A great deal of research has been focused on the microbiomes of terrestrial angiosperms (flowering plants), but much less research has been performed on the microbiomes of aquatic angiosperms (Turner et al. 2013). Eelgrass beds are extremely productive ecosystems that provide habitat for many marine organisms, such as fish, shellfish,...
Humans and viral disease are inextricably intertwined. Viral disease plays an immeasurable role in human life, from the disease and economic burden associated with every facet of contending with human viral disease, to managing the consequences of viral disease in organisms important to our food supply, economy, and entertainment. The...
The lagoons spanning Alaska’s Beaufort Sea coast provide a unique habitat for arctic wildlife. These lagoons and the food webs they support face extreme seasonality with nine months of ice cover followed by a spring thaw that pulses a large amount of freshwater and nutrients into the lagoons. Bacteria link...
Phytoplankton initiate the marine carbon cycle by fixing carbon dioxide into biologically available compounds. These abundant single celled organisms mediate carbon flux from the atmosphere to the deep ocean and are the base of the marine food web, supplying new carbon to higher trophic levels. Phytoplankton are highly diverse and...
The myxozoan parasite Ceratonova shasta threatens both juvenile and adult salmonid populations in the Pacific Northwest region of the United States, causing intestine necrosis and hemorrhaging, along with high mortality in some fish strains. It induces an inflammatory tissue response in susceptible strains of fish; understanding the interactions between C....
Biotic and abiotic processes at continent-ocean interfaces cycle a disproportionate mass of carbon and nutrients relative to their global surface area, and microbial activity is a principal determinant of organic and inorganic matter flux in these transition zones. Most studies using modern high-throughput ‘omics techniques to link microorganisms with costal...
The freshwater polychaete Manayunkia speciosa was identified as an obligate host of the salmonid parasite Ceratomyxa shasta in 1997, prompting increased research on the small benthic invertebrate. Ceratomyxa shasta infection in fish can cause mortality, and presents a disease risk for both hatchery and wild salmon and trout. Ceratomyxa shasta...
Our experiments aimed to investigate responses of the marine cyanobacteria Prochlorococcus and Synechococcus to toxic arsenic species, such as arsenate, and to understand cellular mechanisms that contribute to arsenic tolerance. We used two strains of Prochlorococcus, a high-light adapted MED4 and low-light adapted MIT9313, both axenic, for cultivation experiments. For...
On coral reefs, disturbances rarely occur in isolation. Global stressors such as increasing seawater temperature often coincide with local stressors like nutrient pollution. In the face of increasing anthropogenic stress, corals can function as environmental sentinels, although little is known about how multiple stressors interact to disrupt their associated bacterial...
Vibrio bacteria are commonly found in freshwater, marine, and estuarine environments. Members of this genus can exist in commensal relationships with marine animals or as planktonic bacteria, however, they are well known for their roles as pathogens towards humans and animals. In this dissertation, I investigated aspects of host-bacteria relationships...
At a time of rapid global change, a socio-ecological system (SES) approach can provide a framework through which to quantify and communicate the risks and uncertainties of coupled human-natural systems. Islands, and tropical coral reef islands in particular, can be excellent models for SES research since they may be considered...
Coral reef ecosystems continue to be significantly altered by disease epizootics, but why some host populations remain resistant while others succumb to outbreaks remains unknown. Research across diverse animal and plant host systems has revealed that disease severity is strongly influenced by host genetics and by environmental influences on both...
Toxin production by cyanobacterial harmful algal blooms (cyanoHABs) in freshwater systems has lasting ecological and human impacts. Nutrients, light availability, hydrology, and microbial community composition impact the frequency and intensity of toxic cyanoHABs. Climate change will exacerbate toxic cyanoHABs, making real time and predictive monitoring a vital tool for managing...
Marine mammals are top predators that are essential for the health and function of our oceans. These top predators are often affected by various factors that can be detrimental to their populations. Therefore, there is a need to evaluate undetermined causes of deaths and to better understand known diseases in...
Diatoms play a major role in ocean biogeochemical cycles and are important tools in bioengineering for natural products and nanotechnology. Diatoms and other algae growing at varying resource-limited growth rates allocate carbon to different metabolic pathways to optimize growth; however, the molecular mechanisms controlling these pathway gating strategies are not...
Freshwater systems cycle carbon along a spatial and temporal biogeochemical continuum, across which ecosystem processes contribute to transformations of organic matter (OM). Various ecological constraints impact rates OM transformation and production and consumption of the energetic end of respiration, methane. Microbiological processing and complete reduction of carbon substrates to methane...
Agricultural and companion animals are integral to our way of life as they provide us with nourishment, financial resources, transportation, and companionship. However, pets, managed animals in the agricultural industry, as well as wild populations of food animals are all subject to health and mortality risks. The gut microbiome is...
The phylum Cnidaria contains three main branches: Anthozoa (corals, sea anemones) Medusozoa (jellyfish, hydra), and Endocnidozoa. This latter branch is characterized by parasitism and contains the microscopic fish-parasites Myxozoa. Myxozoa are highly simplified, consisting of only a few cell types, however they have retained the nematocyst stinging cells and complex...
Marine sediments are vast sources and reservoirs of methane, a potent greenhouse gas. Most of this methane is anaerobically oxidized by archaea before it can reach the overlying ocean, though the efficiency of this process often depends on methane fluxes and mechanisms of fluid transport. Anaerobic methanotrophic archaea, or ANME,...