The Experts below are selected from a list of 5847 Experts worldwide ranked by ideXlab platform
Joseph E Hightower - One of the best experts on this subject based on the ideXlab platform.
-
multibeam sonar didson assessment of american shad alosa sapidissima approaching a hydroelectric Dam
Canadian Journal of Fisheries and Aquatic Sciences, 2014Co-Authors: Ann B Grote, Michael M Bailey, Joseph D Zydlewski, Joseph E HightowerAbstract:We investigated the fish community approaching the Veazie Dam on the Penobscot River, Maine, prior to implementation of a major Dam Removal and river restoration project. Multibeam sonar (dual-frequency identification sonar, DIDSON) surveys were conducted continuously at the fishway entrance from May to July in 2011. A 5% subsample of DIDSON data contained 43 793 fish targets, the majority of which were of Excellent (15.7%) or Good (73.01%) observation quality. Excellent quality DIDSON targets (n = 6876) were apportioned by species using a Bayesian mixture model based on four known fork length distributions (river herring (alewife, Alosa psuedoharengus, and blueback herring, Alosa aestivalis), American shad, Alosa sapidissima) and two size classes (one sea-winter and multi-sea-winter) of Atlantic salmon (Salmo salar). 76.2% of targets were assigned to the American shad distribution; Atlantic salmon accounted for 15.64%, and river herring 8.16% of observed targets. Shad-sized (99.0%) and salmon-sized (99.3...
-
multibeam sonar didson assessment of american shad alosa sapidissima approaching a hydroelectric Dam
Canadian Journal of Fisheries and Aquatic Sciences, 2014Co-Authors: Ann B Grote, Michael M Bailey, Joseph D Zydlewski, Joseph E HightowerAbstract:We investigated the fish community approaching the Veazie Dam on the Penobscot River, Maine, prior to implementation of a major Dam Removal and river restoration project. Multibeam sonar (dual-freq...
Michael M Bailey - One of the best experts on this subject based on the ideXlab platform.
-
multibeam sonar didson assessment of american shad alosa sapidissima approaching a hydroelectric Dam
Canadian Journal of Fisheries and Aquatic Sciences, 2014Co-Authors: Ann B Grote, Michael M Bailey, Joseph D Zydlewski, Joseph E HightowerAbstract:We investigated the fish community approaching the Veazie Dam on the Penobscot River, Maine, prior to implementation of a major Dam Removal and river restoration project. Multibeam sonar (dual-frequency identification sonar, DIDSON) surveys were conducted continuously at the fishway entrance from May to July in 2011. A 5% subsample of DIDSON data contained 43 793 fish targets, the majority of which were of Excellent (15.7%) or Good (73.01%) observation quality. Excellent quality DIDSON targets (n = 6876) were apportioned by species using a Bayesian mixture model based on four known fork length distributions (river herring (alewife, Alosa psuedoharengus, and blueback herring, Alosa aestivalis), American shad, Alosa sapidissima) and two size classes (one sea-winter and multi-sea-winter) of Atlantic salmon (Salmo salar). 76.2% of targets were assigned to the American shad distribution; Atlantic salmon accounted for 15.64%, and river herring 8.16% of observed targets. Shad-sized (99.0%) and salmon-sized (99.3...
-
multibeam sonar didson assessment of american shad alosa sapidissima approaching a hydroelectric Dam
Canadian Journal of Fisheries and Aquatic Sciences, 2014Co-Authors: Ann B Grote, Michael M Bailey, Joseph D Zydlewski, Joseph E HightowerAbstract:We investigated the fish community approaching the Veazie Dam on the Penobscot River, Maine, prior to implementation of a major Dam Removal and river restoration project. Multibeam sonar (dual-freq...
Jeffrey J Duda - One of the best experts on this subject based on the ideXlab platform.
-
shifting food web structure during Dam Removal disturbance and recovery during a major restoration action
PLOS ONE, 2020Co-Authors: Sarah A Morley, Jeffrey J Duda, Melissa M Foley, Mathew M Beirne, Rebecca Paradis, Rachelle Carina Johnson, Michael L Mchenry, Mel Elofson, Earnest M Sampson, Randall E MccoyAbstract:We measured food availability and diet composition of juvenile salmonids over multiple years and seasons before and during the world’s largest Dam Removal on the Elwha River, Washington State. We conducted these measurements over three sediment-impacted sections (the estuary and two sections of the river downstream of each Dam) and compared these to data collected from mainstem tributaries not directly affected by the massive amount of sediment released from the reservoirs. We found that sediment impacts from Dam Removal significantly reduced invertebrate prey availability, but juvenile salmon adjusted their foraging so that the amount of energy in diets was similar before and during Dam Removal. This general pattern was seen in both river and estuary habitats, although the mechanisms driving the change and the response differed between habitats. In the estuary, the dietary shifts were related to changes in invertebrate assemblages following a hydrological transition from brackish to freshwater caused by sediment deposition at the river’s mouth. The loss of brackish invertebrate species caused fish to increase piscivory and rely on new prey sources such as plankton. In the river, energy provided to fish by Ephemeroptera, Plecoptera, and Trichoptera taxa before Dam Removal was replaced first by terrestrial invertebrates, and then by sediment-tolerant taxa such as Chironomidae. The results of our study are consistent with many others that have shown sharp declines in invertebrate density during Dam Removal. Our study further shows how those changes can move through the food web and affect fish diet composition, selectivity, and energy availability. As we move further along the Dam Removal response trajectory, we hypothesize that food web complexity will continue to increase as annual sediment load now approaches natural background levels, anadromous fish have recolonized the majority of the watershed between and above the former Dams, and revegetation and microhabitats continue to develop in the estuary.
-
Dam Removal Information Portal (DRIP)-A Map-Based Resource Linking Scientific Studies and Associated Geospatial Information about Dam Removals Dam Removal Information Portal (DRIP)-A Map-Based Resource Linking Scientific Studies and Associated Geospatial
2020Co-Authors: Jeffrey J Duda, Jonathan A Warrick, Daniel J Wieferich, Sky R Bristol, Ryan J Bellmore, Vivian B Hutchison, Katherine M Vittum, Laura Craig, Director Suzette M Kimball, J J DudaAbstract:For more information on the USGS-the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment-visit http://www.usgs.gov/ or call 1-888-ASK-USGS (1-888-275-8747). For an overview of USGS information products, including maps, imagery, and publications, visit http://www.store.usgs.gov. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this information product, for the most part, is in the public domain, it also may contain copyrighted materials as noted in the text. Permission to reproduce copyrighted items must be secured from the copyright owner. Suggested citation: Duda, J.J., Wieferich, D.J., Bristol, R.S., Bellmore, J.R., Hutchison, V.B., Vittum, K.M., Craig, Laura, and Warrick, J.A., 2016, Dam Removal Information Portal (DRIP) Abstract The Removal of Dams has recently increased over historical levels due to aging infrastructure, changing societal needs, and modern safety standards rendering some Dams obsolete. Where possibilities for river restoration, or improved safety, exceed the benefits of retaining a Dam, Removal is more often being considered as a viable option. Yet, as this is a relatively new development in the history of river management, science is just beginning to guide our understanding of the physical and ecological implications of Dam Removal. Ultimately, the "lessons learned" from previous scientific studies on the outcomes Dam Removal could inform future scientific understanding of ecosystem outcomes, as well as aid in decision-making by stakeholders. We created a database visualization tool, the Dam Removal Information Portal (DRIP), to display map-based, interactive information about the scientific studies associated with Dam Removals. Serving both as a bibliographic source as well as a link to other existing databases like the National Hydrography Dataset, the derived National Dam Removal Science Database serves as the foundation for a Web-based application that synthesizes the existing scientific studies associated with Dam Removals. Thus, using the DRIP application, users can explore information about completed Dam Removal projects (for example, their location, height, and date removed), as well as discover sources and details of associated of scientific studies. As such, DRIP is intended to be a dynamic collection of scientific information related to Dams that have been removed in the United States and elsewhere. This report describes the architecture and concepts of this "metaknowledge" database and the DRIP visualization tool
-
large scale Dam Removal on the elwha river washington usa river channel and floodplain geomorphic change
Geomorphology, 2015Co-Authors: Amy E East, George R Pess, Jennifer A Bountry, Christopher S Magirl, Andrew C Ritchie, Joshua B Logan, Timothy J Randle, Mark C Mastin, J T Minear, Jeffrey J DudaAbstract:Abstract A substantial increase in fluvial sediment supply relative to transport capacity causes complex, large-magnitude changes in river and floodplain morphology downstream. Although sedimentary and geomorphic responses to sediment pulses are a funDamental part of landscape evolution, few opportunities exist to quantify those processes over field scales. We investigated the downstream effects of sediment released during the largest Dam Removal in history, on the Elwha River, Washington, USA, by measuring changes in riverbed elevation and topography, bed sediment grain size, and channel planform as two Dams were removed in stages over two years. As 10.5 million t (7.1 million m3) of sediment was released from two former reservoirs, downstream dispersion of a sediment wave caused widespread bed aggradation of ~ 1 m (greater where pools filled), changed the river from pool–riffle to braided morphology, and decreased the slope of the lowermost river. The newly deposited sediment, which was finer than most of the pre-Dam-Removal bed, formed new bars (largely pebble, granule, and sand material), prompting aggradational channel avulsion that increased the channel braiding index by almost 50%. As a result of mainstem bed aggradation, floodplain channels received flow and accumulated new sediment even during low to moderate flow conditions. The river system showed a two- to tenfold greater geomorphic response to Dam Removal (in terms of bed elevation change magnitude) than it had to a 40-year flood event four years before Dam Removal. Two years after Dam Removal began, as the river had started to incise through deposits of the initial sediment wave, ~ 1.2 million t of new sediment (~ 10% of the amount released from the two reservoirs) was stored along 18 river km of the mainstem channel and 25 km of floodplain channels. The Elwha River thus was able to transport most of the released sediment to the river mouth. The geomorphic alterations and changing bed sediment grain size along the Elwha River have important ecological implications, affecting aquatic habitat structure, benthic fauna, salmonid fish spawning and rearing potential, and riparian vegetation. The response of the river to Dam Removal represents a unique opportunity to observe and quantify funDamental geomorphic processes associated with a massive sediment influx, and also provides important lessons for future river-restoration endeavors.
-
baseline studies in the elwha river ecosystem prior to Dam Removal introduction to the special issue
Northwest Science, 2008Co-Authors: Jeffrey J Duda, Jerry E Freilich, Edward G SchreinerAbstract:Abstract The planned Removal of two Dams that have been in place for over 95 years on the Elwha River provides a unique opportunity to study Dam Removal effects. Among the largest Dams ever considered for Removal, this project is compelling because 83% of the watershed lies undisturbed in Olympic National Park. Eighteen million cubic meters of sediment have accumulated in and will be released from the reservoirs, and there is potential for rehabilitating depressed Pacific salmon runs. Researchers from academia, non-profit organizations, federal and state governments, and the Lower Elwha Klallam Tribe are currently assessing baseline ecological conditions of the Elwha River as part of Dam Removal studies. We introduce Dam Removal topics, provide a brief history of the Dams, and summarize the ecology of the Elwha River basin as an introduction to a special issue devoted to research in the watershed.
Charlotte Ravot - One of the best experts on this subject based on the ideXlab platform.
-
large Dam Removal and early spontaneous riparian vegetation recruitment on alluvium in a former reservoir lessons learned from the pre Removal phase of the selune river project france
River Research and Applications, 2020Co-Authors: Charlotte Ravot, Marianne Laslier, Laurence Hubertmoy, Simon Dufour, Didier Le Coeur, Ivan BernezAbstract:The restoration of ecological continuity along the Selune River (Normandy, France) involves the Removal of two tall hydroelectric Dams (36 m removed in 2019 and 16 m in 2021), a project without precedent in Europe. During the pre‐Removal phase (2014–2018), we performed scientific monitoring of the vegetation that was colonizing alluvium in the former Dam reservoir (length: 19 km; surface area: 151 ha). Our study aimed to analyse if spontaneous vegetation could ecologically restore the riparian zone and help maintain fine sediment after Dam Removal. We used colonization indicators related to vegetation structure, taxonomic richness and diversity, and composition. These indicators were calculated at two spatial scales (local, at a single site, and broad, along the reservoir). The aim was to (a) characterize the spontaneously established species pool; (b) analyse longitudinal patterns in vegetation colonization; and (c) assess temporal changes in the species community. Our results show that diverse plant communities have developed. Slight differences in longitudinal and lateral patterns existed; they were linked with habitat heterogeneity and the reservoir's slow pace of draining. We observed fast spontaneous terrestrialization, which has resulted in cover stabilization, decreased diversity, and the development of herbaceous riverbank communities, with very few invasive species. This finding suggests stabilization potential is high and passive ecological restoration could occur, at least locally. Further analyses focusing on functional traits could help inform future management decisions regarding revegetation on reservoir alluvium.
Ann B Grote - One of the best experts on this subject based on the ideXlab platform.
-
multibeam sonar didson assessment of american shad alosa sapidissima approaching a hydroelectric Dam
Canadian Journal of Fisheries and Aquatic Sciences, 2014Co-Authors: Ann B Grote, Michael M Bailey, Joseph D Zydlewski, Joseph E HightowerAbstract:We investigated the fish community approaching the Veazie Dam on the Penobscot River, Maine, prior to implementation of a major Dam Removal and river restoration project. Multibeam sonar (dual-frequency identification sonar, DIDSON) surveys were conducted continuously at the fishway entrance from May to July in 2011. A 5% subsample of DIDSON data contained 43 793 fish targets, the majority of which were of Excellent (15.7%) or Good (73.01%) observation quality. Excellent quality DIDSON targets (n = 6876) were apportioned by species using a Bayesian mixture model based on four known fork length distributions (river herring (alewife, Alosa psuedoharengus, and blueback herring, Alosa aestivalis), American shad, Alosa sapidissima) and two size classes (one sea-winter and multi-sea-winter) of Atlantic salmon (Salmo salar). 76.2% of targets were assigned to the American shad distribution; Atlantic salmon accounted for 15.64%, and river herring 8.16% of observed targets. Shad-sized (99.0%) and salmon-sized (99.3...
-
multibeam sonar didson assessment of american shad alosa sapidissima approaching a hydroelectric Dam
Canadian Journal of Fisheries and Aquatic Sciences, 2014Co-Authors: Ann B Grote, Michael M Bailey, Joseph D Zydlewski, Joseph E HightowerAbstract:We investigated the fish community approaching the Veazie Dam on the Penobscot River, Maine, prior to implementation of a major Dam Removal and river restoration project. Multibeam sonar (dual-freq...
