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Trophic Ecology Of Oxygen Minimum Zone Zooplankton Revealed By Carbon And Nitrogen Stable Isotopes, Rebecca Williams

Open Access Dissertations

Oxygen minimum zones (OMZs) are areas in which midwater oxygen concentration can be significantly lower than in non OMZ areas at comparable depths. OMZs are of great interest because of the limits oxygen availability places on life. The potential for OMZ expansion with warming of the oceans has refocused attention on the importance of these areas and their potential impacts on the global carbon cycle. The large open ocean OMZs of the Eastern Tropical Pacific and Arabian Sea are notable for their size, thickness, and the intensity of oxygen depletion (

Here, I use measurements of natural abundance carbon and …

Characterizing The Benthic Invertebrate Communities Of The Mixed-Coarse Intertidal Habitat In Boston Harbor, Elizabeth N. Eddy

Open Access Master's Theses

The Boston Harbor Islands National Recreation Area (BOHA) has an extensive intertidal zone, with 47% of the area composed of mixed-coarse substrate. Given anticipated climate change impacts such as sea level rise and ocean warming, and other stressors associated with the urban environment, the critical ecosystem functions provided by the dominant yet largely understudied mixed-coarse habitat are likely to be altered. To evaluate the benthic invertebrate communities of BOHA and to determine what environmental factors of the mixed-coarse substrate affect community structure, 87 sampling sites were distributed between wave-exposed and wave-protected shorelines between mean higher high water and mean lower …

Quantifying The Effects Of Tidal Restrictions And Plant Invasions On Resident Fish In Atlantic Coast Salt Marshes, Kimberly Lellis Dibble

Open Access Dissertations

This research investigates the combined effects of tidal restriction and Phragmites australis invasion on habitat quality for marsh fauna across a large geographic area while evaluating the reversal of those effects through ecological restoration. We used meta-analytic tools and published literature to examine differences in the quantity, condition, and diversity of fauna in invaded and restored marshes relative to uninvaded (reference) marshes in the mid-Atlantic and in New England. In addition, we collected data for two projects designed to move beyond the collection of community data (e.g., density, richness, as included in the meta-analysis) to assess the functional response of …

Biodiversity And Ecosystem Function In The Gulf Of Maine: Pattern And Role Of Zooplankton And Pelagic Nekton, Catherine L. Johnson, Jeffrey A. Runge, K. Alexandra Curtis, Edward G. Durbin, Jonathan A. Hare, Lewis S. Incze, Jason S. Link, Gary D. Melvin, Todd D. O'Brien, Lou Van Guelpen

Graduate School of Oceanography Faculty Publications

This paper forms part of a broader overview of biodiversity of marine life in the Gulf of Maine area (GoMA), facilitated by the GoMA Census of Marine Life program. It synthesizes current data on species diversity of zooplankton and pelagic nekton, including compilation of observed species and descriptions of seasonal, regional and cross-shelf diversity patterns. Zooplankton diversity in the GoMA is characterized by spatial differences in community composition among the neritic environment, the coastal shelf, and deep offshore waters. Copepod diversity increased with depth on the Scotian Shelf. On the coastal shelf of the western Gulf of Maine, the number …

Influence Of Industrial Activities On The Spatial Distribution Of Wildlife In Murchison Falls National Park, Uganda, Samuel Ayebare

Open Access Master's Theses

Activities carried out by resource extraction industries in and adjacent to protected areas have increased the risk to biodiversity conservation in different parts of the world. Oil and natural gas developments in the Albertine rift, one of Africa’s biodiversity hotspots, have raised concerns about the potential impacts to wildlife populations and the associated land-cover change. The influence of oil and gas industrial activities on the spatial distribution of wildlife in Murchison Falls National Park was examined by conducting wildlife surveys along 2-km long transects that radiated away from well pads and access roads. The position of large mammal sightings were …

Highly Variable Acquisition Rates Of Ixodes Scapularis (Acari: Ixodidae) By Birds On An Atlantic Barrier Island, S. S. Mitra, P. A. Buckley, F. G. Buckley, Howard S. Ginsberg

Natural Resources Science Faculty Publications

Acquisition of ticks by bird hosts is a central process in the transmission cycles of many tick-borne zoonoses, but tick recruitment by birds has received little direct study. We documented acquisition of Ixodes scapularis Say on birds at Fire Island, NY, by removing ticks from mist-netted birds, and recording the number of ticks on birds recaptured within 4 d of release. Eight bird species acquired at least 0.8 ticks bird⁻¹ day⁻¹ during the seasonal peak for at least one age class of I. scapularis. Gray Catbirds, Eastern Towhees, Common Yellowthroats, and Northern Waterthrushes collectively accounted for 83% …

Predator Effects In Predator-Free Space: The Remote Effects Of Predators On Prey, John L. Orrock, Lawerence M. Dill, Andrew Sih, Johnathan H. Grabowski, Scott D. Peacor, Barbara L. Peckarsky, Evan L. Preisser, James R. Vonesh, Earl E. Werner

Biological Sciences Faculty Publications

Predators can have remote effects on prey populations that are connected by migration (i.e. prey metapopulations) because predator-mediated changes in prey behavior and abundance effectively transmit the impact of predators into predator-free prey populations. Behavioral changes in prey that might give rise to remote effects are altered rates of migration or activity in the presence of predation risk (called non-consumptive effects, fear- or μ-driven effects, and risk effects). Changes in prey abundance that may result in remote effects arise from changes in prey density due to direct predation (i.e. consumptive effects, also called N-driven effects and predation effects). Remote effects …

Ecological Boundary Detection Using Bayesian Areal Wombling, Matthew C. Fitzpatrick, Evan L. Preisser, Adam Porter, Joseph Elkinton, Lance A. Waller, Bradley P. Carlin, Aaron M. Ellison

Biological Sciences Faculty Publications

The study of ecological boundaries and their dynamics is of fundamental importance to much of ecology, biogeography, and evolution. Over the past two decades, boundary analysis (of which wombling is a subfield) has received considerable research attention, resulting in multiple approaches for the quantification of ecological boundaries. Nonetheless, few methods have been developed that can simultaneously (1) analyze spatially homogenized data sets (i.e., areal data in the form of polygons rather than point‐reference data); (2) account for spatial structure in these data and uncertainty associated with them; and (3) objectively assign probabilities to boundaries once detected. Here we describe the …

Phenotopic Plasticity Of Leaf Shape Along A Temperature Gradient In Acer Rubrum, Dana L. Royer, Laura A. Meyerson, Kevin M. Robertson, Jonathan M. Adams

Natural Resources Science Faculty Publications

Both phenotypic plasticity and genetic determination can be important for understanding how plants respond to environmental change. However, little is known about the plastic response of leaf teeth and leaf dissection to temperature. This gap is critical because these leaf traits are commonly used to reconstruct paleoclimate from fossils, and such studies tacitly assume that traits measured from fossils reflect the environment at the time of their deposition, even during periods of rapid climate change. We measured leaf size and shape in Acer rubrum derived from four seed sources with a broad temperature range and grown for two years in …

Bacterial Community Profiling Of The Eastern Oyster (Crassostrea Virginica): Comparison Of Culture-Dependent And Culture-Independent Outcomes, Kenneth J. La Valley, Steve Jones, Marta Gomez-Chiarri, Joseph Dealteris, Michael A. Rice

Fisheries, Animal and Veterinary Sciences Faculty Publications

Tissue-associated bacterial community profiles generated using a nested polymerase chain reaction–denaturing gradient gel electrophoresis (DGGE) approach and culture-dependent and culture-independent isolation techniques were compared. Oyster samples were collected from 2 harvest areas along the coast of Maine, in the United States. Profiles from both isolation strategies were evaluated using Sorensen’s index of similarity and cluster analysis of gel banding patterns. Culture independent profiles were further evaluated using the Shannon diversity index. In general, the culture-dependent strategy resulted in a greater number of bands within a profile. Bacterial DGGE profiles were found to be highly similar within an isolation strategy, with …

Revisiting The Classics: Considering Nonconsumptive Effects In Textbook Examples Of Predator–Prey Interactions, Barbara L. Peckarsky, Peter A. Abrams, Daniel I. Bolnick, Lawrence M. Dill, Jonathan H. Grabowski, Barney Luttberg, John L. Orrock, Scott D. Peacor, Evan L. Preisser, Oswald J. Schmitz, Geoffrey C. Trussell

Biological Sciences Faculty Publications

Predator effects on prey dynamics are conventionally studied by measuring changes in prey abundance attributed to consumption by predators. We revisit four classic examples of predator–prey systems often cited in textbooks and incorporate subsequent studies of nonconsumptive effects of predators (NCE), defined as changes in prey traits (e.g., behavior, growth, development) measured on an ecological time scale. Our review revealed that NCE were integral to explaining lynx–hare population dynamics in boreal forests, cascading effects of top predators in Wisconsin lakes, and cascading effects of killer whales and sea otters on kelp forests in nearshore marine habitats. The relative roles of …

From Individuals To Ecosystem Function: Toward An Integration Of Evolutionary And Ecosystem Ecology, Oswald J. Schmitz, Jonathan H. Garbowski, Barbara L. Peckarsky, Evan L. Preisser, Geoffrey C. Trussell, James R. Vonesh

Biological Sciences Faculty Publications

An important goal in ecology is developing general theory on how the species composition of ecosystems is related to ecosystem properties and functions. Progress on this front is limited partly because of the need to identify mechanisms controlling functions that are common to a wide range of ecosystem types. We propose that one general mechanism, rooted in the evolutionary ecology of all species, is adaptive foraging behavior in response to predation risk. To support our claim, we present two kinds of empirical evidence from plant‐based and detritus‐based food chains of terrestrial and aquatic ecosystems. The first kind comes from experiments …

Woodland Type And Spatial Distribution Of Nymphal Ixodes Scapularis (Acari: Ixodidae), Howard S. Ginsberg, Elyes Zhioua, Shaibal Mitra, James Fischer, P. A. Buckley, Frank Verret, H. Brian Underwood, Francine G. Buckley

Past Departments Faculty Publications (CELS)

Spatial distribution patterns of black-legged ticks, Ixodes scapularis, in deciduous and coniferous woodlands were studied by sampling ticks in different woodland types and at sites from which deer had been excluded and by quantifying movement patterns of tick host animals (mammals and birds) at the Lighthouse Tract, Fire Island, NY, from 1994 to 2000. Densities of nymphal ticks were greater in deciduous than coniferous woods in 3 of 7 yr. Only engorged ticks survived the winter, and overwintering survival of engorged larvae in experimental enclosures did not differ between deciduous and coniferous woods. Nymphs were not always most abundant …

Aspects Of Bacterial Community Ecology Within The American Oyster (Crassostrea Virginica), And Surveillance Of Post-Harvest Vibrio Vulnificus Occurrence, Kenneth John La Valley

Open Access Dissertations

This dissertation research addressed the fundamental question of what the general microbial flora within the oyster is and what influence depuration and relay have on bacterial communities in the oyster. Comparisons of bacterial community profiles were made using culture-dependent and culture-independent isolation techniques and a nested PCR-DGGE (Denaturing Gradient Gel Electrophoresis) approach. Differences in the composition of the bacterial community between culture-dependent and culture-independent profiles were detected. The effect of culture-based techniques is significant and results in a biased representation of community structure. This bias may be minimized for the oyster compared to the large differences typically detected between culturable …

A Comparative Evaluation Of The Habitat Value Of Shellfish Aquaculture Gear, Submerged Aquatic Vegetation And A Non-Vegetated Seabed, Joseph Dealteris, Brian D. Kilpatrick, Robert B. Rheault

Fisheries, Animal and Veterinary Sciences Faculty Publications

The habitat value of modified rack and bag, shellfish aquaculture gear (SAG) used for the grow-out phase of the American oyster, Crassostrea virginica, submerged aquatic vegetation (SAV), Zostera marina, and a shallow nonvegetated seabed (NVSB) was comparatively evaluated over a 1-year period in Pt. Judith Pond, a tidal estuary in Southern Rhode Island. Enclosure gear was used to sample the three ecotypes, and organisms (>5 mm) were identified, enumerated, and measured to the nearest millimeter. Abundances of marine organisms and species diversity indices were used as measures of the habitat value of these ecotypes within each season. Environmental …

Predicting Condition Of Small Estuarine Systems Along The United States' Atlantic Coast, Jeffrey W. Hollister

Open Access Dissertations

Anthropogenic activities are known to degrade the ecological condition of estuaries. Also, numerous studies find links between landscape structure and estuarine condition. From these relationships, it is possible to build predictive models of estuarine condition. In this study, I examined issues of data quality, scale, and statistical approach to developing predictive models of estuarine sediment metal concentrations in the Mid-Atlantic region of the United States. I assessed the accuracy of the National Land Cover Dataset (NLCD) at multiple scales by comparing it with reference data from Rhode Island and Massachusetts. Area of developed lands, agriculture, forest and water had acceptable …

Extent And Composition Of Open Coastal Sandplain Plant Communities Of The Cape Cod National Seashore, Evan L. Gwilliam

Open Access Master's Theses

Coastal sandplain heathlands and grasslands of the northeastern United States are globally rare habitat types that support a unique assemblage of plants and animals. This habitat is rapidly disappearing due to plant succession following cessation of land use, and coastal processes. I used interpretation of historical maps, aerial photography, GIS, and analysis of field data to examine vegetation dynamics and the impact of historic land use and coastal processes on the current extent and composition of coastal sandplain plant communities found within the Cape Cod National Seashore (CCNS). Currently, one third (244 ha) of the coastal heathland and grassland habitat …

The Relationship Between A Sense Of Community And Social Disorganization And Neighborhood Deprivation, Sharon Kingston

Open Access Dissertations

Empirical work on conditions in economically deprived neighborhoods, suggest that neighborhood conditions can exert negative effects human development even after accounting for individual characteristics of neighborhood residents. One of the most important theories regarding the ways in which neighborhood conditions impact behavior is the theory of social disorganization. Social disorganization posits that poverty and disorganizing social conditions interfere with the ability of neighborhood residents to form and enforce common social norms, leading to social problems (Byrne & Sampson, 1993, Sampson & Groves, 1989). Despite the utility of theories such as social disorganization, the measurement of important mediating variables between structural …

Pfiesteria: Review Of The Science And Identification Of Research Gaps. Report For The National Center For Environmental Health, Centers For Disease Control And Prevention, Jonathan Samett, Gary S. Bignami, Robert Feldman, William Hawkins, Jerry Neff, Theodore Smayda

Graduate School of Oceanography Faculty Publications

In connection with the CDC National Conference on Pfiesteria, a multidisciplinary panel evaluated Pfiesteria-related research. The panel set out what was known and what was not known about adverse effects of the organism on estuarine ecology, fish, and human health; assessed the methods used in Pfiesteria research; and offered suggestions to address data gaps. The panel's expertise covered dinoflagellate ecology; fish pathology and toxicology; laboratory measurement of toxins, epidemiology, and neurology. The panel evaluated peer-reviewed and non-peer-reviewed literature available through June 2000 in a systematic conceptual framework that moved from the source of exposure, through exposure research and dose, …

Assessing The Ecological Risk Of Toxic Chemicals On Coastal And Estuarine Ecosystems, Robert Kenneth Johnston

Open Access Dissertations

No abstract provided.

The Three Hundred And Thirty-Third Report Of The Curricular Affairs Committee: Proposal For A Bachelor Of Science Degree In Environmental Plant Biology, University Of Rhode Island Faculty Senate

Faculty Senate Bills

No abstract provided.

Timing Of Metamorphosis In A Freshwater Crustacean: Comparison With Anuran Models, Saran Twombly

Biological Sciences Faculty Publications

Many crustaceans have complex life cycles characterized by a metamorphosis, yet variation in metamorphic traits, and the causes and consequences of this variation, have rarely been examined. Food concentrations were changed during specific larval stages of the freshwater copepod Mesocyclops edax Forbes (Copepoda: Cyclopoida) to examine whether age and size at metamorphosis remain flexible or become fixed during the larval period. Results were compared to predictions of both flexible (the Wilbur—Collins model) and fixed (Leips—Travis model) rate models for the timing of amphibian metamorphosis. Age and size at metamorphosis were variable in all treatments, and age was always more variable …

Systematics Of Selected Species Of The Marine Diatom Genus Chaetoceros Ehrenberg 1844, Jan Elizabeth B. Rines

Open Access Dissertations

No abstract provided.

Seasonal Dynamics Of Gigaspora Gigantea And Associated Microorganisms In A Sand Dune, Pau-Ju Lee

Open Access Dissertations

No abstract provided.

Effects Of Crustacean Wastes On The Viability Of Beauveria Bassiana In Soil, Cheng-Jen Tsai

Open Access Dissertations

No abstract provided.

Ecology Of Oceanic Diatoms: Investigations Of Symbioses, Suspension And Growth Dynamics Of Selected Rhizosolenia Species, Tracy Alan Villareal

Open Access Dissertations

No abstract provided.

The Impact Of Natural And Induced Stress On Variation And Adaptation Within Populations Of Dennstaedtia Punctilobula (Michx.) Moore, Susan Chandler Lum Hammen

Open Access Dissertations

No abstract provided.

The Feeding Ecology Of The Genus Fissurella (Mollusca: Gastropoda) On Isla De Margarita, Venezuela, Craig Joseph Franz

Open Access Dissertations

No abstract provided.

Physiology And Ecology Of Vesicular-Arbuscular Mycorrhizal Fungi In Sand Dune Systems, Jane Natale Gemma

Open Access Dissertations

No abstract provided.

The Biology Of Chrysomelobia Labidomerae Eickwort, And Its Potential To Control The Colorado Potato Beetle (Parasitic Mite, Podapolipidae, Biological Control), Francis Andrew Drummond

Open Access Dissertations

No abstract provided.