Physical Sciences and Mathematics Commons^™

Evaluating Benthic Macroinvertebrate Populations In Response To Scouring Events In The Trinity River, Ca, Liam Hay, Michael W. O'Neil, Chloe Pieper-Wasem

Environmental Science & Management Senior Capstones

River systems across California have been impacted by appurtenant structures such as dams and diversions. These structures have had an adverse impact on Benthic invertebrate (BMI) communities by regulating river systems and changing the natural hydraulic pulses that follow seasonal precipitation. Benthic invertebrates are a critical food resource for salmonids and serve as an indicator of ecosystem health. Our study was interested in seeing the effects of scouring events on BMI in the Trinity River of Trinity County, C.A. Following a large precipitation event that occurred in the region in December 2022, an influx of water entered the river through …

Southern California Margin Benthic Foraminiferal Assemblages Record Recent Centennial-Scale Changes In Oxygen Minimum Zone, Hannah M. Palmer, Tessa M. Hill, Peter D. Roopnarine, Sarah E. Myhre, Kastherine R. Reyes, Jonas T. Donnenfield

Natural Sciences and Mathematics | Student Professional Publications

Microfossil assemblages provide valuable records to investigate variability in continental margin biogeochemical cycles, including dynamics of the oxygen minimum zone (OMZ). Analyses of modern assemblages across environmental gradients are necessary to understand relationships between assemblage characteristics and environmental factors. Five cores were analyzed from the San Diego margin (32∘42′00′′ N, 117∘30′00′′ W; 300–1175 m water depth) for core top benthic foraminiferal assemblages to understand relationships between community assemblages and spatial hydrographic gradients as well as for down-core benthic foraminiferal assemblages to identify changes in the OMZ through time. Comparisons of benthic foraminiferal assemblages from two size fractions (63–150 and >150 …

Fishes Of The Northern Mid-Atlantic Ridge Collected During The Mar-Eco Cruise In June-July 2004: An Annotated Checklist, Filipe M. Porteiro, Tracey Sutton, Ingvar Byrkjedal, Alexy M. Orlov, Mikko Heino, Gui Menezes, Odd Aksel Bergstad

Marine & Environmental Sciences Faculty Reports

Records of the fishes from the northern Mid-Atlantic Ridge (MAR) (41⁰N - 60⁰N) sampled during two research cruises conducted in summer 2004 on the R/V G.O. Sars and M/S Loran are presented. The cruises were major sampling efforts carried out for the MAR-ECO project, i.e. the Census of Marine Life field project entitled “Patterns and Processes of the Ecosystems of the Northern Mid-Atlantic”. The investigation included sampling with several midwater nets, bottom trawl and longlines from surface waters to about 4000 m. The list comprises around 300 species of fishes from 82 families. Many records were new to the northern …

Macroinvertebrate Assemblages And Dynamic Soil Properties: Influence Of Dredging, Bianca N. Ross

Senior Honors Projects

Bianca Peixoto

Senior Honors Project

Macroinvertebrate Assemblages and Dynamic Soil Properties: Influence of Dredging: Abstract

The habitat characterization of subaqueous soils is important for inventorying natural resources and monitoring changes in ecosystem processes. This project aimed to characterize benthic communities within coastal ponds of southern Rhode Island, and develop an understanding of how these communities change due to habitat alterations. I explored the distribution of benthic biology among a range of estuarine subaqueous soils and the effect of anthropogenic disturbance (dredging) on these distributions. The term “benthic” refers to the collection of organisms living in the substrate at the interface …

Benthic And Planktonic Microalgal Community Structure And Primary Productivity In Lower Chesapeake Bay, Matthew Reginald Semcheski

Biological Sciences Theses & Dissertations

Microalgal populations are trophically important to a variety of micro- and macroheterotrophs in marine and estuarine systems. In Chesapeake Bay, microalgae facilitate the survival and development of ecologically and economically relevant fauna, including shellfish and finfish populations. While regarded as significant components of coastal environments, microphytobenthic communities are historically understudied. In Chesapeake Bay, the importance of phytoplankton to the ecosystem is understood, but the contribution of microphytobenthos remains unclear. This project surveys intertidal microphytobenthic communities, in relation to phytoplankton communities, around lower Chesapeake Bay describing the taxonomic makeup of these populations, coupled with quantification of cell abundance, biomass, and primary …

Nearshore Benthic Oxygen Dynamics In Lake Michigan, Emily H. Tyner

Theses and Dissertations

The intense colonization of the Laurentian Great Lakes by dreissenid mussels has profoundly changed ecosystem processes, particularly benthic oxygen dynamics. Dissolved oxygen concentrations in mussel beds, sloughed Cladophora mats, and sediment indicate that hypoxia forms and disappears in some substrata (ephemeral Cladophora mats), while occurring consistently in others (depositional areas of sloughed Cladophora). Dissolved organic carbon concentrations are high (mean: 143 ± ± 28 ppm) in depositional Cladophora mats but lower (˂ 10 ppm) in most other environments. Field sampling and laboratory experiments suggest that under conditions of low water velocity and thick Cladophora cover, hypoxia may develop atop …

Light And Vision In The Deep-Sea Benthos: I. Bioluminescence At 500-1000 M Depth In The Bahamian Islands, Sönke Johnsen, Tamara M. Frank, Steven H.D. Haddock, Edith A. Widder, Charles G. Messing

Marine & Environmental Sciences Faculty Articles

Bioluminescence is common and well studied in mesopelagic species. However, the extent of bioluminescence in benthic sites of similar depths is far less studied, although the relatively large eyes of benthic fish, crustaceans and cephalopods at bathyal depths suggest the presence of significant biogenic light. Using the Johnson-Sea-Link submersible, we collected numerous species of cnidarians, echinoderms, crustaceans, cephalopods and sponges, as well as one annelid from three sites in the northern Bahamas (500–1000 m depth). Using mechanical and chemical stimulation, we tested the collected species for light emission, and photographed and measured the spectra of the emitted light. In addition, …

Light And Vision In The Deep-Sea Benthos: Ii. Vision In Deep-Sea Crustaceans, Tamara M. Frank, Sönke Johnsen, Thomas W. Cronin

Marine & Environmental Sciences Faculty Articles

Using new collecting techniques with the Johnson-Sea-Link submersible, eight species of deep-sea benthic crustaceans were collected with intact visual systems. Their spectral sensitivities and temporal resolutions were determined shipboard using electroretinography. Useable spectral sensitivity data were obtained from seven species, and in the dark-adapted eyes, the spectral sensitivity peaks were in the blue region of the visible spectrum, ranging from 470 to 497 nm. Under blue chromatic adaptation, a secondary sensitivity peak in the UV portion of the spectrum appeared for two species of anomuran crabs:Eumunida picta (λ_max 363 nm) and Gastroptychus spinifer (λ_max 383 nm). Wavelength-specific …

Spatial Modelling Of Benthic Cover Using Remote Sensing Data In The Aldabra Lagoon, Western Indian Ocean, Sarah Hamylton, Tom Spencer, A Hagan

Faculty of Science - Papers (Archive)

Spatially explicit ecological modelling was used to predict the distribution of 4 benthic components (live coral, carbonate sand, macroalgae and dead coral) inside the Aldabra lagoon, southern Seychelles, western Indian Ocean. Both classic ordinary least-squares and spatial autoregression techniques were carried out on a field data set of 774 spatially referenced records and 3 satellite remote sensing images to define an empirical relationship between local environmental conditions (water depth and water level variation) and benthic cover. This relationship was then used to generate a synoptic model of the spatial cover and distribution of each benthic component at the landscape (i.e. …

Oxidation Of Acid-Volatile Sulfide In Surface Sediments Increases The Release And Toxicity Of Copper To The Benthic Amphipod Melita Plumulosa, Stuart L. Simpson, Daniel Ward, David Strom, Dianne F. Jolley

Faculty of Science - Papers (Archive)

Acid-volatile sulfides (AVS) are an important metal-binding phase in sediments. For sediments that contain an excess of AVS over simultaneously extracted metal (SEM) concentrations, acute or chronic effects should not result from the metals Cd, Cu, Ni, Pb and Zn. While AVS phases may exist in surface sediments, the exposure to dissolved oxygen may oxidize the AVS and release metals to more bioavailable forms. We investigated the role of oxidation of AVS, and specifically copper sulfide phases, in surface sediments, in the toxicity to juveniles of the epibenthic amphipod, Melita plumulosa. Sediments containing known amounts of copper sulfide were prepared …

Rumbling In The Benthos: Acoustic Ecology Of The California Mantis Shrimp Hemisquilla Californiensis, E. Staaterman, C. Clark, A. Gallagher, M. Devries, T. Claverie, S. Patek

Faculty Publications, Biological Sciences

Although much research has focused on acoustic mapping and exploration of the benthic environment, little is known about the acoustic ecology of benthic organisms, particularly benthic crustaceans. Through the use of a coupled audio–video system, a hydrophone array, and an autonomous recording unit, we tested several hypotheses about the field acoustics of a benthic marine crustacean, Hemisquilla califor­niensis. Living in muddy burrows in southern California, these large mantis shrimp produce low frequency ‘rumbles’ through muscle vibrations. First, we tested whether acoustic signals are similar in the field and in the laboratory, and discovered that field-produced rumbles are more acoustically and …

Mercury In The Pelagic And Benthic Food Webs Of The Great Salt Lake, Wayne A. Wurtsbaugh, Erin Fleming, Caleb Izdepski, Jodi Gardberg

Watershed Sciences Faculty Publications

No abstract provided.

The Influence Of Sediment Particle Size And Organic Carbon On Toxicity Of Copper To Benthic Invertebrates In Oxic/Suboxic Surface Sediments, David Strom, Stuart L. Simpson, Graeme E. Batley, Dianne F. Jolley

Faculty of Science - Papers (Archive)

The use of sediment quality guidelines to predict the toxicity of metals in sediments is limited by an inadequate understanding of exposure pathways and by poor causal links between exposure and effects. For a 10-d exposure to Cu-spiked sediments, toxicity to the amphipod Melita plumulosa was demonstrated to occur through a combination of dissolved and dietary Cu exposure pathways, but for the bivalves Spisula trigonella and Tellina deltoidalis, toxicity occurred primarily by exposure to dissolved Cu. For relatively oxidized sediments that had moderate amounts of organic carbon (2.6-8.3% OC), silt (20-100%

Evaluating The Effectiveness Of Grassbed Treatments As Habitat For Juvenile Black Bass In A Drawdown Reservoir, D. R. Ratcliff, Wayne A. Wurtsbaugh, J. Zustak

Watershed Sciences Faculty Publications

Many reservoirs in arid regions experience highly variable water levels caused by seasonal inflow fluctuations and designated outflow requirements. At Shasta Lake, California, managers plant cereal-grain grassbeds on exposed drawdown shorelines to increase juvenile fish habitat, localize productivity, and increase invertebrate fish prey. To determine the efficacy of these plantings, the abundance of juvenile black basses Micropterus spp. (20–55 mm standard length) and the amount of periphyton and macroinvertebrate prey were compared among three treatment types: (1) planted grassbeds of cereal barley Hordeum vulgare; (2) artificial rope grassbeds, which eliminated physical deterioration and nutrient release; and (3) nonplanted control sites …

Population Status Of Acropora Corals In The Florida Keys, Steven Miller, Mark Chiappone, Leanne M. Rutten, Dione W. Swanson

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

Population declines of staghorn coral (Acropora cervicornis) and elkhorn coral (A. palmata) are often-cited examples of Caribbean reef change since the 1970s, due, in part, to disease and localized effects from storms and predation. Both corals were listed as threatened on the U.S. Endangered Species List based upon range-wide decline and poor recovery. A spatially intensive survey undertaken in the Florida Keys of Acropora corals quantified habitat distribution, colony abundance, size, and condition at 235 sites spanning over 200 km in 2007. A two-stage stratified sampling design using belt transects incorporated cross-shelf habitats and no-fishing management …

Stony Coral Species Diversity And Cover In The Florida Keys Using Design-Based Sampling, Leanne M. Rutten, Mark Chiappone, Dione W. Swanson, Steven Miller

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

Large-scale sampling of stony coral species richness, species distribution, and cover was undertaken at 423 Florida Keys sites between Miami and SW of Key West during 2005 and 2007. A two-stage, stratified random sampling design employed belt transects to enumerate numbers of species and point-intercept surveys to quantify cover. The sampling design incorporated ten reef and hard-bottom habitats from < 1 m to 27 m depth, as well as oceanographic regions and areas inside and outside of protected management zones. These data provide insights into the spatial extent and factors influencing stony coral biodiversity. For stony corals, a pool of ~50 taxa encompassing the Orders Milleporina and Scleractinia, including species and morphotypes, was recorded. Significant differences were found in species richness and cover among cross-shelf habitats, with great values on inner shelf margin patch reefs, followed by deeper fore-reef slope habitats that extended to the 27 m depth limit sampled. In contrast, the shallow fore-reef, especially in areas historically dominated by the branching coral Acropora palmata, yielded relatively low numbers of species and cover that are presently dominated by smaller, brooding corals such as Porites astreoides and Favia fragum.

Behavior And Ecological Interactions Of Larval Odonata, Clay L. Pierce, Philip H. Crowley, Dan M. Johnson

Clay L. Pierce

Enallagma aspersum and E. traviatum (Odonata: Coenagrionidae) are the most abundant larval odonates in Bays Mountain Park (Sullivan County, Tennessee, USA), although their spatial distributions are essentially nonoverlapping. E. traviatum coexists with insectivorous fish in a small lake, whereas E. aspersum is restricted to a small fishless pond nearby. Behavioral observations revealed that E. aspersum larvae were more active than E. traviatum, and tended to occupy more conspicuous positions. E. aspersum also engaged in more confrontations than E. traviatum, especially at higher density. In laboratorye xperimentsw ith juvenile bluegills( Lepomism acrochirusa) s predators,E . aspersum larvae were more vulnerable to …