Marine Biology Commons^™

Time Series Modeling To Ascertain Age In Fisheries Management, Kathleen Sue Kirch

OES Theses and Dissertations

The ability to assign accurate ages of fish is important to fisheries management. Accurate ageing allows for the most reliable age-based models to be used to support sustainability and maximize economic benefit. Structures used to age include bones, scales, and most commonly ear bones (otoliths). Assigning age relies on validating putative annual marks by evaluating accretional material laid down in patterns in fish otoliths, typically by marginal increment analysis. These patterns often take the shape of a sawtooth wave with an abrupt drop in accretion yearly to form an annual band and are typically validated qualitatively. Researchers have shown keen …

Targeting Ocean Conservation Outcomes Through Threat Reduction, Joseph A. Turner, Malcolm Starkey, Nicholas K. Dulvy, Frank Hawkins, Louise Mair, Adeline Serckx, Thomas Brooks, Beth Polidoro, Stuart H. M. Butchart, Kent Carpenter, Minna Epps, Rima W. Jabado, Nicholas B. W. Macfarlane, Leon Bennun

Biological Sciences Faculty Publications

Nations have committed to reductions in the global rate of species extinctions through the Sustainable Development Goals 14 and 15, for ocean and terrestrial species, respectively. Biodiversity loss is worsening despite rapid growth in the number and extent of protected areas, both at sea and on land. Resolving this requires targeting the locations and actions that will deliver positive conservation outcomes for biodiversity. The Species Threat Abatement and Restoration (STAR) metric, developed by a consortium of experts, quantifies the contributions that abating threats and restoring habitats in specific places offer towards reducing extinction risk based on the IUCN Red List …

Margalefidinium Polykrikoides Cyst Resuspension In The Lafayette River, A Sub-Tributary Of The Chesapeake Bay, Gabrielle Greaney, Eduardo Perez Vega, Katherine Crider, Dreux Chappell, Kimberly Powell, Richard Hale, Peter Bernhardt, Margaret Mulholland

Undergraduate Research Symposium

Harmful Algal Blooms are a collection of algae in a body of water that can cause serious environmental issues and health problems in both people and aquatic organisms. Dinoflagellates are microscopic, unicellular, and eukaryotic organisms that are well known for forming harmful algal blooms because of eutrophication. Coastal Virginia suffers from HABs in the Chesapeake Bay and its tributaries. A common species of dinoflagellate, known as Margalefidinium polykrikoides exists in the Chesapeake Bay. The purpose of this study is to determine if sediment resuspension produced by wind generated surface gravity waves cause cysts (dinoflagellate resting stages) to be suspended into …

A Multi-Taxon Analysis Of European Red Lists Reveal Major Threats To Biodiversity, Axel Hochkirch, Melanie Bilz, Catarina C. Ferreira, Anja Danielczak, David Allen, Ana Nieto, Carlo Rondinini, Kate Harding, Craig Hilton-Taylor, Caroline M. Pollock, Mary Seddon, Jean-Christophe Vié, Keith N. A. Alexander, Emily Beech, Manuel Biscoito, Yoan Braud, Ian J. Burfield, Filippo Maria Buzzetti, Marta Cálix, Kent E. Carpenter, Ning Labbish Chao, Dragan Chobanov, Maarten J. M. Christenhusz, Bruce B. Collette, Mia T. Comeros-Raynal, Neil Cox, Matthew Craig, Annabelle Cuttelod, William R. T. Darwall, Benoit Dodelin, Nicholas K. Dulvy, Eve Englefield, Michael F. Fay, Nicholas Fettes, Jörg Freyhof, Silvia García, Mariana García Criado, Michael Harvey, Nick Hodgetts, Christina Ieronymidou, Vincent J. Kalkman, Shelagh P. Kell, James Kemp, Sonia Khela, Richard V. Lansdown, Julia M. Lawson, Danna J. Leaman, Joana Magos Brehm, Nigel Maxted, Rebecca M. Miller, Eike Neubert, Baudewijn Odé, David Pollard, Riley Pollom, Rob Pople, Juan José Presa Asensio, Gina M. Ralph, Hassan Rankou, Malin Rivers, Stuart P. M. Roberts, Barry Russell, Alexander Sennikov, Fabien Soldati, Anna Staneva, Emilie Stump, Andy Symes, Dmitry Telnov, Helen Temple, Andrew Terry, Anastasiya Timoshyna, Chris Van Swaay, Henry Väre, Rachel H. L. Walls, Luc Willemse, Brett Wilson, Jemma Window, Emma G. E. Wright, Thomas Zuna-Kratky

Biological Sciences Faculty Publications

Biodiversity loss is a major global challenge and minimizing extinction rates is the goal of several multilateral environmental agreements. Policy decisions require comprehensive, spatially explicit information on species’ distributions and threats. We present an analysis of the conservation status of 14,669 European terrestrial, freshwater and marine species (ca. 10% of the continental fauna and flora), including all vertebrates and selected groups of invertebrates and plants. Our results reveal that 19% of European species are threatened with extinction, with higher extinction risks for plants (27%) and invertebrates (24%) compared to vertebrates (18%). These numbers exceed recent IPBES (Intergovernmental Platform on Biodiversity …

Atlantic Surfclam (Spisula Solidissima) Population Demographics And Distribution Along The Middle Atlantic Bight, Mauricio González Díaz

OES Theses and Dissertations

The Atlantic surfclam (Spisula solidissima) is a long-lived benthic biomass dominant organism that occurs on the Middle Atlantic Bight (MAB) continental shelf between 10 m and 50 m. Trends in Atlantic surfclam population specific growth and mortality rates were analyzed using four decades of age and length observations obtained from NOAA stock surveys from the 1980s to 2010s in six regions distributed along the MAB. Atlantic surfclam specific growth rates and asymptotic lengths were estimated from the age and length observations using the von Bertalanffy growth model. The analysis showed that the Atlantic surfclam median asymptotic length in …

Monitoring Extinction Risk And Threats Of The World's Fishes Based On The Sampled Red List Index, Rafael Miranda, Imanol Miqueleiz, William Darwall, Catherine Sayer, Nicholas K. Dulvy, Kent E. Carpenter, Beth Polidoro, Nadia Dewhurst-Richman, Caroline Pollock, Craig Hilton-Taylor, Robin Freeman, Ben Collen, Monika Böhm

Biological Sciences Faculty Publications

Global biodiversitytargets require us to identify species at risk of extinction and quantify status and trends of biodiversity. The Red List Index (RLI) tracks trends in the conservation status of entire species groups over time by monitoring changes in categories assigned to species. Here, we calculate this index for the world’s fishes in 2010, using a sampled approach to the RLI based on a randomly selected sample of 1,500 species, and also present RLI splits for freshwater and marine systems separately. We further compare specific traits of a worldwide fish list to our sample to assess its representativeness. Overall, 15.1% …

Habitat Restoration Restores Underwater Soundscapes And Larval Recruitment, Jack Butler, Emily R. Anderson, Mark J. Butler

Biological Sciences Faculty Publications

Habitat degradation alters many ecosystem processes, and the potential for the reestablishment of ecosystem function through restoration is an area of active research. Among marine systems, coastal habitats are particularly vulnerable to anthropogenic degradation and, in response, are the focus of marine ecological restoration. One of the crucial functions of structurally complex coastal habitats (e.g., saltmarshes, seagrass meadows, kelp forests, coral reefs) are as nurseries to coastal and offshore species, many of whose larvae utilize sound to locate suitable nursery habitat. However, the effect of habitat degradation and subsequent restoration on underwater soundscapes and their function as navigational cues for …

A Trait‐Based Framework For Assessing The Vulnerability Of Marine Species To Human Impacts, Nathalie Butt, Benjamin S. Halpern, Casey S. O'Hara, A. Louise Allcock, Beth Polidoro, Samantha Sherman, Maria Byrne, Charles Birkeland, Ross G. Dwyer, Melanie Frazier, Bradley K. Woodworth, Claudia P. Arango, Michael J. Kingsford, Vinay Udyawer, Pat Hutchings, Elliot Scanes, Emily Jane Mcclaren, Sara M. Maxwell, Guillermo Diaz-Pulido, Emma Dugan, Blake Alexander Simmons, Amelia S. Wenger, Christi Linardich, Carissa J. Klein

Biological Sciences Faculty Publications

Marine species and ecosystems are widely affected by anthropogenic stressors, ranging from pollution and fishing to climate change. Comprehensive assessments of how species and ecosystems are impacted by anthropogenic stressors are critical for guiding conservation and management investments. Previous global risk or vulnerability assessments have focused on marine habitats, or on limited taxa or specific regions. However, information about the susceptibility of marine species across a range of taxa to different stressors everywhere is required to predict how marine biodiversity will respond to human pressures. We present a novel framework that uses life-history traits to assess species’ vulnerability to a …

Nutrient Improvements In Chesapeake Bay: Direct Effect Of Load Reductions And Implications For Coastal Management, Rebecca R. Murphy, Jennifer Keisman, Jon Harcum, Renee R. Karrh, Mike Lane, Elgin S. Perry, Qian Zhang

Biological Sciences Faculty Publications

In Chesapeake Bay in the United States, decades of management efforts have resulted in modest reductions of nutrient loads from the watershed, but the corresponding improvements in estuarine water quality have not consistently followed. Generalized additive models were used to directly link river flows and nutrient loads from the watershed to nutrient trends in the estuary on a station-by-station basis, which allowed for identification of exactly when and where responses are happening. Results show that Chesapeake Bay’s total nitrogen and total phosphorus conditions are mostly improving after accounting for variation in freshwater flow. Almost all of these improving nutrient concentrations …

Mismatches In Scale Between Highly Mobile Marine Megafauna And Marine Protected Areas, Melinda G. Conners, Nicholas B. Sisson, Pierre D. Agamboue, Philip W. Atkinson, Alastair M.M. Baylis, Scott R. Benson, Barbara A. Block, Steven J. Bograd, Pablo Bordino, W. D. Bowen, Paul Brickle, Ignacio M. Bruno, Victoria González Carman, Cory D. Champagne, Daniel E. Crocker, Daniel P. Costa, Tiffany M. Dawson, Tomohiro Deguchi, Heidi Dewar, Philip D. Doherty, Tomo Eguchi, Angela Formia, Brendan J. Godley, Rachel T. Graham, Christian Gredzens, Kristen M. Hart, Lucy A. Hawkes, Suzanne Henderson, Robert William Henry Iii, Luis A. Hückstädt, Ladd M. Irvine, Sarah S. Kienle, Carey E. Kuhn, Damian Lidgard, Stephanie A. Loredo, Bruce R. Mate, Kristian Metcalfe, Jacob Nzegoue, Carmen K. Kouerey Oliwina, Rachel A. Orben, Kiyoaki Ozaki, Richard Parnell, Elizabeth P. Pike, Patrick W. Robinson, Howard C. Rosenbaum, Fumio Sato, Scott A. Shaffer, Donna J. Shaver, Samantha E. Simmons, Brian J. Smith, Guy-Philippe Sounguet, Robert M. Suryan, David R. Thompson, Megan Tierney, Dominic Tilley, Hillary S. Young, Victoria Warwick-Evans, Michael J. Weise, Randall S. Wells, Bradley P. Wilkinson, Matthew J. Witt, Sarah M. Maxwell

Biological Sciences Faculty Publications

Marine protected areas (MPAs), particularly large MPAs, are increasing in number and size around the globe in part to facilitate the conservation of marine megafauna under the assumption that large-scale MPAs better align with vagile life histories; however, this alignment is not well established. Using a global tracking dataset from 36 species across five taxa, chosen to reflect the span of home range size in highly mobile marine megafauna, we show most MPAs are too small to encompass complete home ranges of most species. Based on size alone, 40% of existing MPAs could encompass the home ranges of the smallest …

Tying Policy To System: Does The Ross Sea Region Marine Reserve Protect Transport Pathways Connecting The Life History Of Antarctic Toothfish?, Julian Ashford, Michael Dinniman, Cassandra Brooks, Lian Wei, Guoping Zhu

OES Faculty Publications

A central objective of the Ross Sea region Marine Protected Area (MPA) is to protect areas important to the life cycle of Antarctic toothfish (Dissostichus mawsoni), a top fish predator and by far the region’s most important commercial species. Juvenile toothfish predominate in deep basins along the inner continental shelf, whereas adults are found mostly along the continental slope and spawning areas on the Pacific-Antarctic Ridge. The inner basins connect to the continental slope via glacial troughs and predictable transport along each trough results in exchange with the Antarctic Slope Current as it flows westward. From the slope, …

Overfishing Drives Over One-Third Of All Sharks And Rays Toward A Global Extinction Crisis, Nicholas K. Dulvy, Nathan Pacoureau, Cassandra L. Rigby, Riley A. Pollom, Rima W. Jabado, David A. Ebert, Brittany Finucci, Caroline M. Pollock, Jessica Cheok, Danielle H. Derrick, Katelyn B. Herman, C. Samantha Sherman, Wade J. Vanderwright, Julia M. Lawson, Rachel H.L. Walls, John K. Carlson, Patricia Charvet, Kinattumkara K. Bineesh, Daniel Fernando, Gina M. Ralph, Jay H. Matsushiba, Craig Hilton-Taylor, Sonja V. Fordham, Colin A. Simpfendorfer

Biological Sciences Faculty Publications

The scale and drivers of marine biodiversity loss are being revealed by the International Union for Conservation of Nature (IUCN) Red List assessment process. We present the first global reassessment of 1,199 species in Class Chondrichthyes-sharks, rays, and chimeras. The first global assessment (in 2014) concluded that one-quarter (24%) of species were threatened. Now, 391 (32.6%) species are threatened with extinction. When this percentage of threat is applied to Data Deficient species, more than one-third (37.5%) of chondrichthyans are estimated to be threatened, with much of this change resulting from new information. Three species are Critically Endangered (Possibly Extinct), representing …

Variation In Coral Thermotolerance Across A Pollution Gradient Erodes As Coral Symbionts Shift To More Heat-Tolerant Genera, Melissa S. Naugle, Thomas A. Oliver, Daniel J. Barshis, Ruth D. Gates, Cheryl A. Logan

Biological Sciences Faculty Publications

Phenotypic plasticity is one mechanism whereby species may cope with stressful environmental changes associated with climate change. Reef building corals present a good model for studying phenotypic plasticity because they have experienced rapid climate-driven declines in recent decades (within a single generation of many corals), often with differential survival among individuals during heat stress. Underlying differences in thermotolerance may be driven by differences in baseline levels of environmental stress, including pollution stress. To examine this possibility, acute heat stress experiments were conducted on Acropora hyacinthus from 10 sites around Tutuila, American Samoa with differing nutrient pollution impact. A threshold-based heat …

First Record Of Blacknape Large-Eye Bream Gymnocranius Satoi (Perciformes: Lethrinidae) In The Philippines, Nicko Amor Flores, Jade Tifany Rey, Jeffrey T. Williams, Kent Carpenter, Mudjekeewis Santos

Biological Sciences Faculty Publications

The Philippines has been regarded as the center of the center of marine shorefish biodiversity, having the highest number of fish species per square area in the world. The blacknape large-eye bream, Gymnocranius satoi, has been reported to occur from Southern Japan, Taiwan to Northwestern Australia and to the Coral Sea, but has not previously been recorded from the Philippines. From 2011 – 2019, the National Fisheries Research and Development Institute (NFRDI) collaborated with the National Museum of Natural History of the Smithsonian Institution (NMNH/SI), USA, and the Old Dominion University (ODU), Virgina, USA, to inventory all commercial fish …

Global Conservation Status Of Croaker And Drum (Family: Sciaenidae) And Role Of The Maw Trade, Claire E. Gorman

Biological Sciences Theses & Dissertations

Understanding threats and drivers of extinction risk is critical to conserving marine biodiversity. Although marine bony fishes are some of the most diverse and abundant vertebrates in the world, overexploitation is the major threat to these taxa. Species in the family Sciaenidae are important marine resources in many parts of the world, supporting small- and large-scale fisheries for consumption and the international maw (dried swimbladder) trade. Sciaenids exhibit a diverse array of life history characteristics, such as high fecundity, large body size, formation of spawning aggregations, and longevity. Some characteristics increase their susceptibility to anthropogenic stressors. Despite being ecologically and …

Spatial Structuring And Life History Connectivity Of Antarctic Silverfish Along The Southern Continental Shelf Of The Weddell Sea, Jilda Alicia Caccavo, Julian R. Ashford, Svenja Ryan, Chiara Papetti, Michael Schröder, Lorenzo Zane

OES Faculty Publications

A multi-disciplinary approach was employed to examine a physical-biological population hypothesis for a critical forage species, the Antarctic silverfish Pleuragramma antarctica. Caccavo et al. (2018; Sci Rep 8:17856) had shown strong gene flow along the westward Antarctic Slope Current, in addition to spatially recurring length modes that provided evidence for episodic connectivity. In this paper, otolith nucleus chemistry from a subset of fish collected in the southern Weddell Sea as part of a hydrographic survey of the Filchner Trough system was used to test between connectivity scenarios. Nucleus chemistry, which reflects environmental exposure during early life, showed significant …

Genetic Patterns In Peripheral Marine Populations Of The Fusilier Fish Caesio Cuning Within The Kuroshio Current, Amanda S. Ackiss, Christopher E. Bird, Yuichi Akita, Mudjekeewis D. Santos, Katsunori Tachihara, Kent E. Carpenter

Biological Sciences Faculty Publications

Aim: Mayr’s central‐peripheral population model (CCPM) describes the marked differences between central and peripheral populations in genetic diversity, gene flow, and census size. When isolation leads to genetic divergence, these peripheral populations have high evolutionary value and can influence biogeographic patterns. In tropical marine species with pelagic larvae, powerful western‐boundary currents have great potential to shape the genetic characteristics of peripheral populations at latitudinal extremes. We tested for the genetic patterns expected by the CCPM in peripheral populations that are located within the Kuroshio Current for the Indo‐Pacific reef fish, Caesio cuning.

Methods: We used a panel of 2,677 …

Global Conservation Status Of Marine Pufferfishes (Tetraodontiformes: Tetraodontidae), Emilie Stump, Gina M. Ralph, Mia T. Comeros-Raynal, Keiichi Matsuura, Kent E. Carpenter

Biological Sciences Faculty Publications

Puffers are biologically and ecologically fascinating fishes best known for their unique morphology and arsenal of defenses including inflation and bioaccumulation of deadly neurotoxins. These fishes are also commercially, culturally, and ecologically important in many regions. One-hundred-and-fifty-one species of marine puffers were assessed against the International Union for Conservation of Nature (IUCN) Red List Criteria at a 2011 workshop held in Xiamen, China. Here we present the first comprehensive review of puffer geographic and depth distribution, use and trade, and habitats and ecology and a summary of the global conservation status of marine puffers, determined by applying the International Union …

Composition Of Dissolved Organic Matter In Pore Waters Of Anoxic Marine Sediments Analyzed By 1h Nuclear Magnetic Resonance Spectroscopy, Christina A. Fox, Hussain A. Abdulla, David J. Burdige, James P. Lewicki, Tomoko Komada

OES Faculty Publications

Marine sediments are globally significant sources of dissolved organic matter (DOM) to the oceans, but the biogeochemical role of pore-water DOM in the benthic and marine carbon cycles remains unclear due to a lack of understanding about the molecular composition of DOM. To help fill this knowledge gap, we used 1H nuclear magnetic resonance (NMR) spectroscopy to examine depth variability in the composition of pore-water DOM in anoxic sediments of Santa Barbara Basin, California Borderland. Proton detected spectra were acquired on whole samples without pre-concentration to avoid preclusion of any DOM components from the analytical window. Broad unresolved resonance (operationally …

Blooms Of Dinoflagellate Mixotrophs In A Lower Chesapeake Bay Tributary: Carbon And Nitrogen Uptake Over Diurnal, Seasonal, And Interannual Timescales, Margaret R. Mulholland, Ryan Morse, Todd Egerton, Peter W. Bernhardt, K. C. Filippino

OES Faculty Publications

A multi-year study was conducted in the eutrophic Lafayette River, a sub-tributary of the lower Chesapeake Bay during which uptake of inorganic and organic nitrogen (N) and C compounds was measured during multiple seasons and years when different dinoflagellate species were dominant. Seasonal dinoflagellate blooms included a variety of mixotrophic dinoflagellates including Heterocapsa triquetra in the late winter, Prorocentrum minimum in the spring, Akashiwo sanguinea in the early summer, and Scrippsiella trochoidea and Cochlodinium polykrikoides in late summer and fall. Results showed that no single N source fueled algal growth, rather rates of N and C uptake varied on seasonal …

Sea Turtles And Survivability In Demersal Trawl Fisheries: Do Comatose Olive Ridley Sea Turtles Survive Post-Release?, Sara M. Maxwell, Matthew J. Witt, Gaspard Abitsi, Marie Pierre Aboro, Pierre Didier Agamboue, Georges Mba Asseko, Francois Boussamba, Emmanuel Chartain, Micheline Schummer Gnandji, Brice Didier Koumba Mabert

Biological Sciences Faculty Publications

Incidental capture of air‑breathing species in fishing gear is a major source of mortality for many threatened populations. Even when individuals are discarded alive, they may not survive due to direct injury, or due to more cryptic internal physiological injury such as decompression sickness. Post‑release mortality, however, can be difficult to determine. In this pilot study, we deployed survivorship pop‑up archival tags (sPAT) (n = 3) for an air‑breathing species, the olive ridley sea turtle (Lepidochelys olivacea), one of the first studies to do so. We found that at least two of the three turtles survived after being …

Characterizing Habitat Suitability For A Central‐Place Forager In A Dynamic Marine Environment, Dana K. Briscoe, Sabrina Fossette, Kylie L. Scales, Elliott L. Hazen, Steven J. Bograd, Sara M. Maxwell, Elizabeth A. Mchuon, Patrick W. Robibson, Carey Kuhn, Daniel P. Costa, Larry B. Crowder, Rebecca L. Lewison

Biological Sciences Faculty Publications

Characterizing habitat suitability for a marine predator requires an understanding of the environmental heterogeneity and variability over the range in which a population moves during a particular life cycle. Female California sea lions (Zalophus californianus) are central‐place foragers and are particularly constrained while provisioning their young. During this time, habitat selection is a function of prey availability and proximity to the rookery, which has important implications for reproductive and population success. We explore how lactating females may select habitat and respond to environmental variability over broad spatial and temporal scales within the California Current System. We combine near‐real‐time …

High Frequency Temperature Variability Reduces The Risk Of Coral Bleaching, Aryan Safaie, Nyssa J. Silbiger, Timothy R. Mcclanahan, Geno Pawlak, Daniel J. Barshis, James L. Hench, Gareth J. Williams, Kristen A. Davis

Biological Sciences Faculty Publications

Coral bleaching is the detrimental expulsion of algal symbionts from their cnidarian hosts, and predominantly occurs when corals are exposed to thermal stress. The incidence and severity of bleaching is often spatially heterogeneous within reef-scales (km), and is therefore not predictable using conventional remote sensing products. Here, we systematically assess the relationship between in situ measurements of 20 environmental variables, along with seven remotely sensed SST thermal stress metrics, and 81 observed bleaching events at coral reef locations spanning five major reef regions globally. We find that high-frequency temperature variability (i.e., daily temperature range) was the most influential factor in …

The Spatial Context Of “Winning” In Mpa Network Design: Location Matters, Andrew S. Kough, Claire B. Paris, Mark J. Butler Iv

Biological Sciences Faculty Publications

(First paragraph) Chollett et al. (2017) make the case that a local network of marine protected areas (MPAs) enhances fisheries for Caribbean spiny lobster (Panulirus argus) off the coast of Honduras. However, their simulation focused on one ecoregion where self-recruitment is predicted to be among the highest in the Caribbean (Cowen, Paris, & Srinivasan, 2006). The shallow banks and scattered cays of the Honduran-Nicaraguan Rise, separating the Cayman and Colombian basins, create an obstacle to the powerful southern Caribbean jet (Richardson, 2005), fostering an ideal location for topographically steered eddies and larval retention. Local management,whether based on traditional …

Distributions Of Krill And Antarctic Silverfish And Correlations With Environmental Variables In The Western Ross Sea, Antarctica, L. Brynn Davis, Eileen E. Hofmann, John M. Klinck, Andrea Piñones, Michael S. Dinniman

CCPO Publications

Antarctic krill Euphausia superba, crystal krill E. crystallorophias, and Antarctic silverfish Pleuragramma antarctica are key mid-trophic level species in the Ross Sea, connecting primary production to the upper trophic levels. Distributions of these species were constructed from observations made in the western Ross Sea from 1988 to 2004. Distributions of environmental conditions were obtained from a 5-km resolution circulation model (temperature, mixed layer depth, surface speed) and satellite-derived observations (chlorophyll, sea ice cover). A hierarchy of statistical methods determined correlations and relationships between species and environmental conditions. Each species occupies a localized habitat defined by different environmental characteristics. …

Life History And Management Methods For Blueline Tilefish (Caulolatilus Microps) From The United States Mid-Atlantic Region, Michael A. Schmidtke

OES Theses and Dissertations

Blueline tilefish (Caulolatilus microps) have recently undergone an increase in landings from waters off the US Mid-Atlantic region (Virginia-Massachusetts). Currently, life history characteristics of blueline tilefish in this area are undescribed. Additionally, appropriate indices of population abundance are not available for this region, necessitating the use of data-limited management methods to set restrictions for harvest of blueline tilefish in this area. This dissertation describes growth and reproductive characteristics of blueline tilefish caught off the coast of Virginia and explores improvements of data-limited management methods that have been applied to blueline tilefish in the US Mid-Atlantic. Blueline tilefish from …

Determining Critical Internesting And Foraging Habitats For The Conservation Of Sea Turtles In Gabon, Africa Using Satellite Tracking And Stable Isotope Analysis, Tiffany M. Dawson

Biological Sciences Theses & Dissertations

Understanding the horizontal and vertical habitat of olive ridley sea turtles (Lepidochelys olivacea), a threatened species, is critical for determining regions of protection that may effectively reduce bycatch, the largest threat to this species. Satellite transmitters were used to determine the movement and dive behavior of 21 female olive ridley turtles tagged in Pongara National Park, Gabon during the 2012, 2013, and 2015 nesting seasons. A switching state space model was used to filter the tracking data and categorize the internesting and post-nesting movements. Gridded utilization distribution (UD) home range analysis of tracking data revealed that the entire core habitat …

Experimental Impacts Of Climate Warming And Ocean Carbonation On Eelgrass Zostera Marina, Richard C. Zimmerman, Victoria J. Hill, Malee Jinuntuya, Billur Celebi, David Ruble, Miranda Smith, Tiffany Cedeno, W. Mark Swingle

OES Faculty Publications

CO₂ is a critical and potentially limiting substrate for photosynthesis of both terrestrial and aquatic ecosystems. In addition to being a climate-warming greenhouse gas, increasing concentrations of CO₂ will dissolve in the oceans, eliciting both negative and positive responses among organisms in a process commonly known as ocean acidification. The dissolution of CO₂ into ocean surface waters, however, also increases its availability for photosynthesis, to which the highly successful, and ecologically important, seagrasses respond positively. Thus, the process might be more accurately characterized as ocean carbonation. This experiment demonstrated that CO₂ stimulation of primary production enhances …

Multiple Mating By Females In The Chesapeake Bay Blue Crab Callinectes Sapidus Population, S. Wells, J. Mcconaugha, L. Horth

OES Faculty Publications

Mature females of the Chesapeake Bay (USA) blue crab Callinectes sapidus population mate multiple times. Microsatellite DNA analysis of sperm stored in the spermathecae has shown that virtually all (~97%, 104 out of 107) females collected in a 2009−2010 study mated with at least 2 males. Enumeration of stored sperm revealed that despite multiple mating, some females did not have enough sperm to fulfill their lifetime reproductive potential, suggesting that female blue crabs may experience varying levels of sperm limitation. This could result from multiple factors. The average body size of males in the population has decreased, which reduces the …

Informing Marine Protected Area Designation And Management For Nesting Olive Ridley Sea Turtles Using Satellite Tracking, Tiffany M. Dawson, Angela Formia, Pierre D. Agamboué, Georges M. Asseko, François Boussamba, Floriane Cardiec, Emmanuel Chartrain, Philip D. Doherty, J. Michael Fay, Brendan J. Godley, Francis Lambert, Brice D. Koumba Mabert, Jean C. Manfoumbi, Kristian Metcalfe, Gianna Minton, Ivan Ndanga, Jacob Nzegoue, Carmen K. Kouerey Oliwina, Philippe Du Plessis, Guy-Philippe Sounguet, Dominic Tilley, Matthew J. Witt, Sara M. Maxwell

Biological Sciences Faculty Publications

Understanding the horizontal and vertical habitat of olive ridley sea turtles (Lepidochelys olivacea), a threatened species, is critical for determining regions for protection and relevant gear modifications that may effectively reduce bycatch, the largest threat to this species. Satellite transmitters were used to determine the movement and dive behavior of 21 female olive ridley turtles tagged in Pongara National Park, Gabon during the 2012, 2013, and 2015 nesting seasons. A switching state-space model was used to filter the tracking data and categorize the internesting and post-nesting movements. Gridded utilization distribution (UD) home range analysis of tracking data revealed …