Amanda Demopoulos, Ph.D.
I lead multidisciplinary investigations into coastal and deep-sea benthic communities funded by USGS-EMA and partners, including BOEM and NOAA, that pull together scientists and experts from across USGS, as well as NOAA, BOEM, and many academic institutions. Deep-sea investigations are complex and logistically challenging and require an interdisciplinary approach to disentangle what makes them tick.
Science and Products
Exploration of Caribbean Seamounts within the Greater and Lesser Antilles (GA/LA) Transition Zone: Characterization of the Benthic Ecology and Geology
Connectivity of Tropical Marine Ecosystems: Understanding Biodiversity and Trophic Relationships in the Virgin Islands and Puerto Rico
Stable isotope ratios of carbon and nitrogen from diamondback terrapins and resources within Southern Everglades and Key West National Wildlife Refuge, sampled 2012-2013
Data release for Food-web structure canyon- and slope-associated fauna revealed by stable isotopes
Macrobenthic infaunal communities associated with deep-sea hydrocarbon seeps in the Gulf of Mexico, 2009-2010
Host Feeding Ecology and Trophic Position Significantly influence Isotopic discrimination between a Generalist Ectoparasite and its hosts: Implications for parasite host trophic studies
Sediment macrofaunal composition, sediment grain size, and taxa functional traits of multiple deep-sea coral habitats in the Gulf of Mexico, 2009-2014
Baseline data for a hydrological restoration of a mangrove forest near Goodland, Florida (2015 - 2017)
Trophic structure of mesopelagic fishes in the Gulf of Mexico revealed by gut content and stable isotope analyses
Demersal fish assemblages on seamounts and other rugged features in the northeastern Caribbean
Food-web dynamics and isotopic niches in deep-sea communities residing in a submarine canyon and on the adjacent open slopes
A characterization of deep-sea coral and sponge communities along the California and Oregon coast using a remotely operated vehicle on the EXPRESS 2018 expedition
Potential for carbon and nitrogen sequestration by restoring tidal connectivity and enhancing soil surface elevations in denuded and degraded south Florida mangrove ecosystems
Introduced mangroves along the coast of Moloka‘i, Hawai‘i may represent novel habitats for megafaunal communities
New geochemical tools for investigating resource and energy functions at deep-sea cold seeps using amino-acid δ15N in chemosymbiotic mussels (Bathymodiolus childressi)
The role of habitat heterogeneity and canyon processes in structuring sediment macrofaunal communities associated with hard substrate habitats in Norfolk Canyon, USA
Biology characterization breakout report
Stable isotope dynamics of herbivorous reef fishes and their ectoparasites
Distribution of deep-water scleractinian and stylasterid corals across abiotic environmental gradients on three seamounts in the Anegada Passage
Cascadia Margin cold seeps: Subduction zone fluids, gas hydrates, and chemosynthetic habitats
Mapping, exploration, and characterization of the California continental margin and associated features from the California-Oregon border to Ensenada, Mexico
Submarine canyons influence macrofaunal diversity and density patterns in the deep-sea benthos
Benthic infaunal communities of Baltimore and Norfolk Canyons
Non-USGS Publications**
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
Science and Products
- Science
Filter Total Items: 14
Exploration of Caribbean Seamounts within the Greater and Lesser Antilles (GA/LA) Transition Zone: Characterization of the Benthic Ecology and Geology
Seamounts may be biodiversity hotspots, oases, islands, and centers for endemism in the deep sea. USGS and partners explore these possibilities within the Greater and Lesser Antilles Transition Zone.Connectivity of Tropical Marine Ecosystems: Understanding Biodiversity and Trophic Relationships in the Virgin Islands and Puerto Rico
Marine reserves and protected areas in the U.S. Virgin Islands and Puerto Rico encompass a variety of tropical ecosystems, including coral reefs, mangroves, and seagrass beds, but questions remain regarding how effective these areas are at preserving and protecting the habitats and species they encompass. USGS and collaborators address this question by examining the biodiversity and food web... - Data
Filter Total Items: 21
Stable isotope ratios of carbon and nitrogen from diamondback terrapins and resources within Southern Everglades and Key West National Wildlife Refuge, sampled 2012-2013
This study was initiated to provide baseline data and to determine the utility of stable isotope analysis to evaluate the foraging strategies of an opportunistic reptile predator. Stable isotope ratios of carbon and nitrogen were evaluated from multiple tissues from terrapin populations to determine spatial or temporal variations in resource use within mangrove habitats in Southern Florida. We samData release for Food-web structure canyon- and slope-associated fauna revealed by stable isotopes
The primary objective of this study was to assess deepsea food web structure and trophic niches in Baltimore and Norfolk canyons, the adjacent slopes, and chemosynthetic seeps along the mid-Atlantic margin using stable isotope analyses (SIA) and isotope niche width analysis. We hypothesized that the isotopic compositions of canyon versus slope fauna would be distinct, given differences in the physMacrobenthic infaunal communities associated with deep-sea hydrocarbon seeps in the Gulf of Mexico, 2009-2010
These data represent several benthic cores collected near chemosynthetic seep habitats during 2009 and 2012. Sediment cores were collected near several natural hydrocarbon seeps with ROV deployed push cores. The purpose of these samples is to examine benthic communities associated with natural hydrocarbon seepage in the deep sea as well as compare these communities to areas associated with the DeeHost Feeding Ecology and Trophic Position Significantly influence Isotopic discrimination between a Generalist Ectoparasite and its hosts: Implications for parasite host trophic studies
Despite being one of the most prevalent forms of consumerism in ecological communities, parasitism has largely been excluded from food-web models. Stable isotope analysis of consumers and their diets has been widely used in the study of food-webs for decades. However, the amount of information regarding parasite stable isotope ecology is limited, restricting the ability of ecologists to use stableSediment macrofaunal composition, sediment grain size, and taxa functional traits of multiple deep-sea coral habitats in the Gulf of Mexico, 2009-2014
Deep-sea corals can create a highly complex, three-dimensional structure that facilitates sediment accumulation and influences adjacent sediment environments through altered hydrodynamic regimes. Infaunal communities adjacent to different coral types, including reef-building scleractinian corals and individual colonies of octocorals, are known to differ from background non-coral soft-sediment commBaseline data for a hydrological restoration of a mangrove forest near Goodland, Florida (2015 - 2017)
Mangrove restoration has a strong potential to enhance the services provided by coastal wetlands on a number of Department of the Interior (DOI) managed lands throughout the southeastern United States of America. Services include storm protection, water quality improvement, and biological carbon sequestration. Forest structural attributes including basal area, tree height, and stem density by specTrophic structure of mesopelagic fishes in the Gulf of Mexico revealed by gut content and stable isotope analyses
Mesopelagic fishes represent an important component of the marine food web due to their global distributions, high abundances and ability to transport organic material throughout a large part of the water column. This study combined stable isotope (SIA) and gut content analyses (GCA) to characterize the trophic structure of mesopelagic fishes in the north central Gulf of Mexico. Additionally thisDemersal fish assemblages on seamounts and other rugged features in the northeastern Caribbean
Recent investigations of demersal fish communities in deep (less than 50 m) rugged habitats have considerably increased our knowledge of the factors that influence the assemblage structure of fishes across mesophotic to deep-sea depths. Although habitat types influence deepwater fish distribution, whether different rugged seafloor features provide functionally equivalent habitat for fishes is poorFood-web dynamics and isotopic niches in deep-sea communities residing in a submarine canyon and on the adjacent open slopes
Examination of food webs and trophic niches provide insight into organisms functional ecology, yet few studies have examined the trophodynamics within submarine canyons, where the interaction of morphology and oceanography influences food deposition. Stable isotope analysis and Bayesian ellipses documented deep-sea food web structure and trophic niches in Baltimore Canyon and the adjacent open slo - Maps
- Publications
Filter Total Items: 74
A characterization of deep-sea coral and sponge communities along the California and Oregon coast using a remotely operated vehicle on the EXPRESS 2018 expedition
Deep-sea coral and sponge (DSCS) communities serve as essential fish habitats (EFH) by providing shelter and nursery habitat, increasing diversity, and increasing prey availability (Freese and Wing, 2003; Bright, 2007; Baillon et al., 2012; Henderson et al., 2020). Threats to these long-lived, fragile organisms from bottom contact fishing gear, potential offshore renewable energy development, andAuthorsTom Laidig, Diana Watters, Nancy G. Prouty, Meredith Everett, Lizzie Duncan, Liz Clarke, Chris Caldow, Amanda DemopoulosPotential for carbon and nitrogen sequestration by restoring tidal connectivity and enhancing soil surface elevations in denuded and degraded south Florida mangrove ecosystems
Mangroves are tidally dependent wetlands that are influenced often by alterations in hydrology associated with coastal developments that impact their distribution, health, and function. Alteration in frequency, depth, duration, and seasonality of tidal inundation can lead to changes in forest condition, although these stress-adapted ecosystems may persist for many years before succumbing to mortalAuthorsN. Cormier, Ken Krauss, Amanda Demopoulos, Brita J. Jessen, Jennifer McClain Counts, Andrew From, Laura L. FlynnIntroduced mangroves along the coast of Moloka‘i, Hawai‘i may represent novel habitats for megafaunal communities
Mangrove forests are prevalent along tropical/subtropical coastlines and provide valuable ecosystem services including coastline stabilization, storm impact reduction, and enhanced coastal productivity. However, mangroves were absent from the Hawaiian Islands and their introduction to Moloka‘i in 1902 has provided an opportunity to examine their unique influence on coastal landscapes. Previous stuAuthorsBryan A. Nakahara, Amanda Demopoulos, Yoshimi M. Rii, Rosanna A. Alegado, Kauaoa M.S. Fraiola, Craig R. SmithNew geochemical tools for investigating resource and energy functions at deep-sea cold seeps using amino-acid δ15N in chemosymbiotic mussels (Bathymodiolus childressi)
In order to reconstruct the ecosystem structure of chemosynthetic environments in the fossil record, geochemical proxies must be developed. Here, we present a suite of novel compound-specific isotope parameters for tracing chemosynthetic production with a focus on understanding nitrogen dynamics in deep-sea cold seep environments. We examined the chemosymbiotic bivalve Bathymodiolus childressi froAuthorsNatasha Vokhshoori, Matt McCarthy, Hilary Close, Amanda Demopoulos, Nancy G. ProutyThe role of habitat heterogeneity and canyon processes in structuring sediment macrofaunal communities associated with hard substrate habitats in Norfolk Canyon, USA
Topographic and hydrodynamic complexity in submarine canyons promotes steep gradients in food availability and geophysical parameters which affect ecological assemblages and beta diversity. While habitat heterogeneity in submarine canyons is known to support diverse and abundant megafaunal communities, due to difficulty in sampling little is known about infaunal communities adjacent to hard substrAuthorsJill Bourque, Amanda Demopoulos, Craig M. Robertson, Furu MienisBiology characterization breakout report
The primary goal of the biology characterization breakout group was to identify the strategies, tools, data priorities, and key partnerships needed to conduct baseline biological characterizations of deep-sea benthic environments across the U.S. EEZ in the Pacific. Discussions focused primarily on priorities for the characterization of deep-water (>200-meter depths) benthic biological communities;AuthorsAmanda Demopoulos, Daniel Wagner, Amy Baco-Taylor, David Itano, Diva Amon, Erik E. Cordes, Lisa Levin, Peter H. Edwards, Randall Kosaki, Shirley Pomponi, Steve GittingsStable isotope dynamics of herbivorous reef fishes and their ectoparasites
Acanthurids (surgeonfishes) are an abundant and diverse group of herbivorous fishes on coral reefs. While their contribution to trophic linkages and dynamics in coral reef systems has received considerable attention, the role of linkages involving their parasites has not. As both consumers of fish tissue and prey to microcarnivores, external parasites may play a significant role in trophic transfeAuthorsWilliam Jenkins, Amanda Demopoulos, Matthew C. Nicholson, Paul C. SikkelDistribution of deep-water scleractinian and stylasterid corals across abiotic environmental gradients on three seamounts in the Anegada Passage
In the Caribbean Basin the distribution and diversity patterns of deep-sea scleractinian corals and stylasterid hydrocorals are poorly known compared to their shallow-water relatives. In this study, we examined species distribution and community assembly patterns of scleractinian and stylasterid corals on three high-profile seamounts within the Anegada Passage, a deep-water throughway linking theAuthorsSteven R. Auscavitch, Jay J. Lunden, Alexandria Barkman, Andrea Quattrini, Amanda Demopoulos, Erik E. CordesCascadia Margin cold seeps: Subduction zone fluids, gas hydrates, and chemosynthetic habitats
Priority Geographic Area: The outer continental shelf and upper continental slope from Canada/U.S. border offshore Washington State to the Mendocino Fracture Zone (Northern California), entirely within the U.S. Exclusive Economic Zone (EEZ), from the outermost shelf to at least 2000 m water depth (Figure 1). Description of Priority Area: Since 2015, over a thousand water column gas plumes originatAuthorsAmanda Demopoulos, Carolyn D. Ruppel, Nancy G. Prouty, Janet Watt, Tamara Baumberger, David A ButterfieldMapping, exploration, and characterization of the California continental margin and associated features from the California-Oregon border to Ensenada, Mexico
Priority Geographic Area: Both within and outside US Exclusive Economic Zone (EEZ). California continental margin. This area includes and continues south of the geographic area captured in the Watt et al. white paper. Description of Priority Area: The California continental margin, from the narrow shelf to abyssal depths, contains diverse seafloor features that influence benthic community types, bAuthorsAmanda Demopoulos, Nancy G. Prouty, Daniel S. Brothers, Janet Watt, James E. Conrad, Jason Chaytor, Chris CaldowSubmarine canyons influence macrofaunal diversity and density patterns in the deep-sea benthos
Submarine canyons are often morphologically complex features in the deep sea contributing to habitat heterogeneity. In addition, they act as major conduits of organic matter from the shallow productive shelf to the food deprived deep-sea, promoting gradients in food resources and areas of sediment resuspension and deposition. This study focuses on the Baltimore and Norfolk canyons, in the westernAuthorsCraig M. Robertson, Amanda Demopoulos, Jill Bourque, Furu Mienis, Gerard Duineveld, Mark Lavaleye, R. Koivisto, S. Brooke, S. Ross, M. Rhode, A. DaviesBenthic infaunal communities of Baltimore and Norfolk Canyons
The imperative for finding, cataloging, and understanding continental margin diversity derives from the many key functions, goods and services provided by margin ecosystems and by an increasingly deleterious human footprint on our continental slopes (Levin and Dayton 2009). Progress in seafloor mapping technology and direct observation has revealed unexpected heterogeneity, with a mosaic of habitaAuthorsCraig M. Robertson, Jill Bourque, Amanda DemopoulosNon-USGS Publications**
Demopoulos, A.W.J., B. Fry., C.R. Smith. 2007. Food-web structure in exotic and native mangroves: a Hawaii-Puerto Rico comparison, Oecologia. 153:675-686.Cordes EE, Berlet SP, Cardman Z, Dannenberg R, Demopoulos AWJ, Georgian SE, King C, McKean DL, Young DM. 2014. Exploring deep-sea coral communities and the effects of oil and gas inputs to the Gulf of Mexico. Oceanography 27(supplement): 28-29. doi:10.5670/oceanog.2014.supplement.01ten Brink, U., D.F. Coleman, J. Chaytor, A.W.J. Demopoulos, R. Armstrong, G. Garcia-Moliner, N.A. Raineault, B. Andrews, R. Chastain, K. Rodrigue, M. Mercier-Gingras. 2014. Earthquake, Landslide, and Tsunami Hazards and Benthic Biology in the Greater Antilles. Oceanography 27(supplement): 34-35. doi:10.5670/oceanog.2014.supplement.01Morrison, C.L., Baco, A.R., Nizinski, M.S., Coykendall, D.K., Demopoulos, A.W.J., Cho, W., Shank, T.M. 2014. Population connectivity of deep-sea corals. In: T.F. Hourigan, P. Etnoyer (Eds). The State of Deep Coral Ecosystems of the United States: NOAA Technical Memorandum. Silver Spring, MD. In Press.Demopoulos, A.W.J. and C.R. Smith. 2010. Invasive mangroves alter macrofaunal community structure and facilitate opportunistic exotics. Mar. Ecol. Prog. Ser. 404:51-67Fry, B., N. Cormier, and A.W.J. Demopoulos 2009. Adventures in an isotopically ordered world-the chemical ecology of Micronesian mangroves and crabs, Pages 50-56 in N. Yoshida, ed., Proceedings of the 4th International Conference on Isotopomers, ISI2008-18, 292 pp.Demopoulos, A.W.J. 2004. Black Mangrove Benthic Community Structure, Seedling Growth and Survival, and Sediment Characteristics in Anthropogenically Disturbed and Pristine Habitats, NOAA/NERR final report, Jobos Bay National Estuarine Research Reserve, Puerto Rico.Demopoulos, A.W.J. 2003. Introduced mangroves in the Hawaiian Islands: Their history and impact on Hawaiian coastal ecosystems. In: Global Invasive Species Programme-Invasive Species Report following the conference on the Ecological and Socio-Economic Impacts of Invasive Alien Species on Island Ecosystems.Demopoulos, A.W.J. 2004. Aliens in paradise: a comparative assessment of introduced and native mangrove benthic community composition, food-web structure, and litter-fall production. Ph.D. Thesis. Dept. of Oceanography, University of Hawaii.Smith, C.R. and A.W.J. Demopoulos. 2003. Ecology of the deep Pacific Ocean floor. In: Ecosystems of the World Volume 28: Ecosystems of the Deep Ocean, P.A. Tyler, ed., Elsevier, Amsterdam, 569 pp.Demopoulos, A.W.J., C.R. Smith, and P.A. Tyler. 2003. Ecology of the deep Indian Ocean floor. In: Ecosystems of the World Volume 28: Ecosystems of the Deep Ocean, P.A. Tyler, ed., Elsevier, Amsterdam. 569 pp.Demopoulos, A.W.J., C.R. Smith, D.J. DeMaster and W. Fornes. 2003. Evaluation of excess 234Th activity in sediments as an indicator of food quality for deep-sea deposit feeders. J. Mar. Res. 61:267-284.Demopoulos, A.W.J. 2000. Evaluation of excess 234Th activity in sediments as an indicator of food quality for deep-sea deposit feeders, M.S. Thesis. Dept. of Oceanography, University of Hawaii.Levin, L.A., fT.S. Talley, A.A. Larson, A. Jones*. 1997. Faunal composition in the Tijuana River Estuary Intertidal Habitats and the role of life histories in the faunal recovery of Southern California Restored Wetlands. Final Report to the Tijuana River National Estuarine Research Reserve. NOAA Award, No. NA 670R0237. NOAA.Levin, L., D. Talley, T. Talley, A. Larson, A. Jones*, G. Thayer, C. Currin, and C. Lund. 1997. Restoration of Spartina marsh function: An infaunal perspective. Conference Proceedings, Society for Ecological Restoration, 1995 International Conference. Seattle, Washington. Sept. 14-16, 1995.**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
- News
Filter Total Items: 14