Life Sciences Commons^™

Seasonal Growth, Movement, And Survival Of Juvenile Coho Salmon (Oncorhynchus Kisutch) Utilizing Restored Rearing Habitat, Monica S. Tonty

Cal Poly Humboldt theses and projects

The Scott River supports the most robust population of threatened Coho Salmon Oncorhynchus kisutch remaining in the Klamath River basin. Even in the Scott River, low quality and restricted extent of juvenile rearing habitat limits the Coho Salmon population to a small fraction of historic abundance. To support persistence and recovery of Scott River Coho Salmon, the Scott River Watershed Council (SRWC) has constructed a portfolio of restoration projects to improve juvenile rearing habitat, including beaver dam analogs (BDAs). The Scott River BDAs were the first implemented anywhere in California. This study compares juvenile Coho Salmon responses associated with production …

Benthic Community Dynamics And Stony Coral Demographics In Florida In Relation To Acute Disturbances And Chronic Pressures, Nicholas P. Jones

All HCAS Student Capstones, Theses, and Dissertations

The persistence of coral reef communities is threatened by a suite of pressures operating at varying spatial and temporal scales. In general, acute disturbances (short term stochastic events such as marine heatwaves or hurricanes) and chronic pressures, such as ocean warming, have caused the most significant changes to stony coral assemblages (order Scleractinia) and continue to impair recovery potential. Additionally, many coral reefs are subject to local chronic anthropogenic pressures resulting in poor water quality or sedimentation, which further impact stony corals and shape benthic community structure, particularly near urbanized coastlines. For the viability of communities on coral reefs, a …

Largemouth Bass In The Upper Mississippi River: An Evaluation Of Management Strategies And Understanding Potential Factors Influencing Dynamic Rate Functions, Kylie Beth Sterling

MSU Graduate Theses

The Upper Mississippi River (UMR) supports ecologically and economically important commercial and recreational fisheries. One recreational fishery in the UMR is the Largemouth Bass fishery. Recreational fisheries can be effectively managed using information on population dynamics, though little is known about Largemouth Bass population dynamics in large river ecosystems. Therefore, the objectives of this study were to 1) evaluate recruitment, growth, and mortality of three Largemouth Bass populations in the UMR, specifically within Pools 4, 8, and 13, and 2) to use those estimates of recruitment, growth and mortality to inform exploitation models to evaluate best management practices for each …

Smallmouth Bass Feeding Dynamics And Growth In Headwater Streams Of The Interior Highlands, Brandon C. Plunkett

ATU Theses and Dissertations 2021 - Present

Smallmouth Bass have been extensively studied, but knowledge of the effects of temperature and hydrologic regime on populations in the Interior Highlands of Arkansas remains lacking. In 2018, I monitored diet characteristics of Smallmouth Bass, located in streams prone to dryness and representing a range of water temperatures, and presence of potential competitors. Diet characteristics of Smallmouth Bass, Green Sunfish, and Creek Chub were studied in the Boston Mountains ecoregion of Arkansas during the summer of 2018. In 2019, I expanded the scope of the project to search for relationships between Smallmouth Bass growth and hydrologic regime. My objectives were …

Effects Of Large Wood Restoration On Coho Salmon In A Northern California Watershed: A Before-After-Control-Impact Experiment, Natalie B. Okun

Cal Poly Humboldt theses and projects

Substantial time, money, and effort are invested in river and stream restoration projects to aid in the recovery of imperiled salmonid populations, but there is little evidence that these efforts have had lasting positive impacts on juvenile fish growth and survival. To assess the effectiveness of large woody debris (LWD) restoration, which is one of the most common restoration practices, I evaluated the growth and survival response of endangered Central California Coast coho salmon (Oncorhynchus kisutch) in a paired watershed before-after impact-control (BACI) study. To determine if LWD supplementation influenced coho salmon growth and survival, two neighboring, similar …

Pre-Juvenile Naked Goby (Gobiosoma Bosc) Age And Growth, Annamaria Deitz, Juliana Harding

Honors Theses

Due to the abundance of larval naked gobies, Gobiosoma bosc, within the estuarine ichthyoplankton, it is important to understand their age and growth. Naked gobies are a largely distributed, both geographically and within an estuary, small, benthic fish species. There are 3 pairs of otoliths, calcium carbonate structures within the ear canal, that detect vibrations and record the age of the fish, both daily and annually. Using laboratory-reared gobies of a known age (Tremont et al. 2015), daily signatures on the sagittal otoliths were first validated to be daily, then a growth curve for the wild caught larvae was …

A Snapshot Of The Age, Growth, And Reproductive Status Of Gray Triggerfish (Balistes Capriscus, Gmelin 1789) On Three Artificial Reefs In The Northwest Gulf Of Mexico, Adam M. Lee

Theses and Dissertations

Age, growth, and reproductive status of gray triggerfish (Balistes capriscus) were identified from 2015-2016 on artificial reefs in the northwest Gulf of Mexico. Individuals ranged from 232-432 mm fork length with and a mean fork length of 319 mm. Individuals from age 0.2 to 5.2 yrs were observed with a weight to length relationship of Wg = 1.1 x -104 x FL2.7 (r2 = 0.94, n = 112), where FL = fork length (mm) and Wg = weight (g). A von Bertalanffy growth equation of Lt = 326(1 - e - 0.9 (t + 1.71)) was calculated irrespective …

Growth And Survival Of Wild And Head-Started Blanding’S Turtles (Emydoidea Blandingii), Callie Klatt Golba

Graduate Research Theses & Dissertations

Blanding’s Turtles (IUCN Endangered) are long-lived reptiles with delayed sexual maturity. Anthropogenic landscape changes have increased threats to juvenile turtles, resulting in unnaturally low recruitment. Head-starting has become a popular conservation strategy that aims to increase juvenile recruitment by avoiding the increased predation of the vulnerable nest and hatchling age-class. However, there is still debate about whether or not it is an effective management tool. Assessments of head-starting are becoming more prevalent, but long-term studies are needed to critically evaluate the success of such interventions. In particular, information is needed on how head-starts fare compared to wild-born turtles. The Lake …

Indirect Effects Of Ocean Warming And Acidification On The Realized Recruitment Of Agaricia Agaricites, Allan Anderson

HCNSO Student Theses and Dissertations

Over the past few decades, coral cover has declined worldwide due to overfishing, disease, and storms, and these effects have been exacerbated by ocean warming and acidification. Corals are extremely susceptible to these changes because they are already living close to their thermal and aragonite saturation thresholds. Ocean warming and acidification (OAW) may also impact coral survival and growth by impacting their settlement cues. Coral larvae use crustose coralline algae (CCA) and their associated biofilms as cues for settlement, i.e., habitat selection. Settlement cues can also be negatively affected by increased water temperature and acidity. It was hypothesized that the …

Optimization Of Light Irradiance During The Early Life Of Sexually-Produced Porites Astreoides And Agaricia Agaricites Recruits, Nicholas J. Mcmahon

HCNSO Student Theses and Dissertations

Current solutions of coral restoration rely mainly on fragmentation. Though a reliable technique, this asexual form of reproduction does not benefit the genetic diversity of the coral reef. With many global and local stressors threatening corals’ existence, the resiliency of corals to future ocean conditions depends highly on sexual reproduction to produce new genotypes. New technology allows coral spawning/larval release, larval settlement and rearing to be carried out in an aquarium system. Many of the techniques necessary to maintain coral recruits are well-established, however the effects of light intensity remain to be studied for these early life stages. Newly …

Analysis Of Temperature And Salinity Effects On Growth And Mortality Of Oysters (Crassostrea Virginica) In Louisiana, Troy Sehlinger

University of New Orleans Theses and Dissertations

Salinity (S) and temperature (T) control every facet of the eastern oyster (Crassostrea virginica) life cycle, principally reproduction, development, growth, and mortality. Previous studies conducted in in the Breton Sound (BR) and Barataria (BA) estuaries have reported differences in growth and mortality rates between the basins. In the present study, environmental conditions were synchronized to compare growth and mortality rates between basins at similar combinations of T and S. Results indicate that when T and S are the same (synchronized), seasonal oyster growth and mortality rates differ between BR and BA. Seasonal analyses revealed that as salinities increased …

Effects Of Ocean Warming And Acidification On Fertilization Success And Early Larval Development In The Green Sea Urchin, Lytechinus Variegatus, Brittney L. Lenz

HCNSO Student Theses and Dissertations

Climate change is predicted to affect the larval stages of many marine organisms. Ocean warming can reduce larval survival and hasten larval development, whereas ocean acidification can delay larval development. Ocean acidification is especially concerning for marine organisms that develop and grow calcified shells or skeletons in an environment undersaturated with calcium carbonate minerals. This study assessed the effects of ocean warming and acidification on the fertilization and larval development of the green sea urchin, Lytechinus variegatus, a tropical species common in Florida and the Caribbean. After spawning, gametes were fertilized and embryos/larvae were reared at: 1) 28°C and …

Transgenerational Effects Of Thermal Stress: Impacts On And Beyond Coral Reproduction, Alyson Kuba

HCNSO Student Theses and Dissertations

Ocean warming causes stress to corals and records reveal that periods of thermal stress are increasing in frequency and severity. Previous studies show that thermal stress negatively impacts the reproductive output of corals. However, the transgenerational impacts of coral bleaching have never been quantified. As a consequence, it is unclear how ocean warming may alter population dynamics due to effects on reproduction and recruitment. This study quantified the transgenerational impacts of thermal stress in Montastraea cavernosa. To assess transgenerational effects of temperature stress during gametogenesis, colonies were exposed to elevated temperature for two weeks four months prior to spawning, …

Assessment Of A Hatchery Based Rainbow Smelt Supplementation Effort, Andrew O'Malley

Electronic Theses and Dissertations

Rainbow Smelt (Osmerus mordax) are an important fish distributed throughout northeastern North America with both anadromous and landlocked populations. Abundance, size at age, and maximum size vary widely among populations and life histories. In order to compare anadromous and landlocked populations, we collected spawning adults in 2014 from four anadromous and three landlocked populations. Scales and otoliths from the anadromous fish were examined and compared for estimates of bias and precision in ageing. Analysis of both scales and otoliths provided age estimates that were acceptable, but estimates from scales were more precise and had less bias. Otoliths were …

Natural Vs. Anthropogenic Sedimentation: Does Reducing A Local Stressor Increase Coral Resilience To Climate Change?, Francesca Fourney

HCNSO Student Theses and Dissertations

Corals face serious worldwide population declines due to global climate change in combination with direct anthropogenic impacts. Global climate change is difficult to manage locally, but policy makers can regulate the magnitude of local stressors affecting reefs. The objective of this experiment is to investigate if reducing sedimentation will enable reef corals to better endure global climate change. It has been shown that some coral species can handle climate change stress when provided with additional energy resources. Here I tested if the capacity of corals to cope with climate change can be improved when their ability to feed and photosynthesize …

"Mining" For A Reference Condition In Southern West Virginia Streams, Matthew Rouch

Theses and Dissertations

Quarterly samples were used to estimate assemblage-level (all species combined) fish production within three minimally-impacted, southern West Virginia streams. The total annual fish production estimate was highest in Slaunch Fork (37.52 kg∙ha^-1∙y^-1), a tributary of the Tug Fork River, and lowest in Cabin Creek (10.59 kg∙ha^-1∙y^-1), a Guyandotte River tributary. Creek Chub Semotilus atromaculatus, Mottled Sculpin Cottus bairdii and Blacknose Dace Rhinicthys atratulus were the most abundant species among sites, accounting for >90% of all sampled individuals. Reference condition criteria were also selected and metrics calculated for each of the three …

Understanding Basin Specific Life History Characteristics Of Lake Mead Quagga Mussels (Dreissena Bugensis) And A Potential Treatment Using Uv Radiation In Laboratory Studies, Melissa Thaw

UNLV Theses, Dissertations, Professional Papers, and Capstones

The quagga mussel (Dreissena bugensis) is an aquatic invasive species that is spreading throughout Lake Mead and other western waterways. Unlike their native waters in Eurasia, Lake Mead exhibits year round warm temperatures, high calcium levels and a lack of natural predators, all of which are very favorable conditions for their growth and spread. Dreissena bugensis reproduce and colonize hard surfaces rapidly, where they filter large amounts of water. They disrupt the aquatic food chain and interfere with infrastructure that is exposed to lake water. There is an urgent need to understand Dreissena bugensis life history characteristics within this new …

Limb Regeneration After Multiple Autotomy And Coxae Removal In The Blue Crab Callinectes Sapidus, Jennifer Ambler

OES Theses and Dissertations

This study investigated limb regeneration in the juvenile blue crab, Callinectes sapidus, specifically the role of the coxa and pedal nerve innervation of the regenerative limb bud over time. The coxa is a leg segment that has been defined as the source of positional, cellular, and neuronal information needed for limb regeneration in brachyuran crabs. This study indicates that removal of coxae under regenerative and non-regenerative conditions did not deter limb regeneration. The coxa is not the exclusive location of limb regenerative information since limbs re-grew with normal positional and functional arrangement in 86% of crabs showing regeneration at removal …

The Growth And Bioenergetics Of Callinectes Sapidus Larvae And The Effects Of Diet Quality On Larval Physiology, James J. Pletl

OES Theses and Dissertations

Food quality, especially ω3 polyunsaturated fatty acids (PUFA), can affect the physiology and metabolic efficiency of larvae of the blue crab, Callinectes sapidus. These affects may correlate with success in development and juvenile recruitment.

Larvae were exposed to two diets differing quantitatively in ω3 PUFA and respiration, excretion, growth, and feeding rates were measured for each larval stage and the megalopal stage. The energy partitioned to molts and specific dynamic action was also measured. T

he ω3 PUFA enriched diet resulted in a lower respiration rate when compared to the unsupplemented diet, but there was little differences in excretion …

The Effect Of Crowding On Growth Of The Cichlid Fish, Oreochromis Mossambicus, Bonnie A. Barrows

OES Theses and Dissertations

It has been reported that the Java tilapia, Oreochromis mossambicus, displays hypersensitivity to a substance it produces when biomass levels in a flow-through culture system exceed 20 g/1, resulting in reduced growth and high mortality. Experiments on the growth of this species in small tanks were conducted in order to determine whether O. mossambicus produces a growth-inhibiting compound under crowded conditions. This species was successfully maintained at biomass levels of 38 g/1 and 57 g/1 with a total mortality of only 4.5%.

The Java tilapia can grow rapidly in small aquaria, as indicated by the data taken during Experiment …