Category Archives: College of Agricultural Sciences

Climate change, carbon, roots vs shoots, and why soil is more than just dirt

For starters, soil and dirt are not the same thing (contrary to my own belief). First of all, dirt is in fact soil that has been removed from its intended location. For example, the stuff on your shoes after you go hiking in the forest or the grit under your fingernails after you go dig around in your garden, that’s all dirt. The stuff that is left untouched in the forest and in the garden, that’s all soil. Secondly, soil is super important for a number of reasons. One of the key reasons being that it has the potential to help us reduce the amount of carbon in our atmosphere on human timescales, and therefore, mitigate the effects of climate change. And Adrian Gallo is right in the nitty-gritty of it all. 

Adrian is a 4th year PhD student in the Department of Crops and Soil Sciences working with Dr. Jeff Hatten, who was also his Master’s advisor. While Adrian’s Master’s work was focused on understanding how carbon and water move in Oregon soils under intensive forest management, his PhD is looking at soils from a much wider and more diverse range of habitats and ecosystems. Specifically, the soil cores are from 43 different locations across North America spanning 20 different ecoclimatic zones, ranging from the Alaskan Arctic Tundra to the southern tip of Florida. By analyzing these samples, Adrian is making a continental-scale assessment of soil organic matter and how similar or different it is across these ecoclimatic zones. In particular, Adrian is looking at carbon. Carbon is unique to look at in soils because it is cycling in human timescales, unlike carbon in rocks and oceans, which cycles on geologic timescales. What this means is that essentially we can directly manage and influence the carbon on our landscapes. However, before we can do that, we need to understand why some carbon stays in soil much longer than other carbon (50,000 years vs 1 week) and how different microbes have different abilities to use these different kinds of carbon. 

While it may not sound like it to many of us, the work that Adrian is doing is soil-scientifically speaking quite ‘basic’. It is ‘basic’ because soil scientists today are only now realizing how little we actually know and understand about how carbon works and cycles within soil. The reason being that “we were using essentially the same analytical methods for more than 100 years, and our predictions and climate models were built using that data. It’s only in the last 25 years that we have had instruments sensitive enough to test some of these predictions, and in some cases we’ve found that our models are completely wrong.” (NEON Science). 

Many of us probably learned about how cycling of elements, such as nitrogen, calcium, and carbon, works in middle school. The terrestrial carbon cycle was likely explained in the following way; a tree grows, its leaves fall, the leaves decompose, the nutrients go back into the soil, the tree uses the nutrients, which includes carbon. However, what Adrian and many other soil scientists are finding is that the carbon cycle isn’t as cyclical as we thought it was, and as we perhaps wish it would. Additionally, our belief that most of the carbon that finds its way into soils is shoot-derived (aka from the leaves or from above the ground) is also being proven flawed, in some part by Adrian’s research. After analyzing the soil cores from his 43 sites, Adrian found that most of the carbon in soil is looking like it is in fact root-derived. 

You may be thinking to yourself, why should I care about how much carbon is in the soil and where it comes from and how long it stays there. Well, soil is actually the most important terrestrial carbon sink, storing an estimated 4,100 gigatons of carbon globally, which is more than the atmosphere (~590 Gt) and organisms (650 Gt) store. And the truth of the matter is that we want carbon in our soil. In fact, we want a whole lot more in there. Not only would having more carbon in our soil be beneficial to our climate (as we would be capturing and storing more of the atmospheric carbon in our soils rather than have it out in the atmosphere), but it is also beneficial from an agricultural perspective. If you put carbon in soil, it increases its water holding capacity, meaning farmers don’t have to irrigate as much, it increases the amount of nutrients in the soil, and as a consequence of both, it means that a more diverse range of crops can be planted. There are so many downstream benefits of putting carbon back into soil that is has the potential to make farmers much safer in bad drought or flood years.

Another really exciting component of Adrian’s research is how collaborative and interdisciplinary it is. One of the best examples of this is where he got his 43 soil cores from. You see, Adrian didn’t actually have to go to each of his 43 cross-continental sites (which would have been a nightmare temporally, logistically, financially, and many more words ending in -ally). Instead, he and his advisor were able to convince a team of researchers who were already going to these sites as part of an NSF-funded project called NEON (National Ecological Observatory Network), to send him the 1-m average length cores, which the NEON group were actually planning on not using and dumping. Furthermore, Adrian has joined forces with researchers from diverse backgrounds to look at these cores from totally different angles. While Adrian represents the role of chemist in the group, there is also an ecologist, mineralogist, and a statistician, who are all fitting different pieces of the puzzle together.

In Adrian’s own words, “it’s a really exciting time to be in the field of biogeochemistry because that’s basically what soil is – some mixture of biology, the chemistry that is involved, and the parent material– the rock itself–dictates a lot of the reactions that can occur. We have taken that for granted for a really long time but I really enjoy the complexity of it and having specialists come in to look at this problem from lots of different angles has been really great.”.

When Adrian is not in the lab breaking apart soil cores or in his office thinking about soil, you’ll probably find him speeding around in the woods on his bike…covered in soil. Source: Twitter.

To hear more about Adrian’s research and also about his journey to OSU and more on his personal background, tune in on Sunday, January 12 at 7 PM on KBVR Corvallis 88.7 FM or stream live. Also, make sure to follow Adrian on Twitter for updates on all things soil and check out a recording of a talk he recently gave at the American Society of Agronomy and Crop Science Society of America joined conference!

[Unfortunately due to a conflict with OSU Athletics schedule promoting a game, this on-air interview did not take place. The podcast/on-air interview will occur later in 2020]

What ties the Panama Canal, squeaky swing sets, and the Smithsonian together? Birds of course!

Have you ever wondered why you see birds in some places and not in others? Or why you see a certain species in one place and not in a different one? Birds have wings enabling them to fly so surely we should see them everywhere and anywhere because their destination options are technically limitless. However, this isn’t actually the case. Different bird species are in fact limited to where they can and/or want to go and so the question of why do we see certain birds in certain areas is a real research question that Jenna Curtis has been trying to get to the bottom of for her PhD research.

Jenna is a 4th year PhD candidate working with Dr. Doug Robinson in the Department of Fisheries & Wildlife. Jenna studies bird communities to figure out which species occur within those communities, and where and why they occur there. To dial in on these big ecological questions, Jenna focuses on tropical birds along the Panama Canal (PC). PC is a unique area to study because there is a large man-made feature (the canal) mandating what the rest of the landscape looks and behaves like. Additionally, it’s short, only about 50 miles long, however, it is bookended by two very large cities, Panama City (which has a population over 1 million people) and Colón. Despite the indisputable presence and impact of humans in this area, PC is still flanked by wide swaths of pristine rainforest that occur between these two large cities as well as many other types of habitat.

Barro Colorado Island can be seen in the centre of the Panama Canal.

A portion of Jenna’s PhD research focuses on the bird communities found on an island in the PC called Barro Colorado Island (BCI), which is the island smack-dab in the middle of the canal. To put Jenna’s research into context, we need to dive a little deeper into the history of the PC. When it was constructed by the USA (1904-1914), huge areas of land were flooded. In this process, some hills on the landscape did not become completely submerged and so areas that used to be hilltops became islands in the canal. BCI is one such island and it is the biggest one of them in the PC. In the 1920s, the Smithsonian acquired administrative rights for BCI from the US government and started to manage the island as a research station. This long-term management of the island is what makes BCI so unique to study as we have studies dating back to 1923 from the island but it has also been managed by the Smithsonian since 1946 so that significant development of infrastructure and urbanization never occurred here.

Large cargo vessels pass next to BCI on their transit of the Panama Canal

Now back to Jenna. Over time, researchers on the island noticed that fewer bird species were occurring on the island. There are now less species on the island than would be expected based on the amount of available habitat. Therefore, Jenna’s first thesis chapter looks at which bird species went extinct on BCI after the construction of PC and why these losses occurred. She found that small, ground-dwelling, insectivore species were the group to disappear first. Jenna determined that this group was lost because BCI has started to “dry out”, ecologically speaking, since the construction of PC. This is because after the PC was built, the rainforest on BCI was subjected to more exposure from the sun and wind, and over time BCI’s rainforest has no longer been able to retain as much moisture as it used to. Therefore, many of the bird species that like shady, cool, wet areas weren’t able to persist once the rainforest started becoming more dry and consequently disappeared from BCI.

Another chapter of Jenna’s thesis considers on a broader scale what drives bird communities to be how they are along the entire PC, and what Jenna found was that urbanization is the number one factor that affects the structure and occurrence of bird communities there. The thing that makes Jenna’s research and findings even more impactful is that we have very little information on what happens to bird communities in tropical climates under urbanization pressure. This phenomenon is well-studied in temperate climates, however a gap exists in the tropics, which Jenna’s work is aiming to fill (or at least a portion of it). In temperate cities, urban forests tend to look the same and accommodate the same bird communities. For example, urban forest A in Corvallis will have pigeons, house sparrows, and starlings, and this community of birds will also be found in urban forest B, C, D, etc. Interestingly, Jenna’s research revealed that this trend was not the case in Panama. She found that bird communities within forest patches that were surrounded by urban areas were significantly different to one another. She believes that this finding is driven by the habitat that each area may provide to the birds. 

Jenna has loved birds her entire life. To prove to you just how much she loves birds, on her bike ride to the pre-interview with us, she stopped on the road to smash walnuts for crows to eat. Surprisingly though, Jenna didn’t start to follow her passion for birds as a career until her senior year of her undergraduate degree. The realization occurred while she was in London to study abroad for her interior design program at George Washington University in D.C. where on every walk to school in the morning she would excitedly be pointing out European bird species to her friends and classmates, while they all excitedly talked about interior design. It was seeing this passion among her peers for interior design that made her realize that interior design wasn’t the passion she should be pursuing (in fact, she realized it wasn’t a passion at all), but that birds were the thing that excited her the most. After completely changing her degree track, picking up an honor’s thesis project in collaboration with the Smithsonian National Zoo on Kori bustard’s behavior, an internship at the Klamath Bird Observatory after graduating, Jenna started her Master’s degree here at OSU with her current PhD advisor, Doug Robinson in 2012. Now in her final term of her PhD, Jenna hopes to go into non-profit work, something at the intersection of bird research and conservation, and public relations and citizen science. But until then, Jenna will be sitting in her office (which houses a large collection of bird memorabilia including a few taxidermized birds) and working towards tying all her research together into a thesis.

To hear more about Jenna’s research, tune in on Sunday, October 6th at 7 PM on KBVR 88.7 FM, live stream the show at http://www.orangemedianetwork.com/kbvr_fm/, or download our podcast on iTunes!

Are Microplastics the New Fish Food?

Geologists have considered an entirely new geologic era as a result of the impact humans are having on the planet. Some plastic material in our oceans near Hawaii along are hot magma vents and is being cemented together with sand, shells, fishing nets and forming never before existing material — Plastiglomerates. This new rock is a geologic marker providing evidence of our impact that will last centuries. Although rocks seem inert, that same plastic material floating around our oceans is constantly being eaten, purposefully and accidentally, by ocean creatures from as small as plankton to as large as whales and we’re just beginning to understand the ubiquity of microplastics in our oceans and food webs that humans depend on.  

Our guest this evening is Katherine Lasdin, a Masters student in the Fisheries and Wildlife Department, and she has to go through extraordinary steps in her lab to measure the quantity and accumulation of plastics in fish. Her work focuses on the area off the coast of Oregon, where she is collecting black rockfish near Oregon Marine Reserves and far away from those protected areas. These Marine Reserves are “living laboratory” zones that do not allow any fishing or development so that long-term monitoring and research can occur to better understand natural ecosystems. Due to the protected nature of these zones, fish may be able to live longer lives compared to fish who are not accessing this reserve. The paradox is whether fish leading longer lives could also allow them to bioaccumulate more plastics in their system compared to fish outside these reserves. But why would fish be eating plastics in the first place? 

These are the locations of Oregon’s Marine Reserves. The sampling for juveniles and adult black rockfish is occurring at Cape Foulweather which is between the Cascade head and Otter Rock Reserves. PC:
Black rockfish are a common fish off the Oregon coast and due to their abundance it’s a great study species for this research.

Plastic bottles, straws, and fishing equipment all eventually degrade into smaller pieces. Either through photodegradation from the sun rays, by wave action physically ripping holes in bottles, or abrasion with rocks as they churn on our beaches. The bottle that was once your laundry detergent  is now a million tiny fragments, some you can see but many you cannot. And they’re not just in our oceans either. As the plastics degrade into even tinier pieces, they can become small enough that, just like dust off a farm field, these microplastics can become airborne where we breathe them in! Microplastics are as large as 5mm (about the height of a pencil eraser) and they are hoping to find them as small as 45 micrometers (about the width of a human hair). To a juvenile fish their first few meals is critical to their survival and growth, but with such a variety of sizes and colors of plastics floating in the water column it’s often mistaken for food and ingested. In addition to the plastic pieces we can see with our eyes there is a background level of plastics even in the air we breathe that we can’t see, but they could show up in our analytical observations so Katherine has a unique system to keep everything clean. 

In order to quantify the amount of plastics in fish, you have to digest some of the fish guts. PC: Katherine Lasdin

Katherine is co-advised by Dr. Susanne Brander who’s lab studies microplastics in marine ecosystems. In order to keep plastics out of their samples, they need to carefully monitor the air flow in the lab. A HEPA filtration laminar flow hood blows purified air towards samples they’re working with in the lab and pushes that clean air out into the rest of the lab. There is a multi-staged glassware washing procedure requiring multiple ethanol rinses, soap wash, deionized water rinses, a chemical solvents rinse, another ethanol, and a final combustion of the glass in a furnace at 350°C for 12-hours to get rid of any last bit of contamination. And everyday that someone in Dr. Brander’s lab works in the building they know exactly what they’re wearing; not to look cool, but to minimize any polyester clothing and maximize cotton clothing so there is even less daily contamination of plastic fibers. These steps are taken because plastics are everywhere, and Katherine is determined to find out just big the problem may be for Oregon’s fish.  

Katherine Lasdin working in the laminar flow hood that blows purified air towards the samples in Dr. Brander’s lab. PC: Cheyenne Pozar

Be sure to listen to the interview Sunday 7PM, either on the radio 88.7KBVR FM or live-stream, to learn how Katherine is conducting her research off the coast of Oregon to better understand our ocean ecosystems in the age of humans.

Listen to the podcast episode!

On this episode at the 16:00 mark we described how every time you wash clothing you will loose some microfibers; and how a different student was looking at this material under microscopes. That person is Sam Athey, a PhD student at the University of Toronto who also studies microplastics.

Environmental planning in an age of human-animal interactions

Many people enjoy their time visiting wildlands whether it means hiking, birding, or searching for exotic mushrooms, but as more people visit the outdoors there are more and more layers of expected uses for a single patch of forest. Since a 1960 Congressional act, National Forests have been designated multi-use which includes managing the land for “outdoor recreation, range, timber, watershed, and wildlife and fish purposes.” Hikers and bird-enthusiasts may have overlapping expectations of calm and serenity when stepping foot on the trailhead, but that’s a far cry from what a mountain biker wants out of a trail system where speed and steepness are prioritized. Additionally, there are demands for timber production vital to rural community survival and finding recreational areas for hunting and fishing. With all these expected uses, there is no doubt there will be conflicts. The vexing questions that simmer for land managers is understanding where on the landscape federal dollars can be utilized for maximum public good.

The way we’ve approached that question has changed over time. In the past, these management decisions were answered with a pure ecological understanding of the area such as: which soils can support mushrooms growth, or what trees species can support a bird species of interest. Making decisions completely within the ecological framework could miss the fact that the local community prioritizes river access because of its strength as a tourism hub for whitewater rafting, for example. Instead of spending money on a bird exploration trail they may prioritize the repair of a boat ramp or a wildfire prevention treatment around a heavily used section of river that is susceptible to summer fires. The latter two options are likely to have much stronger public support, gain local advocates in the process and, in the long run, make it possible to expand the range of successful recreational programs. Those ideas are examples of an idea where the ecology of the land and the social factors are taken into account to better focus management decisions in a process called Human Ecology Mapping.

Jackie Delie and brother, Anthony Delie, exploring the Great Bear Rainforest, British Columbia Canada

If we can take into account the ecological factors of the area that bracket what is physically possible on the land and better understand the priorities of the local community, then land managers can make more informed decisions that are less likely to result in user conflicts and are more likely to create long-term positive impacts on the relationships humans have with the land. Our guest is Jackie Delie a Masters student in the Department of Fisheries and Wildlife who is using the Human Ecology Mapping technique in a more visceral relationship: human and black bear interactions in Oregon. Jackie is advised by Dr. Kelly Biedenweg, a social scientist, who previously had another student exploring social spatial data for sustainable management in the Hood Canal between Oregon and Washington. This study suggested that this is a method that can yield positive results across a variety of user groups.

Black bear sighting on the river bank in the Great Bear Rainforest, British Columbia Canada

Furry and curious or big and scary? Your immediate thoughts about black bears is likely related to your previous experiences with them. If you’ve seen bears napping in the sun from behind a glass enclosure at a zoo, you probably think they’re gentle giants. If you’re chasing bears out of your backyard while they scatter trash across your front lawn every week, you probably have different feelings. You may expect the more you are exposed to bears the more you know about them; however, what kind of exposure is critical to your feeling about bears. If you’re a hunter or hiker, you likely have very positive experiences with bears compared to a homeowner nestled in the wildland urban interface but does not recreate in the forest. Jackie is leveraging the spatial GPS data of black bears killed over the past decade, as reported from the Oregon Department of Fisheries and Wildlife, and examining how the cluster of those points relate to how people use the landscape and their experiences and values.

Jackie Delie checking on camera trap cameras in black bear habitat on the urban-wildlife fringe in King County, Washington

This is the first study of its kind that looks at the human dimensions of human and black bear interactions in Oregon, as Oregon is one of the few places that mandate GPS points be recorded for black bear kills. Jackie collected in-person interviews at 18 different trailheads throughout Oregon asking participants a variety of questions. One of them is to physically draw where in Oregon they use the landscape and for what use –  hiking, hunting, rafting, or another activity.  Using both spatial and social datasets she may begin to elucidate not only where there are overlapping user areas, but how those areas may influence the human perceptions of black bears in the environment. The larger goal of Jackie’s project is to help inform the management plan through the Oregon Department Fish and Wildlife so they can make better decisions on where to prioritize resources on the landscape to better understand why human opinions differ about black bears.

Jackie Delie conducting research in the Panama rainforest on the behavior of mantled howler monkeys (Alouatta palliata) or you can say solo research time in the Panama rainforest

Merging two (somewhat) disparate fields of science is rare for a graduate degree, but knowing Jackie’s road to graduate school makes it seem rather natural. She conducted her undergraduate degree in Switzerland doing countless endeavors from Australia to Kenya learning about new foods, cultures, and sciences. After many travels and internships, she knew she wanted to purse graduate school. It was almost one year from the first time Jackie contacted her advisor until she became a student here at Oregon State.

Be sure to listen to the interview Sunday 7PM, either on the radio 88.7KBVR FM or live-stream, to learn how a holistic approach to land management can ensure a more successful project outcome, and how Jackie traveled the world and ended up back in the Pacific Northwest, an area she calls home.

Dr. Biedenweg Research Website

Jackie Delie’s Website

 

Zebrafish sentinels: studying the effects of cadmium on biology and behavior

Cadmium exposure is on the rise

There’s a good chance you might have touched cadmium today. A heavy metal semi-conductor used in industrial manufacturing, cadmium is found in batteries and in some types of solar panels. Fertilizers and soil also contain cadmium because it is present in small levels in the Earth’s crust. The amount of cadmium in the environment is increasing because of improper disposal of cell phone batteries, contaminating groundwater and soil. This is a problem that impacts people all over the world, particularly in developing countries.

Plants take up cadmium from the soil, which is how exposure through food can occur. Leafy greens like spinach and lettuce can contain high levels of cadmium. From the soil, cadmium can leach into groundwater, contaminating the water supply. Cadmium is also found in a variety of other foods, including chocolate, grains and shellfish, as well as drinking water.

Cadmium has a long half-life, reaching decades, which means that any cadmium you are exposed to will persist in your body for a long time. Once in the body, cadmium ends up in the eyes or can displace minerals with similar chemical properties, such as zinc, copper, iron, and calcium. Displacement can cause grave effects related to the metabolism of those minerals. Cadmium accumulation in the eyes is linked to age-related macular degeneration, and for people in the military and children, elevated cadmium is linked to psychosocial and neurological disorders.

Read more about cadmium in the food supply:



Using zebrafish to study the effects of cadmium

Delia Shelton, a National Science Foundation post-doctoral fellow in the Department of Environmental and Molecular Toxicology, uses zebrafish to investigate how cadmium exposure in an individual affects the behavior of the group. Exposing a few individuals to cadmium changes how the group interacts and modifies their response to novel stimuli and environmental landmarks, such as plants. For example, poor vision in a leader might lead a group closer to predators, resulting in the group being more vulnerable to predation.

Zebrafish

As part of her post-doctoral research, Delia is asking questions about animal behavior in groups: how does a zebrafish become a leader, how do sick zebrafish influence group behavior, and what are the traits of individuals occupying different social roles? These specific questions are born from larger inquiries about what factors lead to individual animals wielding inordinately large influence on a group’s social dynamic. Can we engineer groups that are resilient to anthropogenic influences on the environment and climate change?

Zebrafish

Zebrafish are commonly used in biomedical research because they share greater than 75% similarity with the human genome. Because zebrafish are closely related to humans, we can learn about human biology by studying biological processes in zebrafish. Zebrafish act as a monitoring system for studying the effects of compounds and pollution on development. It is possible to manipulate their vision, olfactory system, level of gene expression, size, and aggression level to study the effects of pollutants, drugs, or diseases. As an added benefit, zebrafish are small and adapt easily to lab conditions. Interestingly, zebrafish are transparent, so they are great for imaging. Zebrafish have the phenomenal ability to regenerate their fins, heart and brain. What has Delia found? Zebrafish exposed to cadmium are bolder and tend to be attracted more to novel stimuli, and they have heightened aggression.

Read more about zebrafish:

ZFIN- Zebrafish Information Network – https://zfin.org/
Zebrafish International Research Center in Eugene Or – http://zebrafish.org/home/guide.php



What led Delia to study cadmium toxicity in zebrafish?

As a child, Delia was fascinated by animals and wanted to understand why they do the things they do. As an undergrad, she enjoyed research and pursued internships at Merck pharmaceutical, a zoo consortium, and Indiana University where she worked with Siamese fighting fish. She became intrigued by social behavior, social roles, and leadership. Delia studied the effects of cadmium in grad school at Indiana University, and decided to delve into this area of research further.

Delia began her post-doctoral work after she finished her PhD in 2016. She was awarded an NSF Postdoctoral Fellowship to complete a tri-institute collaboration: Oregon State University, Leibniz Institute for Freshwater Ecology and Inland Fisheries in Berlin, Germany, and University of Windsor in Windsor, Ontario. She selected the advisors she wanted to work with by visiting labs and interviewing past students. She wanted to find advisors she would work well with and who would help her to accomplish her goals. Delia also outlined specific goals heading into her post-doc about what she wanted to accomplish: publish papers, identify collaborators, expand her funding portfolio, learn about research institutes, and figure out if she wanted to stay in academia.

Research commercialization and future endeavors

During her time at OSU, Delia developed a novel assay to screen multiple aspects of vision, and saw an opportunity to explore commercialization of the assay. She was awarded a grant through the NSF Innovation Corps and has worked closely with OSU Accelerator to pursue commercialization of her assay. Delia is now wrapping up her post-doc, and in the fall, she will begin a tenure track faculty position at University of Tennessee in the Department of Psychology, where she will be directing her lab, Environmental Psychology Innovation Center (E.P.I.C) and teaching! She is actively recruiting graduate students, postdocs, and other ethnusiatic individuals to join her at EPIC.

Please join us tonight as we speak with Delia about her research and navigation of the transition from PhD student to post-doc and onwards to faculty. We will be talking to her about her experience applying for the NSF Postdoctoral Fellowship, how she selected the labs she wanted to join as a post-doc, and her experience working and traveling in India to collect zebrafish samples.

Tune in to KBVR Corvallis 88.7 FM or stream the show live on Sunday, April 7th at 7 PM. You can also listen to the episode on our podcast.

Feather collections and stressed-out owls

Ashlee Mikkelsen holding a juvenile northern spotted owl. Photo courtesy Ashlee Mikkelsen.

For six months out of every year, Ashlee Mikkelsen spends her days hiking for miles off-trail in the Ponderosa pine-filled forests of central Washington, hooting like an owl, and carefully listening for responses. These days, responses can be few and far between. You see, Ashlee isn’t just a wildlife enthusiast; she is a research assistant in a long-term US Forest Service monitoring program focused on the northern spotted owl.

Since being listed as threatened by the US Fish and Wildlife Service in 1990, populations of northern spotted owls have continued to decline. In some areas, the number of spotted owls has decreased by more than half in only 20 years (see (Dugger et al. (2016)). Northern spotted owls are inhabitants of old-growth forests. Although northern spotted owls historically could be found in almost every forest from northern California to British Columbia, as forests have shrunk in size through timber harvesting and through changing land use, the amount of suitable habitat has drastically decreased. A second major contributor to the decline of the northern spotted owl is arrival during the last century of the barred owl, which are native to northeastern North America. Barred owls competed with spotted owls for territory and resources, and have been observed fighting with spotted owls.  Ashlee’s master’s research at Oregon State aims to quantify the stress experienced by spotted owls.

Northern spotted owl. Photo courtesy Ashlee Mikkelsen.

When birds experience stress, their bodies respond by releasing larger-than-usual quantities of the hormone corticosterone. Similar to cortisol in humans, corticosterone is always present, but having levels that are very high or that are very low is associated with poor health outcomes. It used to be that in order to measure the physical stress response of a bird, researchers had to take a blood sample. The problem with this is that the process of taking a blood sample itself is a source of stress for the bird. Recently, however, a new technique was introduced based on the fact that corticosterone is also present in feathers. Being able to use feathers is a distinct advantage: birds are constantly dropping feathers, so collecting feathers is fairly non-invasive, and importantly, similar to the benefits of measuring cortisol in hair, feather corticosterone measurements show the average level of the hormone over a long period, rather than just the instant that the feather is collected.

Ashlee banding a juvenile northern spotted owl. Photo courtesy Ashlee Mikkelsen

Ashlee banding a juvenile northern spotted owl. Photo courtesy Ashlee Mikkelsen

Working with professor Katie Dugger (who, incidentally, was Ashlee’s supervisor in the owl-monitoring field crew for the two years prior to beginning graduate school), Ashlee is analyzing a collection of feathers that spans over a 30-year time period. Measuring corticosterone levels in feathers is a high-tech process involving organic chemistry and radioactive isotopes. Although there are many complications that need to be accounted for, tracking the levels of corticosterone in these feathers gives Ashlee insight into the impact of stressors such as environmental degradation and competition with barred owls. Because the data spans so many years, she is able to examine the average stress in spotted owls over periods of change in the populations of barred owls. Ashlee’s data shows a strong response in corticosterone in spotted owls when the number of barred owls in the neighborhood goes up. This supports the view that spotted owls’ woes are not just due to habitat loss, but also due to competition with barred owls.

To hear more about Ashlee’s path to OSU, experiences in research, and of course about northern spotted owls, tune in Sunday, February 16th at 7 PM on KBVR 88.7 FM, live stream the show at http://www.orangemedianetwork.com/kbvr_fm/, or download our
podcast on iTunes!

 

Saving the blue whales of the South Taranaki Bight

A blue whale engulfs a patch of krill. Drone piloted by Todd Chandler.

Until a worldwide ban took effect in 1986, whaling and the production whale products, were leading to a decline in whale populations. Despite a greater global awareness about the importance of protecting our oceans, conflicts still exist between conservation efforts and industry.

This week’s guest, Dawn Barlow, studies the anthropogenic effects on blue whales (Balaenoptera musculus) – the largest known animal to have ever existed! Dawn is a first year PhD student in the Department of Fisheries and Wildlife’s Geospatial Ecology of Marine Megafauna (GEMM) Labwith Dr. Leigh Torres – the same lab where she completed her Master’s degree in 2018.

A blue whale mother and calf surface near Cape Farewell, New Zealand. Photo by Dawn Barlow.

Discovery of new whale population… and problem

Through her Master’s work, Dawn and her colleagues were able to document a genetically distinct population of about 700 blue whalesin the South Taranaki Bight (STB) – a region located between the north and south islands of New Zealand. The STB is not only an important region for the blue whales; however, it is also heavily used by industry, with active oil and gas extraction, seismic surveying, shipping traffic, and proposed seafloor mining. The need for a marine sanctuary in this area is eminent for the longevity of this whale population, but a compromise must be reached with the government and stakeholders. Furthermore, defining a sanctuary area in a dynamic system is not as simple as drawing a line in the sand.

Data collection Down Under

A pair of blue whales surface in New Zealand’s South Taranaki Bight region. Photo by Leigh Torres.

For her PhD research, Dawn will be continuing work with this same population of whales to get a better understanding of the ecological factors that influence where the blue whales are distributed. So far, three data collection trips have been conducted to gather some of this information. These ship-based trips have collected huge amounts of data using a myriad of equipment and techniques.

Echosounder data is collected using a transducer, which hangs off the boat and sends two pings per second producing measurements from the bounce back that can be used to map out krill aggregations – the blue whale’s primary food source. Conductivity, Temperature, Depth (CTD) casts are used to collect temperature and salinity pressure measurements to determine depth. Wind measurements are also recorded, as this generates upwelling. Photography and videography from the ship deck and via drones are used for identification of individuals whales with their skin providing the equivalent uniqueness as a human fingerprint. Satellite imaging is also used to record sea temperatures and chlorophyll levels. Lastly – and my personal favorite – darts shot from a smaller inflatable boat at close-range are used to collect skin and blubber samples for downstream genetic, stable isotope, and hormone analysis. Opportunistic sampling of fecal matter (i.e. if a whale poops) can also be used for genetic and hormone analysis.

Approaching a blue whale for photo-identification and biopsy sampling. Photo by Kristin Hodge.

Dawn participated in the 2017 field season and also went in July 2018 to disseminate findings to stakeholders. Now she is tasked with sifting through the data to correlate the oceanography with acoustic data, satellite imagery and presence of krill. Preliminary results suggest that the blue whales seem to appear where krill aggregate. Through habitat modeling on an ecosystem scale, Dawn hopes to be able to predict on a seasonal scale where the krill – and therefore, blue whales – will be, allowing for informed, science-based conservation and management decisions to be made.

Finding a passion for conservation biology

Dawn Barlow on the flying bridge of the research vessel during fieldwork in New Zealand. Photo by Kristin Hodge.

Growing up in Northern California near the ocean has always inspired Dawn to pursue a career in marine science. Dawn received dual bachelor’s degrees in Organismal Biology and Environmental Policy at Pitzer College in Claremont, California, where she recognized the need to build a bridge between biology and its translation to conservation policy. Knowing she wanted to get hands-on experience in marine mammal research, Dawn sought out and pursued opportunities through the MARMAM listserv, which landed her two undergraduate internships: one studying bottlenose dolphins in Australia and another in Alaska with humpback whales. These internships allowed Dawn to realize her desire to continue research through a graduate program at Oregon State University, where she has already completed her Master’s degree in Wildlife Science. After completing her PhD, Dawn plans to continue conducting conservation research.

Join us on Sunday, February 10 at 7 PM on KBVR Corvallis 88.7 FM or stream live to learn more about Dawn’s adventures Down Under, journey to graduate school, and answer to the age-old question: what does whale poop look like?

Kayaks and Computers: the Gray Whale Research Essentials

Throughout the year, looking out from the Oregon coast, you can often spot gray whales with the naked eye. Behind the magic and mystery of these massive creatures are teams of researchers tracking their migration and studying their diet.

Lisa Hildebrand is a 1st year Master’s student in Wildlife Science working with Dr. Leigh Torres within the College of Agriculture. Lisa studies geospatial ecology of marine megafauna, meaning that her research focuses on the feeding and movement through time and space of sea creatures larger than most fish, including large sea birds, seals, dolphins, and of course, the gray whales. To study such large animals in the ocean, Lisa manages a team that combines diverse technologies coupled with fine scale foraging ecology.

Gray whales feed on very small zooplankton suspended in shallow water. The whales don’t have teeth but instead have rows of baleen which look like a thick brush and act as a filter for water and sediment while letting in large quantities of zooplankton. In July and August, Lisa and her team of 4-5 people go out to Port Orford, Oregon. The team splits into two groups: a cliff team and a kayak team. From a cliff above their 1km2 sampling site, theodolites and computational programs are used to track whales by height and GPS location. Once a whale is spotted, team members kayak to this location and take water samples for analysis of zooplankton density, caloric content, species, and microplastic quantity. Lisa has taken over this ongoing project from a previous Master’s student, Florence Sullivan, and has data on the same research site and whales going back to 2015.

This research project provides opportunities for both undergraduates and high school level students to obtain first-hand field research experience. The students involved are able to take what they’ve heard in a classroom and apply it outdoors. In particular, Lisa is passionate about getting the students in the local Oregon coastal community involved in research on the whales that bring many tourists to their area.

To study the large gray whales, Lisa spends most of her time studying the small zooplankton that they eat. Zooplankton hide under kelp and it turns out, can be separated by populations that are pregnant, or varied in age or species. Gray whales may show preference for some feeding sites and/or types of zooplankton. Why do we care what a gray whale’s dietary preferences are? Plastic use and plastic pollution are rampant. Much of our plastic ends up in the oceans and photodegrade into microplastics small enough to be consumed by zooplankton. Since gray whales are the top predator for zooplankton and eat large qualities, these microplastics accumulate. Microplastic presence may differ between regions and species of zooplankton, which may relate back to whale preferences and migratory patterns. On the Oregon coastline, microplastic profiles of zooplankton have not yet been studied. As humans are also consuming large quantities of seafood, it is important to understand how microplastics are accumulating in these areas.

Lisa is from Germany and grew up in Vietnam and Singapore, but she was first inspired to pursue marine animal research as a career after a family trip to Svalbard, Norway during high school. Before obtaining her undergraduate degree in Marine Zoology from Newcastle University in England, Lisa took two years off from schooling and completed two internships: one with bottlenose dolphin sanctuary research institute in Italy and Spain, and one at a seal research facility in Germany. Now that she’s settled in Oregon for now, Lisa is enjoying the nature and in her free time loves hiking and skiing.

To learn more you can check out GEMM Lab website , the GEMM Lab blog and Lisa’s Twitter, @lisahildy95

To hear more about Lisa’s research, tune in Sunday, January 20th at 7 PM on KBVR 88.7 FM, live stream the show at http://www.orangemedianetwork.com/kbvr_fm/, or download our podcast on iTunes!

Core Strategies for Conservation of Greater Sage-Grouse

Greater sage-grouse (GRSG) is a North American bird species that nests exclusively in sagebrush habitat. In the last century, natural populations of this species have significantly declined largely due to human influenced habitat loss and fragmentation. This has prompted multiple petitions to the U.S. Fish and Wildlife Service (USFWS) to list GRSG under the Endangered Species Act (ESA), which would require mandatory restrictions on critical sagebrush habitat. This means that land managers of sagebrush areas would face land use restrictions for natural resource extraction and development, the bulk of the economy in Wyoming.

Wyoming Basin study site with associated GRSG Core Areas in blue. These Core Areas were designated as part of the GRSG Core Area Protection Act, Wyoming’s GRSG conservation policy aimed at protecting at least 67% of male GRSG attending leks. This policy is focused on directing development outside of these areas by setting strict conservation measures inside the Core Areas. Overall, the policy has remained effective in protecting at least 2/3 of GRSG habitat and has been identified as having the highest conservation value to maintaining sustainable GRSG populations.

 

Scent station and associated trail camera set-up in Natrona County, WY. Scent stations were randomly placed throughout the study site along roads and stratified between Core and Non-Core Areas. Mammalian predators are known to use roads for easy travel. These scent stations will help gather occupancy data of mammalian predators (Photo Credit: Eliana Moustakas).

Wyoming is a stronghold for GRSG, with the most birds, the most leks (male mating display grounds), and the largest contiguous sagebrush habitat in North America. Since GRSG declines have led to its possible endangered listing, Wyoming Governor Dave Freudenthal launched an effort in 2007 to develop stronger policies for GRSG that would protect the species and its habitat while also sustaining the state’s economy. A public forum followed, including representatives from state and federal agencies, non-governmental organizations, and industries, and in 2008 a conservation policy called the Greater Sage-Grouse Core Area Protection Strategy was developed to maintain and restore suitable habitat and active breeding GRSG pairs. The plan aims to protect at least 67% of male GRSG attending leks, and is focused on directing development outside of Core Areas by setting strict conservation measures inside Core Areas. By protecting sagebrush habitat and allowing development and mining in Non-Core Areas, Wyoming can continue to expand its natural resource economy and play a critical role in GRSG conservation.

In 2010, the USFWS concluded that GRSG were warranted protection but left them off the ESA list because threats were moderate and did not occur equally across their range. The status of GRSG was reevaluated in 2015 and the USFWS determined that GRSG did not warrant protection, claiming that the Core Area Strategy was sound framework for a policy by which to conserve GRSG in WY. However, recent monitoring of GRSG has shown that populations are still in decline in some Core Areas and in populations across their range. Our guest this week, Claire Revekant, a second year Master’s student in the Department of Animal and Rangeland Science, is trying to understand if avian and mammalian predator abundance differs between Core and Non-Core Areas.

Golden eagle using a utility pole to perch. Raptors and corvids are known to use  structures to perch and nest.

 

Working under Dr. Jonathan Dinkins, Claire estimates associations between human influence areas and habitat variables on the abundance of predatory birds and occupancy of mammalian predators. For example, raptors and corvids have been documented to perch and nest on fences and other human structures, and roads have been found to be used as travel paths for mammalian predators. Claire’s hypothesis is that predatory animals will be higher in Non-Core Areas where human-influenced environments serves as areas of food subsidies. Identifying areas of predator abundance and relating those areas to human features and habitat variables may help policy makers prioritize plans to mitigate human influence and protect sagebrush habitat.

Badger captured by trail camera at scent station in Lincoln County.

While her research is focused on predators of GRSG, Claire’s work for GRSG conservation contributes to the conservation of other sagebrush-obligate species (species that relay on sagebrush for all or some parts of their life cycle). By protecting the ecosystem for one “umbrella” species, other species may also benefit. Throughout her career as a wildlife biologist, Claire has been involved with numerous projects where she has handled and monitored several species. From learning to band raptors as a child to monitoring seabird productivity as an intern at the Monomoy National Wildlife Refuge, Claire has developed a passion for research. She told us that she can’t remember a time when she had a different dream job. Tune in tonight Sunday November, 11 at 7 to hear more about Claire’s research and her journey to graduate school on 88.7 FM KBVR Corvallis, or stream the show live.

Stream ecosystems and a changing climate

Examining the effect of climate change on stream ecosystems

Oak Creek near McDonald Dunn research lab. The salamander and trout in the experiments were collected along this stretch of creek.

As a first year Master’s student in the lab of Ivan Arismendi, Francisco Pickens studies how the changing, warming climate impacts animals inhabiting stream ecosystems. A major component of stream ecosystem health is rainfall. In examining and predicting the effects of climate change on rainfall, it is important to consider not only the amount of rainfall, but also the timing of rainfall. Although a stream may receive a consistent amount of rain, the duration of the rainy season is projected to shrink, leading to higher flows earlier in the year and a shift in the timing of the lowest water depth. Currently, low flow and peak summer temperature are separated by time. With the shortening and early arrival of the rainy season, it is more likely that low flow and peak summer temperature will coincide.

A curious trout in one of the experimental tanks.

Francisco is trying to determine how the convergence of these two events will impact the animals inhabiting streams. This is an important question because the animals found in streams are ectothermic, meaning that they rely on their surrounding environment to regulate their body temperature. Synchronization of the peak summer temperature with the lowest level of water flow could raise the temperature of the water, profoundly impacting the physiology of the animals living in these streams.

 

 

How to study animals in stream ecosystems?

Salamander in its terrestrial stage.

Using a simulated stream environment in a controlled lab setting, Francisco studies how temperature and low water depth impact the physiology and behavior of two abundant stream species – cutthroat trout and the pacific giant salamander. Francisco controls the water temperature and depth, with depth serving as a proxy for stream water level.

Blood glucose level serves as the experimental readout for assessing physiological stress because elevated blood glucose is an indicator of stress. Francisco also studies the animals’ behavior in response to changing conditions. Increased speed, distance traveled, and aggressiveness are all indicators of stress. Francisco analyzes their behavior by tracking their movement through video. Manual frame-by-frame video analysis is time consuming for a single researcher, but lends itself well to automation by computer. Francisco is in the process of implementing a computer vision-based tool to track the animals’ movement automatically.

The crew that assisted in helping collect the animals: From left to right: Chris Flora (undergraduate), Lauren Zatkos (Master’s student), Ivan Arismendi (PI).

Why OSU?

Originally from a small town in Washington state, Francisco grew up in a logging community near the woods. He knew he wanted to pursue a career involving wild animals and fishing, with the opportunity to work outside. Francisco came to OSU’s Department of Fisheries and Wildlife for his undergraduate studies. As an undergrad, Francisco had the opportunity to explore research through the NSF REU program while working on a project related to algae in the lab of Brooke Penaluna. After he finishes his Master’s degree at OSU, Francisco would like to continue working as a data scientist in a federal or state agency.

Tune in on Sunday, June 24th at 7pm PST on KBVR Corvallis 88.7 FM, or listen live at kbvr.com/listen.  Also, check us out on Apple Podcasts!