Pacific lamprey (Entosphenus tridentatus) is an endemic species to coastal watersheds along the Pacific Rim in North America and Asia. The species' geographic distribution is retracting and has not been mapped precisely, and the ability for the species to provide ecosystem services, such as water filtration, for supporting watershed management has not been tested. The San Luis Obispo Creek watershed, California, USA is at the southern end of Pacific lamprey’s retracting distribution, and the San Luis Obispo watershed is impacted by degraded water quality, making investigation of Pacific lamprey in the San Luis Obispo Creek watershed of direct local conservation importance. This thesis is presented as two manuscripts formatted for submission to scientific journals. The first manuscript features a study that estimates Pacific lamprey presence/absence throughout the San Luis Obispo Creek watershed using Environmental DNA. We compare our estimate to previous estimates of Pacific lamprey population distribution using established eFishing and redd survey methods. We found our estimate of distribution based on Environmental DNA to match the previous estimates throughout San Luis Obispo Creek, as well as indicate a location with Pacific lamprey presence that was previously unsurveyed. In this manuscript, we also discuss advantages and disadvantages to using Environmental DNA as a cost-effective and non-invasive method to survey Pacific lamprey in the wild. The second manuscript is a laboratory study focused on the larval (ammocoete) stage of Pacific lamprey. We tested the ability for an ammocoete population to reduce the concentration of harmful bacteria in water through filter-feeding. We found an increased decline of bacteria in experimental aquaria treated with ammocoetes than in control tanks or tanks containing non-filter feeding Pacific lamprey, indicating that ammocoetes can indeed significantly reduce bacterial loads in a contained environment. The laboratory study was conducted using water from San Luis Obispo Creek that was naturally inoculated with bacteria, generating broader applicability of the study in suggesting that Pacific lamprey have the potential to provide a water filtration ecosystem service in the wild for supporting high water quality watershed management objectives. These two studies contribute to knowledge on how to efficiently survey Pacific lamprey distribution in the wild and benefits the species may provide to ecosystems and human welfare. Collectively, they help us better understand the status and value of this often-forsaken anadromous species.

Watershed systems are experiencing rapid changes to water quality and hydrologic regimes due in part to climate-induced changes in temperature and precipitation, urbanization, and increases in aquatic invasive species. Aquatic invasive species are one of the primary threats to ecosystems, contributing to loss of biodiversity, altered hydrologic regimes, and stream degradation. Urban land use and climatic factors influence the spread of invasive species, presenting greater challenges for future invasive species management. There is a need for more research that evaluates the watershed process in connection with urban land use and climate change factors in relation to invasive species spread. This study will examine factors of climate change and land use that may be influencing the spread and occurrence of aquatic invasive plants within the Connecticut River watershed. There will be four species involved in this study: Eurasian milfoil (Myriophyllum spicatum), Variable milfoil (Myriophyllum heterophyllum), Hydrilla (Hydrilla verticillate), and the European water chestnut (Trapa natans). Hydrological conditions within the watershed will be analyzed using the SWAT model through the HAWQS interface. ArcGIS Pro will be used to combine and prepare data so that it may be utilized through MaxEnt. MaxEnt will be used to create species distribution models to estimate the probability of the presence of invasive aquatic plant species in the Connecticut river watershed.

Microplastics are widespread and abundant. Few studies have examined the diversity and abundance of microplastics in wild organisms. This study determined the microplastic quantity and types in the organic tissues of the eastern oyster Crassostrea virginica and Atlantic mud crab Panopeus herbstii from the Indian River Lagoon (IRL). This study also investigated whether location affected the microplastic abundance and variety. Organisms were collected from three sites across Mosquito Lagoon in the northern IRL. Oysters were frozen after collection. Crabs were placed in containers for 5 days before freezing. The soft organic tissue was chemically digested using hydrogen peroxide, filtered, and examined for microplastics. Water samples collected from each study site had an average of 23.1 microplastic pieces per liter and fibers were the most common type. There was a significant interaction for microplastic type and site for both oysters and crabs (p

Oyster reefs are important estuarine ecosystems that provide habitat to many species including threatened and endangered wading birds and commercially important fishes and crabs. Infaunal organisms (i.e. small, aquatic animals that burrow in the sediment) are also supported by oyster reef habitats. Infaunal organisms are critical to marine food webs and are consumed by many important species that inhabit coastal estuaries. However, over the past century 85% of shellfish reef habitats have been lost, making restoration of these areas vital. Due to their important role in coastal food webs, infauna is hypothesized to be a strong indicator of habitat productivity to document the transition from a dead to a restored and living intertidal oyster reef. Research was conducted in Mosquito Lagoon of the northern Indian River Lagoon system. Three replicate samples were collected from 12 intertidal oyster reefs (four dead, four live, four restored). Samples were collected one-week pre-restoration and one month and six months post-restoration. Infauna was counted and sorted into six taxonomic categories: polychaetes, amphipods, isopods, gastropods, bivalves, and decapods. Reef infaunal abundance increased following restoration: restored reefs became more similar to live reefs one month following restoration. Six months after restoration restored reefs were also significantly different than dead reefs. Live reefs consistently had high infaunal abundance and dead reefs consistently had low abundance, while restored reefs were intermediate. These data suggest restored reefs are more productive than their dead counterparts, with restoration showing a positive trajectory to impact numerous infaunal species and their associated food webs.

The genetic structure of juvenile green turtles (Chelonia mydas) foraging on the east coast of central Florida is not well understood, nor has it been examined over time. In the last three decades, the dramatic increase in the number of green sea turtle nests in Florida, in association with other population parameters, has led to this species being down-listed under the Endangered Species Act from “endangered” to “threatened” in the northwest Atlantic. However, it was unclear if the exponential growth in Florida nest numbers had any influence on the genetic structure of juveniles in nearby foraging aggregations. To understand this potential impact mixed-stock analysis was conducted using mitochondrial DNA fragments that were over 800 base pairs long on samples taken from juveniles captured from 2002-2005 and 2016-2018 in the central Indian River Lagoon and Trident Submarine Basin in Port Canaveral. Results indicate the sampled foraging sites are genetically distinct habitats. In both sites, recruitment from Florida nesting beaches remained low despite increases in nesting while contributions from rookeries in Costa Rica and Mexico dominated both foraging aggregations across time. Haplotype diversity and nucleotide diversity decreased at both foraging sites over time. The foraging sites shared the two most frequently occurring haplotypes, but also had haplotypes that were unique to the site or sample period. Our results highlight the need for broader sampling of rookeries and foraging aggregations to understand the impacts of nesting increases in one rookery on juvenile diversity. Future studies should include all life stages of green turtles to enhance understanding of both the census population and effective population to better inform conservation policies necessary for a continued recovery.

A fish kill was observed in a historically freshwater region of the Everglades, coinciding with a spike in salinity. Sea level rise and altered hydrology allow freshwater wetland systems to be susceptible to saltwater intrusion. Most wetlands are characterized by highly organic soils with microbial communities starved of oxygen, seeking alternative electron acceptors. Seawater contains sulfate (SO42-), which is one of the alternative electron acceptors. Provided with sufficient quantities, sulfate-reducing bacteria (SRB) outcompete other anaerobes and produce toxic hydrogen sulfide. This study asked, what combination of soil organic matter (SOM) and SO42- are needed to produce sulfide concentrations potentially lethal to freshwater fish? Soil samples were collected from two freshwater wetlands with varying SOM content and incubated in microcosms at four SO42- concentrations (0, 0.75, 4.0, and 12.0 mM Na2SO4). Sulfide concentrations produced were compared to published data on lethal sulfide toxicity levels for aquatic life. This study demonstrated that high SOM soils (89.3 ± 0.2 % moisture) incubated with SO42- concentrations > 0.75 mM, rapidly produced toxic sulfide concentrations (> 5 ppm S2-) within 24 hrs.. While many freshwater species may tolerate a salinity of 1 ppt (0.75 mM SO42-), this SO42-concentration is sufficient to support SRB and lead to toxic sulfide production. ese results support the need to restore freshwater hydrology in wetland systems, such as the Everglades, thereby protecting against the rapid ecological effects of saltwater intrusion.

The protection system in a shipboard power system plays a vital role in detecting the fault conditions, isolating the faulted zone and preventing the fault propagation into other vital sections onboard the ship. The protection system should be able to remove faults and restore the service to all the vital loads rapidly. In order to design the protection system, preliminary hardware-in-the-loop testing is done using bus differential relay hardware and a Real Time Digital Simulator (RTDS). In this thesis work, based upon the functionalities of the relay hardware the software differential relay model is designed and simulated using the RSCAD Version 2.00 software suite and RTDS. The software differential relay model developed in RSCAD was tested on a terrestrial power system and a shipboard power system test case for various fault conditions, and its functionalities are validated based upon the hardware-in-the-loop test results.

Ecology may be oonsidered as one of the vital parts of botany, since there are two ultimate facts in this science; namely, the plant and its habitat . The habitat is made up of the physical factors that control function. At Timpanogos there are so many different habitats, that the chief problem is not that of finding a problem to study, but rather that of selecting one from the many. The purpose of this paper is to point out some of the interesting features that are found in a study of Timpanogos Creek from Aspen Grove to Wildwood.

Six forest areas destroyed by fire representing different seral stages of aspen development and conifer invasion were studied to determine successional dynamics and the related livestock and big game use. Factors measured were: (a) age, basal area, density and frequency of aspen and conifer trees; (b) density and frequency of under-story species; (c) forage production for forbs, grasses, and browse, and (d) animal-days use for deer, cattle and sheep. Aspen appeared in the community the spring following the fire and conifers appeared fifteen to twenty years later. Conifers had begun to dominate aspen on an eighty-two year old stand. The density and frequency of understory species was influenced by grazing pressure, age of the cormnunity and conifer basal area. Maximum densities were reached twenty years after the fire. Forage production was influenced by the age of the community and conifer basal area. Maximum forage production was reached on the twenty-one year old burn. Animal use was influenced by the amount of forage production, conifer basal area and competitive use by other animals.

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