Coral reefs, found in tropical regions, are renowned for their rich biodiversity and their contributions to ecological, cultural, and economic aspects worldwide. The success of coral reefs hinges on the symbiotic partnership between corals and their dinoflagellate algae, from the family Symbiodiniaceae. The algae reside within the coral host’s gastrodermal...
Long-term, large-scale studies of meta-ecosystems provide critical information about how global change influences communities. In my dissertation, I analyzed data from studies encompassing 18 years (2006 – 2023) and over 1,000 km of coastline to investigate drivers of rocky intertidal community structure and dynamics. Specifically, I explored the roles of...
Sound is a crucial aspect of the underwater environment for fishes – various species use sound to communicate, identify predators, navigate, and many other activities needed for survival in their habitat. Disruptions and disturbances in the natural soundscape can have important impacts on all these activities and are likely to...
Chapter 2:
Aquatic macroinvertebrate communities have been shown to exhibit strong differences between erosional (riffle and run) and depositional (pool) macrohabitats of streams. A subset of these communities are aquatic insect taxa that are an important food source for riparian consumers like birds, bats, lizards, and spiders. Understanding the role...
As global atmospheric carbon emissions continue to rise, scientists and land managers are increasingly looking to natural ecosystems to sequester and store carbon to buffer the impacts of climate change. Despite their small geographic size, many coastal ecosystems such as salt marshes, seagrass meadows, and mangroves sequester large amounts of...
Non-native ecosystem engineers, which modify the structure and function of their ecosystems, are often a particularly concerning and costly group of invasive species. Such organisms may have substantial impacts on ecosystem services, or the benefits that humans derive from their ecosystems. Many factors play a role in the invasion success...
The intricate relationship between wildlife health and the quality of their environment is well established, with technological advances increasing our understanding and aiding the unraveling of underlying mechanisms. Large herbivores require forage of sufficient quality to maintain their condition to reproduce and survive, all while warding off parasites and predators...
The European green crab (Carcinus maenas) has persisted in Oregon and Washington coastal estuaries since the late 1990s. A strong year class arrived during the 1998 El Niño, but numbers decreased and remained below 1 per trap per day until the arrival of the 2015-2016 El Niño. Since then, numbers...
In 2019, a multi-cohort population of the typically estuarine burrowing shrimp Neotrypaea sp., was discovered approximately 7 miles offshore of Newport, Oregon. Morphological analysis of the offshore population, microbial sediment sequencing, and species distribution modeling was conducted with this new offshore population. In order to identify Neotrypaea sp. to the...
Daily cyclical changes of light are brought on by the axial rotation of the Earth while seasonal changes in light are caused by Earth’s tilt as it revolves around the sun. Major life history traits, such as development, which are tied to metabolic processes, have a strong link to the...
Nutrients play a large role in sustaining the symbiotic relationship between the algae and host sea anemone. The endosymbiotic algae provides the host with fixed nitrogen, sugars, and inorganic food sources, while the host provides the algae with shelter and nitrogenous waste. If the anemone does not receive the proper...
At a time when environmental conditions are rapidly changing, understanding how thermal extremes impact wildlife is imperative to fully understanding the consequences of climate change in natural ecosystems. While many organisms are currently impacted by rapidly warming and more erratic environmental conditions, identifying and investigating model species whose life histories...
The diverse community of bacteria living within and on host organisms, known as the microbiome, has an important role in maintaining host health. Dysbiosis, known as a change in the healthy community of the microbiome, has been associated with a number of diseases across host organisms and body sites including...
The rates of biological introductions and invasions are increasing, driving up the associated harms to ecosystems and economies. The spread and effects of invasive organisms depend on the specifics of the introduction, the character of the invaded ecosystem, and multiple traits of the invasive organism itself. One mechanism by which...
The European green crab (Carcinus maenas) has persisted in Oregon and Washington coastal estuaries since the late 1990s. A strong year class arrived in the Davidson Current during the 1998 El Niño, but numbers decreased and remained below 1 per trap per day until the arrival of the 2015-2016 El...
Coral reefs form vast ecosystems in tropical oceans that are hotspots for biodiversity and are economically valuable. The ecological success of coral reefs is made possible by the symbiotic relationship between corals and dinoflagellate algae from the family Symbiodiniaceae. In this symbiosis, the algae are found within host gastrodermal cells...
In the face of environmental stressors, change is imperative for species to remain in place. The nature and degree of this change is of great interest, as it sheds light into the ways in which species respond to ecological and habitat change and may continue to respond during periods of...
Most marine fishes experience high rates of mortality during their early life history stages with far reaching consequences for adult population dynamics. Within a few weeks of hatching, relatively small changes in larval growth and mortality rates can lead to orders of magnitude variability in year-class strength. Growth and survival...
Climate change presents multiple stressors that are impacting marine life. As carbon dioxide emissions continue to increase in the atmosphere, atmospheric and sea water temperatures increase. In addition, more carbon dioxide is absorbed into the oceans, reducing pH and aragonite saturation state, resulting in ocean acidification (OA). Tightly coupled with...
Salmonid fish raised in hatcheries often have lower fitness (number of returning adult offspring) than wild fish when both spawn in the wild. Body size at release from hatcheries is positively correlated with survival at sea. So one explanation for reduced fitness is that hatcheries inadvertently select for trait values...
Writing within Discipline is a pedagogical model that aims to engage students in active learning and to develop critical thinking and writing skills within the norms of a particular discipline. However, lack of faculty time for grading writing products impedes its broader implementation. Web based peer review programs have been...
The adaptive capacity of marine calcifiers to ocean acidification (OA) is a topic of great interest to evolutionary biologists and ecologists. Previous studies have provided evidence to suggest that larval resilience to high pCO2 seawater for these species is a trait with a genetic basis and variability in natural populations....
The production of novel hybrid zones is an ecologically important consequence of globally increasing rates of species introductions and invasions. Interspecific hybridization can facilitate gene flow between parent species or produce novel taxa that may alter invasion dynamics or ecosystem services. The coastal sand dunes of the U.S. Pacific Northwest...
Animals aggregate and interact in nonuniform and nonrandom patterns, which lead to group level characteristics that have important evolutionary and ecological consequences. Network analysis provides a useful conceptual framework for linking animal interactions at all scales from dyads to communities, to populations and ecosystems. Despite exciting theoretical and applied advances...
A central theme of ecology is determining factors that influence species distributions. Within aquatic ecology, species present in flowing waters are primarily influenced by the natural flow patterns of the stream (natural flow regime paradigm) while explanations of species present in standing waters are further divided by habitat type. To...
Kelps are large brown algae in the order Laminariales and are foundation species that form the basis of kelp forests. Present across a quarter of the world’s coastlines, kelp forests provide diverse services to coastal communities, as habitat for commercially and culturally important species, as a food source for humans...
Anthropogenic climate change is threatening biodiversity as I currently understand it. There is now a large body of work highlighting species responses, globally, to this threat. Importantly, responses at the species level emerge from responses at lower levels of biological organization (individuals and populations) across a species’ geographic range. For...
How the direct and indirect effects of species interactions cascade to affect community structure, functioning, and stability is a fundamental question in ecology. In temperate kelp forests, species interactions, in conjunction with environmental processes, produce rich spatiotemporal dynamics.
Arguably the most dramatic of these are abrupt shifts in community state,...
Sandy beaches and dunes cover approximately one-third of the world’s ice-free coastlines and provide ecosystem services including coastal protection, recreation, wildlife habitat, and carbon sequestration. These dynamic interface habitats are variably shaped by wind, waves, sedimentary processes, and vegetation feedbacks. Positive biophysical feedbacks lead to the formation of vegetated coastal...
Evolve & Resequence (E&R) experiments subject laboratory populations to environments controlled by investigators, who then document the phenotypic and genomic changes that take place over many generations. These experiments provide powerful tools for testing of a wide variety of evolutionary questions, especially questions about the nature of adaptive traits. While...
Biologists have long been fascinated with reproductive traits, in part because they are frequently exaggerated or showy, and they commonly vary among closely related species. Exaggerated sexual traits, in particular, have been the focus of intense empirical and theoretical research, but most of this work has focused on traits involved...
For many historical and contemporary experimental studies in marine biology, seawater carbonate chemistry remains a ghost factor, an uncontrolled, unmeasured, and often dynamic variable affecting experimental organisms or the treatments to which investigators subject them. We highlight how environmental variability, such as seasonal upwelling and biological respiration, drive variation in...
Climate change and other anthropogenic impacts are threatening the existence of millions of species around the globe. On western continental boundaries, the large-scale secondary process of upwelling, which brings low pH, deoxygenated, high nutrient seawater to the surface, is compounded by climate change, that together could drive some species to...
European green crab, Carcinus maenas, trapped and collected in coastal Oregon and Washington coastal estuaries during the 2019. Data for individual crabs include: estuary, site, date of collection, sex, carapace width, weight, molt stage (color of abdomen), missing limbs, estimated year class, method of collection, and name of collector.
This...
Species declines and extinctions have been recorded across taxa as evidence of an ongoing global biodiversity crisis. Amphibians are at the forefront of these declines with nearly one third of amphibian species estimated to be at risk of extinction. While many factors contribute to population declines and extinctions, the role...
Most benthic marine fishes have a biphasic life cycle with a dispersive pelagic larval stage that spends weeks to months in the plankton before metamorphosing into juveniles and settling to benthic habitats. The magnitude of mortality during the early life stages of marine fishes typically drives variability in year-class strength....
Understanding and predicting how regional to global scale processes affect macroalgal populations and communities requires elucidating the mechanisms underlying observed patterns. This dissertation identifies some of the underlying mechanisms that produce complex multi-scale responses of macroalgae across space and time by delineating the role of key local environmental drivers and...
The United States of America and the world are faced with three massive intertwining challenges at this time: COVID-19, racial inequity, and climate change. As a species, humans must come together and collectively address these challenges to preserve our humanity and make our world a more just and livable place...
Interest is expanding for the potential role of estuaries, particularly seagrass and salt marsh habitats, to sequester carbon, mitigate ocean acidification, and support abundant fisheries. The important functions of estuaries are part of a broader set of ecosystem services, or benefits to humans, which are regulated by ocean and watershed...
The rocky shores of the US West Coast are home to diverse ecological communities made up of species that are uniquely adapted for survival at the harsh boundary between land and sea. Even so, physical or environmental stressors regularly kill swaths of animals on the rocks. This is called disturbance....
Reef building corals are the foundation of an entire ecosystem, but they are threatened primarily by rising ocean temperatures due to climate change. Corals depend on a thermally sensitive symbiosis with intracellular dinoflagellates. As oceans warm, this symbiosis is disrupted and results in coral mortality, declining populations and degraded reefs....
Understanding of gene flow, connectivity, and diversity is critical to predict the stability of key marine species. The Oregon coast of the U.S.A. shows fine-scale levels of geographic variation in environmental stressors such as temperature, pH, and oxygen levels, prompting questions about the potential for local adaptation. In this thesis,...
Fluctuations and spatial heterogeneity of habitat and resources is thought to underlie niche variation in animal populations, with intraspecific differences serving to produce or maintain population-, community-, or ecosystem-level patterns. Individual diet variation, defined as individual variation in food resource use within a population that is consistent over time, is...
The last century has experienced a marked increase in emerging infectious disease (EID, hereafter) – jeopardizing human, domestic animal, and wildlife health. EIDs are commonly associated with spillover from one host species into a novel host species, with many destructive diseases, for both livestock and wildlife, emerging at the wildlife-livestock...
All mammals host communities of commensal microbes in and on their bodies. Recent technological advances, combined with experimental studies in laboratory animals, are beginning to reveal the ubiquitous links between the gut microbiome and host disease, metabolism, immunity, and numerous other host functions. A new challenge of microbiome research is...
Plant-parasitic nematodes cause more than US $100 billion in annual agriculture loss worldwide. Thorough knowledge of their genetic diversity, and interactions with endosymbionts and environment have the potential to provide valuable insights into the basic biology of these animals, and assist future efforts aimed at management of these plant parasites....
Anthropogenic CO₂ emissions are shifting the global climate equilibrium, causing widespread losses in biodiversity. Anthozoan cnidarians are some of the species most vulnerable to environmental change. Environmental stress causes corals and sea anemones to expel their endosymbiotic algae, which constitute a primary source of nutrition for some Anthozoa. Carbonic anhydrase...
In this dissertation, I investigate the evolution and genomes of carabid beetles, a worldwide family of over 38,000 species. I focus on two species-rich groups, the tribes Chlaeniini and Bembidiini, both of which are primarily found on the shores of bodies of water. The former are distinctive for their defensive...
Survival of marine fishes during their early life history stage is tightly related to prey availability and predation pressure. Yet, our understanding of how individual larvae to entire assemblages are constrained by these factors is limited. We integrated biological sampling of larval fishes with fine-scale in situ imaging to relate...
The European green crab (Carcinus maenas) has persisted in Oregon and Washington coastal estuaries since the late 1990s. After the arrival of a strong year class in 1998, significant recruitment to the populations occurred only in 2003, 2005, 2006, 2010, 2015, 2016, 2017, 2018 and 2019. Warm winter water temperatures,...