of important taxa like Brook Trout, the only native salmonid the Southeastern US. In addition, the model will allow us predict the effect of climate warming on ecosystem processes across the watershed. This project is one component of a broader project that is studying the effects of climate warming on carbon processing and invertebrate communities in detritus-based streams. Phillip Bumpers coordinates the work in collaboration with Amy Rosemond (OSE), Jon Benstead (University of Alabama) and partners at  Mainspring Conservation Trust and Trout Unlimited.

Improving imperiled species protection and streamlining review of GDOT stream crossing projects

This project, coordinated by Jace Nelson, is funded by the Georgia Department of Transportation and involves collaborators from the Odum School, the Warnell School, the College of Engineering, the College of Environment and Design and the Georgia Museum of Natural History. See here for more information.

Natural history and ecology of the nine-banded armadillo on Georgia’s barrier islands

Our primary objective is to understand the role of the nine-banded armadillo (Dasypus novemcinctus) as an ecosystem engineer and invasive predator on Georgia’s barrier islands. More specifically, we are documenting the occurrence and behavior of commensal biodiversity in armadillo burrows. To date, no studies have quantified the extent to which commensal species rely on armadillo burrows and the potential benefits armadillos may provide as ecosystem engineers. Using ten years of sea turtle nest data from 12 barrier islands, we are also comparing the impact of sea turtle nest depredation by armadillos to native nest predators. This work will contribute to our understanding of barrier island and invasion ecology and aid division-making regarding armadillo and biodiversity management on Georgia’s barrier islands.