Ecology and Evolutionary Biology Commons^™

Climate Drives The Geography Of Marine Consumption By Changing Predator Communities, M. A. Whalen, R.D. B. Whippo, J. J. Stachowicz, (...), Paige G. Ross, Et Al

VIMS Articles

The global distribution of primary production and consumption by humans (fisheries) is well-documented, but we have no map linking the central ecological process of consumption within food webs to temperature and other ecological drivers. Using standardized assays that span 105° of latitude on four continents, we show that rates of bait consumption by generalist predators in shallow marine ecosystems are tightly linked to both temperature and the composition of consumer assemblages. Unexpectedly, rates of consumption peaked at midlatitudes (25 to 35°) in both Northern and Southern Hemispheres across both seagrass and unvegetated sediment habitats. This pattern contrasts with terrestrial systems, …

A Multi-Scale Approach For Simulating Tidal Marsh Evolution, Karinna Nunez, Yinglong J. Zhang, Julie Herman, W. G. Reay, Carl Hershner

VIMS Articles

This study presents a new approach to modeling marsh evolution. The Tidal Marsh Model (TMM) has been developed as a module within the SCHISM (Semi-implicit Cross-scale Hydroscience Integrated System Model) framework. Some unique features of the TMM are dynamic rates, cross-scale simulations, and incorporation of anthropogenic stressors, which allow it to overcome many limitations that current marsh models possess. To evaluate model performance, the TMM was applied in Carter Creek and Taskinas Creek within the York River system (Virginia, USA). We assessed model outputs against field observations focusing on two main aspects: marsh boundary evolution and distribution of marsh sediments. …

Ecological Associations Of Littoraria Irrorata With Spartina Cynosuroides And Spartina Alterniflora, Caroline Mackenzie Failon, Serina Sebilian Wittyngham, David S. Johnson

VIMS Articles

It is well-documented that marsh periwinkles (Littoraria irrorata) consume and inhabit smooth cordgrass (Spartina alterniflora), but their interactions with big cordgrass (Spartina cynosuroides) remain unknown. Plant communities in mesohaline marshes will change as sea-level rise shifts species from salt-intolerant (e.g., S. cynosuroides) plants to salt-tolerant (e.g., S. alterniflora) ones. Therefore, understanding how L. irrorata interacts with different habitats provides insight into this species’ generalist nature and allows us to predict the potential impacts of changing plant communities on L. irrorata. We show, for the first time, that L. irrorata inhabits, climbs, …

Ecological Monitoring Program At Vims Esl - Annual Report 2018-2019, Paige G. Ross, Richard A. Snyder

Reports

An Ecological Monitoring Program (EMP) has been established at the Virginia Institute of Marine Science Eastern Shore Laboratory (VIMS ESL) for the coastal environment near the lab. The goals of the initiative are to 1) provide status and trends information to scientists who study and regulators who manage Virginia’s marine resources, 2) provide a scientific context for scientists’ research and grant proposals 3) provide pedagogical enrichment to educators for their classes, and 4) build capacity in staff expertise and training of interns and students at VIMS ESL.

The program formalizes and standardizes data collection for a long-term status and trends …

Positive Ecological Interactions And The Success Of Seagrass Restoration, Stephanie R. Valdez, Y. Stacy Zhang, Tjisse Van Der Heide, Mathew A. Vanderklift, Flavia Tarquinio, R J. Orth, Brian R. Silliman

VIMS Articles

Seagrasses provide multiple ecosystem services including nursery habitat, improved water quality, coastal protection, and carbon sequestration. However, seagrasses are in crisis as global coverage is declining at an accelerating rate. With increased focus on ecological restoration as a conservation strategy, methods that enhance restoration success need to be explored. Decades of work in coastal plant ecosystems, including seagrasses, has shown that positive species relationships and feedbacks are critical for ecosystem stability, expansion, and recovery from disturbance. We reviewed the restoration literature on seagrasses and found few studies have tested for the beneficial effects of including positive species interactions in seagrass …

Monitoring The Abundance Of American Shad And River Herring In Virginia's Rivers - 2019 Annual Report, Eric J. Hilton, Robert Latour, Patrick E. Mcgrath, Brian Watkins, Ashleigh Magee

Reports

This report describes the results of the twenty-second year of a continuing study to estimate the relative abundance and assess the status of American shad (Alosa sapidissima) stocks in Virginia by monitoring the spawning runs in the James, York and Rappahannock rivers in spring 2019, evaluating hatchery programs, and contributing to coast-wide assessments (ASMFC 2007). We also report on two fishery-independent monitoring programs using anchor gillnets in the Rappahannock River (year 2) and the Chickahominy River (year 5; a major tributary of the James River), to determine relative abundance and stock structure for the adult spawning run of river herring …

Effects Of Acidification And Salinity On Callinectes Sapidus, Mercenaria Mercenaria, And Their Interactions, Katherine Sara Longmire

Dissertations, Theses, and Masters Projects

Ocean acidification (OA) coupled with other stressors, will be detrimental at the species and ecosystem levels. Decreased carbonate ion concentrations negatively impact calcifying species, yet the combined effects of OA and other stressors are less well known, and many studies disregard species interactions. Multi-species studies involving OA and other stressors are crucial to comprehend the full threat of OA. Understanding how OA interacts with other stressors to affect species responses is necessary for future management of exploited species in an altered ecosystem. The objectives of my study were to assess: 1) the effects of long-term exposure to decreased pH and …

Bony-Tongue Fishes (Teleostei: Osteoglossomorpha) From The Eocene Nanjemoy Formation, Virginia, Eric J. Hilton, Jeffrey Carpenter

VIMS Articles

Bony-tongue fishes, Osteoglossomorpha, are distributed in North and South America, Africa, Asia, and Australia and are found on all continents except Antarctica in the fossil record. The group includes fishes such as the mooneyes (Hiodontidae), freshwater knifefishes (Notopteridae), elephantfishes (Mormyridae), and the arowanas and pirarucu (Osteoglossidae). Remains identified as belonging to the family Osteoglossidae are known from the Nanjemoy Formation of Maryland and northern Virginia and comprise isolated teeth and fragmentary jaw bones assigned to the now extinct †Brychaetus muelleri. The second author discovereda partial toothed parasphenoid among other isolated and frag-mentary vertebrate microfossils from the Fisher–Sullivan Site of the …

A Comparison Of Shorebird Habitat Use Between Living Shorelines And Natural Fringing Marshes, Robert Michael Galvin

Dissertations, Theses, and Masters Projects

We examined the use of fringing marshes by herons and shorebirds in the southern portion of Chesapeake Bay. From 13 pairs of natural fringing marshes and nearby, constructed living shoreline marshes, we completed analysis of videos recorded at discrete, 30-minute intervals (dawn, dusk, high tide, low tide) throughout the 2018 and 2019 field seasons (May through August). A total of 684 hours of recording yielded 91 individual observations of birds comprising six species. Spotted Sandpipers (Actitis macularius) were observed most frequently (25), but only at living shoreline marshes. Likewise, 15 of 16 observations of Green Herons (Butorides virescens) were at …

A Mechanistic Understanding Of Range Expansion Of Invasive Blue Catfish In The Chesapeake Bay Region, Vaskar Nepal

Dissertations, Theses, and Masters Projects

Blue catfish Ictalurus furcatus is an invasive species of great concern in coastal habitats throughout the eastern United States, inclulding the Chesapeake Bay and its tributaries. In this dissertation, I use field surveys, laboratory experiments and quantitative modeling to provide insights into several aspects of blue catfish biology at the individual level. In chapter 1, I characterize and compare patterns in growth and body condition in blue catfish populations in the James and York river subestuaries during two stages of invasion. Both the mean growth rate and mean body condition of blue catfish declined in the recent period in response …

Speciation Dynamics Of Diverging Allopolyploid Monkeyflower (Mimulus), Caroline Victoria Schlutius

Dissertations, Theses, and Masters Projects

Our understanding of speciation has been greatly improved with advances in genomic technology, but most of our knowledge of speciation is still built on research of diploid systems. Polyploids, however, are found in many lineages across the tree of life and exhibit considerably different evolutionary dynamics than diploids. Here, we investigate patterns of population structure and divergence in a system of two allopolyploid species of Mimulus (monkeyflower) that occur sympatrically in Chile: M. luteus and M. cupreus. We find that while the two species have consistent phenotypic differences across the range, they are genetically clustered into a northern and southern …

Within-Flight-Period Dynamics Driven By Phenology And Transect Quality, Not Patch Size Or Isolation, In A Specialist Butterfly, Panoquina Panoquin, Sam Mason

Dissertations, Theses, and Masters Projects

As sea levels rise, coastal salt marshes, and the organisms for which they provision, face existential threats. A first step in understanding how projected marsh loss and reconfiguration may impact obligate species is to define their contemporary distribution and temporal shifts in structure using dynamic occupancy models. While occupancy models have commonly been applied to multi-annual butterfly studies, few have investigated population dynamics within a single-season. Here, we used Bayesian dynamic use models to define within-flight-period trends in adult salt-marsh skipper (Panoquina panoquin) use and state change probability. In doing so, we developed and validated a fully-Bayesian test for closure, …

Evaluating The Impacts Of Land Use And Climate Change On The Hydrology Of Headwater Wetlands In The Coastal Plain Of Virginia, Pamela Braff

Dissertations, Theses, and Masters Projects

Located at the interface between uplands and surface water networks, headwater wetlands act as a natural filter to improve downstream water quality and play a critical role in maintaining the ecological integrity of downstream aquatic ecosystems. Vulnerable to development pressure, as well as indirect impacts from land use and climate change, the loss and alteration of headwater wetlands has been linked to the loss of biodiversity and regional water quality declines worldwide. The overall goal of this dissertation is to address some of the challenges associated with the management and conservation of headwater wetlands in the coastal plain of Virginia …

Predicting The Impacts Of Climate Change On The Sandbar Shark And Cobia, Daniel P. Crear

Dissertations, Theses, and Masters Projects

A changing climate has been identified as a major driver of changes in marine species’ distribution, phenology, and habitat selection in recent decades and is expected to continue to influence these traits. These changes are not only happening in our oceans, but within coastal habitats as well, where waters are susceptible to sudden changes in temperature and oxygen levels are influenced by nutrient inputs. These changes which will likely impact fish species that utilize these areas as nurseries, spawning habitat, or foraging grounds. In this dissertation I consider climate impacts on two important predators, the sandbar shark (Carcharhinus plumbeus) and …

The Epibiont-Host Interaction Between Zoothamnium Intermedium And Estuarine Copepods, Lucia S.L. Safi

Dissertations, Theses, and Masters Projects

Ciliates are basal eukaryotes from Phylum Ciliophora that were first described 400 years ago, but their origins date back 800 million years. Such early origins have allowed contemporary ciliates to be remarkably diverse in both their species numbers and ecological adaptations. Peritrichia, a subclass of ciliates, represents an ideal model to study ciliate diversity, as its members display complex phylogenetic relationships and can be epibionts colonizing the body surface of other organisms. Epibiotic relationships are ecologically and evolutionarily important due to the extensive adaptations in epibiont biology to the life cycles of hosts. These relationships are also important for host …