Tag Archives: ocean

Is Climate Change Making Gray Whales Picky Eaters?

The Oregon Coast is known for its ruggedness and harsh weather, but also offers a prime opportunity to spot gray whales on their migratory paths. These majestic marine mammals undertake one of the largest migrations of any animal, traveling from the Arctic to Baja California to breed before heading back north along this “whale super-highway.” Despite having the mechanisms to feed in the water column, these benthic specialists prefer bottom feeding, scooping up sand from the seafloor and filtering out invertebrate prey through their baleen, likely targeting locations of high caloric content. However, along the coast of the Pacific Northwest, a behavior known as ‘prey switching’ has been observed, where gray whales feed in the water column instead of their preferred benthic prey, amphipods. Our upcoming guest, Taylor Azizeh, a first-year Ph.D. student at the Marine Mammal Institute, explores what may be driving this prey switching behavior.

Polar regions are among the top locations to be impacted by climate change, which Taylor suspects may be responsible for grey whales switching from benthic to pelagic prey. Changes in bottom water temperature and sediment grain size may result in habitats less favorable for amphipods, leading whales to seek food elsewhere. In response to warming, the distribution of other predators may shift to where they compete for the same food source, or the reduced sea ice cover could result in more productive pelagic waters. How do gray whales, these benthic specialists, adapt to changing food availability?

Gray whale populations often experience boom and bust cycles or unknown mortality events, with the most recent one currently underway. Taylor’s research on the foraging plasticity of gray whales is not only timely, but also employs a holistic approach using a combination of methods to assess the big picture. She plans to use stable isotopes to provide information on what whales are feeding on, but only when combined with GPS tags tracking movement and drone photogrammetry measuring body conditions can one understand where and why. Taylor plans to utilize this combination to ask big picture questions such as whether they’re feeding in areas of high biomass, if they return to those same areas, and how much adaptability can individual gray whales display?

At its core, Taylor’s research delves into the adaptability of gray whales. Gray whales have survived the ice ages, proving their ability to deal with harsh conditions, and Taylor hypothesizes they may be more flexible than we currently understand.

To learn more about Taylor’s passion for these charismatic animals of ecological, social, and cultural importance, the adventure which led here to grad school—from Costa Rica to Ecuador, Denmark, and London—tune in to KBVR 88.7 FM this Sunday, Nov. 3. You can listen to the episode anywhere you listen to your podcasts, including on KBVRSpotifyApple, or anywhere else!

Diving into the Unknown: Exploring the Role of Viruses in Coral Reef Health

When you think of a coral reef, what do you picture? Perhaps you imagine colorful branching structures jutting out of rock and the sea floor, with flourishing communities of fish swimming about. Or if you’ve been paying attention to news about global warming for the past decade or two, maybe you picture desolate expanses of bleached corals, their bone-like structures eerily reminiscent of a mass graveyard.

What you might not picture is a zoomed-in view of the coral ecosystem: the multitude of bacteria, fungi, viruses, and algae that occupy the intricate crevices of every coral. While corals are indeed animals in their own right, they belong to a complex symbiotic relationship with these microorganisms: the algae, which are more specifically dinoflagellates, provide energy to the coral through the process of photosynthesis. Bacteria occupying the mucus layers cycle nutrients and play a role in defense against pathogen invasion through the production of antimicrobial peptides.

One lesser-known member of this community, or the coral ‘holobiont’ as it is called, are the viruses. It’s probable that, like other members of the holobiont, they contribute to the health of the coral in some way, but this role is as of yet unclear. Our guest this week is Emily Schmeltzer, a fifth year PhD student in the Vega Thurber lab in the Department of Microbiology, and these elusive viruses are exactly what she is trying to uncover.

Emily Schmeltzer, PhD candidate in Rebecca Vega-Thurber’s lab, takes a sample of a coral

“We don’t know a ton about viruses on coral reefs,” says Schmeltzer. “ We know that some probably cause disease or mortality through infections, but we don’t really know exactly what a lot of them are doing, because marine viral ecology is such a relatively new field,” she explains.

It’s not surprising: viruses, while the most abundant and diverse entity on earth, are incredibly tiny and difficult to detect in environments where other organisms also thrive. Part of the challenge is that they have no universally conserved genes: that is, no easy way to tell the genes from viruses apart from the genes of other organisms. When studying bacteria, a gene called the 16S rRNA gene can be used as a sort of ‘name tag’ – every bacteria has this gene, whereas other organisms do not. There’s no such thing for viruses, making them difficult to study if you don’t already know what you’re looking for.

Schmeltzer is studying the viruses that live on corals and their response to climate change. To do this, her PhD research has involved a massive spatiotemporal study (spatio = across different locations, temporal = across multiple time points) looking at nearly 400 individual coral colonies of three different species over 3 years. All of these colonies are off the coast of the Moorea, a small island in French Polynesia in the South Pacific. The ultimate goal of the project is to contribute to the ongoing data collection for the Moorea Coral Reef Long Term Ecological Research project, and to characterize virus community diversity and potential function  in the health of these corals.

Studying coral reefs is a big leap for Schmeltzer, who hails from the land-locked deserts of New Mexico. She was always interested in biology, which she attributes to her dad bringing home dead scorpions to look at together when she was a child. Arthropods ultimately ended up becoming her first research subjects: as an undergraduate at the University of New Mexico, she worked in an insect and spider taxonomy lab, before pivoting to working on West Nile virus.

So how did this insect-loving desert-dweller end up studying viruses that live on corals in the ocean? To learn more about Schmeltzer’s career trajectory, her love of corals, and the challenges of viral research, tune in to Inspiration Dissemination this Sunday, April 2nd at 7 PM. Listen live at 88.7 FM or on the live stream, or catch the episode after the show wherever you get your podcasts! 

Grouper groupie: studying climate change and the Nassau grouper

During winter months, a few days after the full moon, thousands of fish make their way to the warm tropical waters off the west coast of Little Cayman, Cayman Island. Nassau Grouper are typically territorial and don’t interact often, but once per year, they gather in the same spot where they all spawn to carry on the tradition of releasing gametes, in the hopes that some of them will develop to adulthood and carry on the population.

Our guest this week is Janelle Layton, a Masters (and soon to be PhD) student in Dr. Scott Heppel’s lab in the Department of Fisheries, Wildlife, and Conservation Sciences. Janelle’s research focuses on this grouper, which is listed as near threatened under the Endangered Species Act. Overfishing has been the largest threat to Nassau Grouper populations, but another threat looms: warming waters due to climate change. This threat is what Janelle is interested in studying – how does the warming water temperature affect the growth and development of grouper larvae?

Janelle with a curious sea turtle

Each winter Janelle travels to this aggregation site in the Cayman Islands, where these large groups of grouper (grouper groups?) aggregate for a few days to reproduce. During this time, she collects thousands of fertilized Nassau Grouper eggs to take back to the lab and study. These eggs will develop in varying water temperatures for 6 days, where each day a subset of samples are preserved for future analysis.

Spawning groupers

So far, Janelle is finding that the larvae raised in higher temperatures tend to demonstrate not only an increase in mortality, but an increase in variability in mortality. What does this mean? Basically, eggs from some females are able to survive and develop under these stressful conditions better than eggs from other females – so is there a genetic component to being able to survive these temperature increases?

The answer may lie in proteins

Aside from development and mortality, Janelle is investigating this theory by measuring the expression of heat shock proteins in the fertilized eggs and larvae. Heat shock proteins are expressed in response to environmental stressors such as increased temperatures, and can be measured through RNA sequencing. The expression of these proteins might hold the key to understanding why some grouper are more likely to survive than others. Janelle’s work is a collaborative effort between Oregon State University, Scripps Institute of Oceanography, Reef Environmental Education Foundation and the Cayman Islands Department of Environment.

To learn more about Nassau Grouper, heat shock proteins, and what it’s like being a Black woman in marine science, tune into Janelle’s episode this upcoming Sunday, March 12th at 7 PM! Be sure to listen live on KBVR 88.7FM, or download the podcast if you missed it. You can also catch Janelle on TikTok or at her website.

A Gut Feeling: Examining Whale Ecology Using Number-Two Genetics

This week we have a MS (but soon to be PhD) student from the department of Fisheries and Wildlife, Charles Nye, joining us to discuss their work examining the dietary and environmental DNA of whales. So that begs the question – how exactly does an environment, or a diet, have DNA? Essentially, the DNA of many organisms can be isolated from samples of ocean water near the whales, or in the case of dietary DNA, can be taken from the whales’ fecal matter – that’s right, there’s a lot more you can get from poop than just an unpleasant smell.

Why should we care about what whales eat?

As the climate changes, so too does the composition of creatures and plants in the oceans. Examining environmental DNA gives Charles information on the nearby ecological community – which in turn gives information about what is available for the whale to eat plus what other creatures they may be in resource competition with. He is working to identify the various environmental DNA present to assist with conservation efforts for the right whale near Cape Cod – a whale that they hold as dear to their hearts on the East Coast as the folks of Depoe Bay hold the grey whale to theirs.

By digging into the whale poop to extract dietary DNA, Charles can look into how the whales’ diets shift over seasonal and yearly intervals – and he is doing precisely that with the West Coast grey whales. These dietary shifts may be important for conservation purposes, and may also be applied to studying behavior. For example, by looking at whether or not there are sex differences in diet and asking the ever-important question: do whales also experience bizarre pregnancy cravings?

two people underwater in scuba gear. Some tall kelp in the background. One person is holding a light which emits a beam into the water.
Scuba diving underwater.

How does someone even get to study whales?

Like many careers, it starts with an identity crisis. Charles originally thought they’d go into scientific illustration, but quickly realized that they didn’t want to turn a hobby he enjoyed into a job with deadlines and dread. A fortunate conversation with his ecology professor during undergrad inspired him to join a research lab studying intertidal species’ genetics – and eventually become a technician at the Monterey Bay Aquarium Research Institute. 

After a while, simply doing the experiments was not enough and they wanted to be able to ask his own questions like “does all the algae found in a gray whale’s stomach indicate they may actually be omnivores, unlike their carnivorous whale peers?” (mmm, shrimp).

Turns out, in order to study whales all you have to do is start small – tiny turban snail small. 

Image of Charles working in the lab and using a micropipette. They are wearing a lab coat and white rubber gloves. He is holding a small tube into which the tip of the micropette is inserted.
Working in the lab.

Excited for more whale tales? Us too. Be sure to listen live on Sunday, February 5th at 7PM on 88.7FM, or download the podcast if you missed it. Want to stay up to date with the world of whales and art? Follow Charles @thepaintpaddock on Twitter/Instagram for his art or @cnyescienceguy on Twitter for his marine biology musings. 

The Puzzle of Puffy Snout

Puffy snout syndrome: though it has a cute-sounding name, this debilitating condition causes masses on the face of Scombridae fish (a group of fish that includes mackerel and tuna.) Fish afflicted with puffy snout syndrome (PSS) develop excessive collagenous tumor-like growths around the eyes, snout, and mouth. This ultimately leads to visual impairment, difficulty feeding, and eventual death. PSS is surprisingly confined to just fish raised in captivity – those in aquaculture farms or aquariums, for example. Unfortunately, when PSS is identified in aquaculture, the only option is to cull the entire tank — no treatments or cures currently exist.

Left: a mackerel with puffy snout syndrome. Collagenous growths cover the snout and eye. Right: a healthy mackerel. Photos Emily Miller

PSS was first identified in the 1950s, in a fish research center in Honolulu, Hawaii. Since then, there have only been 9 publications in the scientific literature documenting the condition and possible causes, although the fish community has come to the conclusion that PSS is likely a transmittable condition with an infectious agent as the cause. But despite this conclusion, there’s been no success so far in identifying such a cause – tests for parasites, bacterial growth, and viruses have come up empty-handed. That was until a 2021 paper, using high-resolution electron microscopy, found evidence of viral particles in facial tissues taken from Pacific mackerel. Suddenly, there was a lead: could PSS be caused by a virus that we just don’t have a test for yet?

Electron microscopy images showing viral-like particles (red arrows) in facial tissue from Pacific mackerel (Miller et al 2022).

Putting Together the Pieces

To investigate this hypothesis, this week’s guest Savanah Leidholt (a co-author of the 2021 microscopy study) is using an approach for viral detection known as metatranscriptomics. Leidholt, a fourth year PhD candidate in the Microbiology department, sees this complex approach as a sort of puzzle: “Your sample of RNA has, say, 10 giant jigsaw puzzles in it. But the individual puzzles might not be complete, and the pieces might fit into multiple places, so your job is to reassemble the pieces into the puzzles in a way that gives you a better picture of your story.”

Savanah Leidholt, PhD candidate in Rebecca Vega-Thurber’s lab, is looking for evidence of viruses in the tissues of fish with puffy snout syndrome.

RNA, or ribonucleic acid, is a nucleic acid similar to DNA found in all living organisms, But where DNA is like a blueprint – providing the code that makes you, you; RNA is more like the assembly manual. When a gene is expressed (meaning the corresponding protein is manufactured), the double-stranded DNA is unwound and the information is transcribed into a molecule called messenger RNA. This single-stranded mRNA is now a copy of the gene that can be translated into protein. The process of writing an mRNA copy of the DNA blueprint is called transcription, and these mRNA molecules are the target of this metatranscriptomics approach, with the prefix “meta” meaning all of the RNA in a sample (both the fish RNA and the potential viral RNA, in this case) and the suffix “omics” just referring to the fact that this approach happens on a large scale (ALL of the RNA, not just a single gene, is sequenced here!) When mRNA is sequenced in this manner, the researchers can then conclude that the gene it corresponds to was being expressed in the fish at the time the sample was collected.

The process of transcription: making messenger RNA from DNA. Image from Nature Education.

So far, Leidholt has identified some specific genes in fish that tend to be much more abundant in fish from captive settings versus those found in the wild. Could these genes be related to why PSS is only seen in fish in captivity? It’s likely – the genes identified are immune markers, and the upregulation of immune markers is well-known to be associated with chronic stress. Think about a college student during finals week – stress is high after a long semester, maybe they’ve been studying until late in the night and not eating or sleeping well, consuming more alcohol than is recommended. And then suddenly, on the day of the test, they’re stuck in bed with the flu or a cold. The same thing can happen to fish (well, maybe not the part where they take a test!,) especially in captivity – Pacific mackerel, tuna, and other scombrid species susceptible to PSS are fairly large, sometimes swimming hundreds of miles in a single day in the ocean. But in captivity, they are often in very small tanks, constantly swimming in constrained circles. They’re not exposed to the same diversity of other fish, plankton, prey, and landscape as they would be in the wild. “Captivity is a great place to be if you’re a pathogen, but not great if you’re a fish”, says Leidholt.

The results of Leidholt’s study are an exciting step forward in the field of PSS research, as one of the biggest challenges currently facing aquaculture farms and aquariums is that there is no way to screen for PSS in healthy fish before symptoms begin to show. Finding these marker genes that appear in fish that could later on develop PSS means that in the future a test could be developed. If vulnerable fish could be identified and removed from the population before they begin to show symptoms and spread the condition, then it would mean fish farmers no longer have to cull the entire tank when PSS is noticed.

The elusive virus

One of the challenges that remains is going beyond the identification of genes in the fish and beginning to identify viruses in the samples. Viruses, which are small entities made up of a DNA or RNA core and a protective protein coating, are thought to be the most abundant biological entities on the planet Earth – and the smallest in terms of size. They usually get a bit of a bad reputation due to their association with diseases in humans and other animals, but there are also viruses that play important positive roles in their ecosystems – bacteriophages, for example, are viruses that infect bacteria. In humans, bacteriophages can attack and invade pathogenic or antibiotic-resistance bacteria like E. coli or S. aureus (for more information on phages and how they are actually studied as a potential therapy for infections, check out this November 2021 interview with Miriam Lipton!) Across the entire planet there are estimated to be between 10^7 to 10^9 distinct viral species – that’s between 10 million and 10 billion different species. And fish are thought to host more viruses than any other vertebrate species. Because of technological advancements, these viral species have only really been identified very recently, and identification still poses a significant challenge.

As a group, viruses are very diverse, so one of the challenges is finding a reliable way to identify them in a given sample. For bacteria, researchers can use a marker gene called the 16S rRNA gene – this gene is found in every single bacterial cell, making it universal, but it also has a region of variability. This region of variability allows for identification of different strains of bacteria. “Nothing like 16S exists for viruses,” Leidholt says. “Intense sequencing methods have to be used to capture them in a given sample.” The metatranscriptomic methods that Leidholt is using should allow her to capture elusive viruses by taking a scorched earth approach – targeting and sequencing any little bit of RNA in the sample at all, and trying to match up that RNA to a virus. 

To learn more about Savanah’s research on puffy snout syndrome, her journey to Oregon State, and the amazing outreach she’s doing with high school students in the Microbiology Department, tune in to Inspiration Dissemination on Sunday, November 20th at 7 PM Pacific!

Schmitty Thompson wears glasses and a sweater, and smiles at the camera while standing in front of a vast field.

What ice sheets can teach us about ancient ocean shorelines

Around 80,000 years ago, the Earth was in the middle of the late Pleistocene era, and much of Canada and the northern part of the United States was blanketed in ice. The massive Laurentide Ice Sheet covered millions of square miles, and in some places, up to 2 miles thick. Over vast timescales this ice sheet advanced its way across the continent slowly, gouging out what we now know as the Great Lakes, carving the valleys, depositing glacial tills, and transforming the surface geology of much of the southern part of Canada and northern US. Further west, the Cordilleran ice sheet stretched across what is now Alaska, British Columbia, and the northern parts of the Western US, compressing the ground under its massive weight. As these ice sheets depressed the land beneath them, the Earth’s crust bulged outwards, and as the planet warmed and the ice sheets began to melt, the pressure was released, returning the crust underneath to its previous shape. As this happened, ocean water flowed away, resulting in lower sea levels locally, but higher levels across the other side of the planet.

The effects of massive bodies of ice forming, moving, and melting are far from negligible in their impact on the overall geology of the region, the sea level throughout history, and the patterns of a changing climate. Though there are only two ice sheets on the planet today, deducing the ancient patterns and dynamics of ice sheets can help researchers fill the geological record and even make predictions about what the planet might look like in the future. Our guest on Inspiration Dissemination this week is PhD candidate and researcher Schmitty Thompson, of the Department of Geology in CEOAS. Thompson is ultimately trying to answer questions about ice distribution, sea levels, and other unknown parameters that the geologic record is missing during two different ice age warming periods. Their research is very interdisciplinary – Thompson has degrees in both math and geology, and also uses a lot of data science, computer science, and physics in their work. They are using computer modeling to figure out just what the shorelines looked like during this time period around 80,000 years ago. 

Schmitty Thompson, fourth year PhD candidate with Jessica Creveling in the Geology Department.

“I use models because the geologic record is pretty incomplete – the further back you go, the less complete it is. So by matching my models to the existing data, we can then infer more information about what the shoreline was like,” they explain. To do this accurately, Thompson feeds the model what the ice sheets looked like over the course of around 250,000 years. They also need to incorporate other inputs to the model to get an accurate picture – variables such as the composition of the interior of the Earth, the physics of Earth’s interior, and even the ice sheets’ own gravitational pull (ice sheets are so massive they exert a gravitational pull on the water around them!)

Using math to learn about ice

The first equation to describe global changes in sea level was published in 1976, with refining throughout the 90s and early 2000s. Thompson’s model builds on these equations in two versions: one which can run in about 10 minutes on their laptop, and another which can take multiple weeks and must run on a supercomputer. The quicker version uses spherical harmonics as the basis function for the pseudospectral formulation, which is basically a complex function that does math and incorporates coefficient representations of the earth’s radius, meridional wave numbers, variation across north/south and east/west, and a few other variables. The short of it is that it can perform these calculations across a 250k time span relatively quickly, but it makes assumptions about the homogeneity of the earth’s crust and mantle viscosity. Think of it like a gumball: a giant, magma-filled gumball with a smooth outer surface and even layers. So while this method is fast, the assumptions that it makes means the output data is limited in its usefulness. When Thompson needs a more accurate picture, they turn to collaborators who are able to run the models on a supercomputer, and then they work with the model’s outputs.

While the model is useful for filling in gaps in the historical record, Thompson also points out that it has uses in predicting what the future will look like in the context of a changing climate. After testing out these models and seeing how sensitive they are, they could be used by researchers looking at much smaller time scales and more sensitive constraints for current and future predictions. “There are still lots of open questions – if we warm the planet by a few degrees, are we going to collapse a big part of Antarctica or a small part? How much ice will melt?”


To learn more about ice sheets, sea levels, and using computer models to figure out how the shoreline looked thousands of years ago, tune in to Schmitty Thompson’s episode on Inspiration Dissemination this upcoming Sunday evening at 7 PM PST. Catch the show live by streaming on https://kbvrfm.orangemedianetwork.com/, or check out the show later wherever you get your podcasts!

Thompson was also recently featured on Alie Ward’s popular podcast Ologies. You can catch up with all things geology by checking out their episode here.

Warming waters, waning nutrition

Here at Inspiration Dissemination, we are fascinated by the moments of inspiration that lead people to pursue graduate studies. For our next guest, an experience like this came during a boat trip accompanying the National Oceanic and Atmospheric Administration (NOAA) on a research expedition. Becky Smoak, an M.S. student in OSU’s Marine Resource Management program, remembers feeling in awe of the vibrant array of marine life that she saw, including whales, sunfish, and sharks. Growing up on a farm in eastern Washington, Becky had always wanted to be a veterinarian. During her undergraduate studies at Washington State University, she came to feel that the culture of pre-veterinary students was too cutthroat. In search of something more collaborative, she came to Oregon State in summer 2019 for a Research Experience for Undergrads (REU) and was impressed by the support and inclusivity of her research mentors. A couple years later, Becky is now on the cusp of graduation after her time spent studying marine life.

Becky’s graduate work is the continuation of a long-running collaboration between Oregon State and NOAA out of the Hatfield Marine Science Center in Newport. Beginning in 1996 under the direction of Bill Peterson, a team of researchers has monitored oceanic conditions along a route called the Newport Hydrographic, which extends in a straight line eastward from the Oregon Coast and intersects the northern part of the vast Californian Current. The team takes samples of ocean water at fixed points along the route and analyzes the concentrations of plankton and other organisms or compounds of interest. 

Becky Smoak, teaching on the OSU research vessel The Elakha.

The specific biochemicals that Becky studies are Omega-3 fatty acids. In a set of experiments from the 1930s, rats fed with a diet poor in Omega-3 fatty acids eventually died, demonstrating that these compounds are essential to life and are not produced by mammals. Two types of Omega-3 fatty acids, called EPA and DHA, can only be synthesized by phytoplankton, microscopic photosynthetic organisms that live in the ocean. The ability of phytoplankton to produce fatty acids is intimately linked with oceanic temperature. Studies have shown that increases in sea surface temperature and decreases in nutrient availability can decrease the quality of fatty acids in phytoplankton, thus decreasing food availability and quality in the marine environment. Fatty acid levels have downstream effects on the ecosystem, for example on copepods, a type of zooplankton that feeds on phytoplankton. Becky’s team affectionately refers to the copepod colony of the chilly northern Pacific as the “cheeseburger” copepods, in contrast to the “celery” copepods of the southern Pacific colony. The present-day effect of temperature also points to a key ecological challenge, as warming oceans due to climate change could disrupt the supply of this vital nutrient.

In her thesis work, Becky seeks to untangle the contributions of phytoplankton community structure to oceanic Omega-3 fatty acid levels. She uses a set of statistical methodologies called nonmetric multidimensional scaling to uncover correlations in the datasets. A particularly interesting instrument used to collect her data is a flow cytometry robot dubbed ‘Lucy’. Lucy uses advanced imaging to count individual plankton and characterize their sizes. This yields an improvement in accuracy over older monitoring techniques that assumed a fixed size for all plankton. Becky’s goal for finishing her thesis is to create a statistical procedure for predicting fatty acid availability given information on phytoplankton population structure.

To hear more about Becky’s journey to OSU, her experiences as a first-generation college student, and the fascinating role of Omega-3s in marine ecosystems, be sure to tune in this Sunday October 9th at 7pm on KBVR.

This article was written by Joseph Valencia.

The non-Ghostbusting Venkman: a virus that “eats” marine bacteria

Have you ever considered that a virus that eats bacteria could potentially have an effect on global carbon cycling? No? Me neither. Yet, our guest this week, Dr. Holger Buchholz, a postdoctoral researcher at OSU, taught me just that! Holger, who works with Drs. Kimberly Halsey and Stephen Giovannoni in OSU’s Department of Microbiology, is trying to understand how a bacteriophage (a bacteria-eating virus), called Venkman, impacts the metabolism of marine bacterial strains in a clade called OM43.

Bacteria that are part of the OM43 clade are methylotrophs, in other words, these bacteria eat methanol, a type of volatile organic compound. It is thought that the methanol that the OM43 bacteria consume are a by-product of photosynthesis by algae. In fact, OM43 bacteria are more abundant in coastal waters and are particularly associated with phytoplankton (algae) blooms. While this relationship has been shown in the marine environment before, there are still a lot of unknowns surrounding the exact dynamics. For example, how much methanol do the algae produce and how much of this methanol do the OM43 bacteria in turn consume? Is methanol in the ocean a sink or a source for methanol in the atmosphere? Given that methanol is a carbon compound, these processes likely affect global carbon cycles in some way. We just do not know how much yet. And methanol is just one of many different Volatile Organic Carbon (VOC) compounds that scientists think are important in the marine ecosystem, and they are probably consumed by bacteria too!

Depiction of the carbon cycle within the marine food web. DOM means Dissolved Organic Material, POM stands for Particulate Organic Material. This refers to all the things that are bound within cells that gets released when for example viruses destroy cells. 

All of this gets even more complicated by the fact that a bacteriophage, by the name of Venkman, infects the OM43 bacteria. If you are a fan of Ghostbusters and your mind is conjuring the image of Bill Murray in tan coveralls at the sound of the name Venkman, then you are actually not at all wrong. During his PhD, which he conducted at the University of Exeter, part of Holger’s research was to isolate the bacteriophage that consumes OM43 bacteria (which he successfully did). As a result, Holger and his advisor (Dr. Ben Temperton, who is a big Ghostbusters fan) were able to name the bacteriophage and called it Venkman. Holger’s current work at OSU is to try and figure out how the Venkman bacteriophage affects the metabolism of methanol in OM43 bacteria and the viral influence on methanol production in algae. Does the virus increase the bacteria’s methanol metabolism? Decrease it? Or does nothing happen at all? At this point, Holger is not entirely sure what he is going to find, but whatever the answer, there would be an effect on the amount of carbon in the oceans, which is why this work is being conducted.

Holger is currently in the process of setting up experiments to answer these questions. He has been at OSU since February 2022 and has funding to conduct this work for three years from the Simons Foundation. Join us live on Sunday at 7 pm PST on 88.7 KBVR FM or https://kbvrfm.orangemedianetwork.com/ to hear more about Holger’s research and how a chance encounter with a marine biologist in Australia set him on his current career path! Can’t make it live, catch the podcast after the episode on your preferred podcast platform!

Microbial and biochemical community dynamics in low-oxygen Oregon waters

Much like Oregon’s forests experience wildfire seasons, the waters off the Oregon coast experience what are called “hypoxia seasons”. During these periods, which occur in the summer, northern winds bring nutrient-rich water to the Eastern Current Boundary off the Oregon Coast. While that might sound like a good thing, the upwells bring a bloom of microscopic organisms such as phytoplankton that consume these nutrients and then die off. As they die off, they sink and are then decomposed by marine microorganisms. This process of decomposition removes oxygen from the water, creating what’s called an oxygen minimum zone, or OMZs. These OMZs can span thousands of square miles. While mobile organisms such as fish can escape these areas and relocate, place-bound creatures such as crabs and bottom-dwelling fish can perish in these low oxygen zones. While these hypoxia seasons can occur due to natural phenomena, stratification of the water column due to other factors such as climate change can increase the frequency or severity of these seasons.

2021 was one of the worst years on record for hypoxic waters off the Western coast of the United States. A major contributing factor was the extremely early start to the upwelling triggered by strong winds. Measurements of dissolved oxygen and ocean acidity were high enough to be consistent with conditions that can lead to dead zones, and this is exactly what happened. Massive die-offs of crabs are concerning as the harvesting of Dungeness crab is one of the most lucrative fishing industries in the state. Other species and organisms move into shallower waters, disturbing the delicate balance of the coastal ecosystems. From the smallest microbe to the largest whale, almost every part of the coast can be affected by hypoxia season. 

Our guest this week is Sarah Wolf, a fourth year PhD candidate in the Department of Microbiology here at Oregon State. Sarah, who is co-advised by Dr. Steve Giovannoni and Dr. Francis Chan, studies how microbes operate in these OMZs. Her work centers around microbial physiology and enzyme kinetics, and how these things change over time and in varying oxygen concentrations. To do this, she spent her second year developing a mesocosm, which is a closed environment that allows for the study of a natural environment, which replicates conditions found in low oxygen environments. 

Sarah Wolf, a fourth year PhD Candidate in the department of Microbiology, in her lab

Her experiments involve hauling hundreds of liters of ocean water from the Oregon coast back to her lab in Nash Hall, where she filters and portions it into different jugs hooked up to a controlled gas delivery system which allows her to precisely control the concentration of oxygen in the mesocosm. Over a period of four months Sarah samples the water in these jugs to look at the microbial composition, carbon levels, oxygen respiration rates, cell counts, and other measures of the biological and chemical dynamics occurring in low oxygen. Organic matter can get transformed by different microorganisms that “eat” different pieces through the use of enzymes, but many enzymes which can break down large, complex molecules require oxygen, and in low oxygen conditions, this can be a problem for the breakdown and accumulation of organic matter. This is the kind of phenomenon that Sarah is studying in these mesocosms, which her lab affectionately refers to as the “Data Machine”. 

Sarah’s journey into science has been a little nontraditional. A first generation college student, she started out her education as a political science major at Montana State before moving to the University of the Virgin Islands for a semester abroad. At the time she wasn’t really sure how to get into research or science as a career. During this semester her interest in microbiology was sparked during an environmental science course which led to her first research experience, studying water quality in St. Thomas. This experience resulted in an award-winning poster at a conference, and prompted Sarah to change her major to Microbiology and transfer to California State University Los Angeles. Her second research experience was very different – an internship at NASA’s Jet Propulsion Laboratory studying cleanroom microbiology, which resulted in a publication identifying two novel species of Bacillus isolated from the Kennedy Space Center. Ultimately Sarah’s journey brought her here to Oregon State, which she was drawn to because of its strong marine microbiology research program.

Sarah works on the “Data Machine”

But Sarah’s passion for science doesn’t stop at the lab: during the Covid-19 pandemic, she began creating and teaching lessons for children stuck at home. During this time she taught over 60 kids remotely, with lessons about microbes ranging from marine microbiology to astrobiology and even how to create your own sourdough starter at home. Eventually she compiled these lessons onto her website where parents and teachers alike can download them for use in classrooms and at home. She also began reviewing children’s science books on her Instagram page (@scientist.sarahwolf), and inviting experts in different fields to participate in livestreams about books relating to their topics. A practicing Catholic, she also shares thoughts and resources about religion and science, especially topics surrounding climate science. With around 12k followers, Sarah’s outreach on Instagram has certainly found its audience, and will only continue to grow. 

If you’re curious about microbes in low oxygen conditions, what it’s like to be a science educator and social media influencer, or want to hear more about Sarah’s journey in her own words, tune in at 7 PM on March 13th to catch the live episode at 7 PM PST on 88.7 FM Corvallis, online at https://kbvrfm.orangemedianetwork.com – or you can catch this episode after the show airs wherever you get your podcasts! 

Global ocean modeling, with a microscope on Micronesia

How could an equation developed by a German mathematician in 1909 help Micronesian conservation networks plan for the future in the face of climate change? 

In this week’s episode, we interview Dr. Steven Johnson, a graduate of Oregon State University’s Geography graduate program. Steven completed his doctorate earlier in 2021, under the guidance of Dr. James Watson, a professor in the College of Earth, Ocean, and Atmospheric Sciences. He’s now a postdoctoral fellow at Arizona State University. During his time at Oregon State, the focus of his work was oceans. “I study the ocean – in particular, people’s relationship with the ocean. The condition of the ocean has implications for people all over the world and millions depend on it for their livelihood,” he explains.

Steven Johnson, a recent graduate of OSU and now a postdoctoral fellow at Arizona State University

“There used to be this idea that the ocean was ‘too big to fail’, but Oregon State University Distinguished Professor and White House Deputy Director for Climate and the Environment Jane Lubchenco made the point that ‘the ocean is too big to fail, but too big to ignore,’” Steven recounts. “Not a single part of the ocean has not been impacted by people.” Plastic waste, rising temperatures, increasing acidification, and other byproducts of human activity have been changing the ocean as we know it, and it will continue to worsen if the problem can’t be solved. One challenge that arises as a result of these changes is the future of aquatic resource management and conservation programs, which are designed to work in current ocean and climate conditions.

So how does Steven’s research tackle these problems? In the first chapter of his thesis, he developed a novel model for predicting the way the ocean will change due to climate change. This approach is titled the Ocean Novelty Index, or the ONo Index. The Ocean Novelty Index quantifies the relative impact of climate change across all parts of the ocean, using a statistical metric applied to six different ocean surface variables (chlorophyll, O2, pH, sea surface temperature, silica, and zooplankton.) The metric is derived from the Hellinger distance, developed by a German mathematician in 1909, which is a nonparametric analysis that measures the similarity and dissimilarity between two distributions and their overlap. The baseline, or ‘normal’, conditions are derived from the period between 1970-2014, a 50 year period which recognizes 1970 as the birth of the modern Western climate movement. The model can then be used to assess and predict what climate change will do to one part of the ocean, and compare it to how that part of the ocean looked previously. The model better encapsulates the dynamic and unpredictable changes of the ocean resulting from climate change, as opposed to just rising temperatures. 

In addition to the development of this climate change index, Steven’s research also focused on conservation networks and initiatives across Micronesia, the Caribbean, and Southeast Asia. These networks and cooperatives are collaborative efforts between regional governments to meet certain conservation goals, taking into account the differing social, cultural, and economic needs of the different countries involved. Part of Steven’s work has focused on applying the ONo index on a local scale, to help determine what changes may occur in the regions as well as where. What will the regions of these networks look like at different points as the climate changes, and how can we create strong policies and political relationships in these cooperatives and their respective countries to ameliorate potential issues in the future? Steven discusses these topics and more with us on this week’s ID podcast.

If you are interested in learning more about the ONo index and Steven’s work, you can read his paper here.

This post was written by Grace Deitzler