Tag Archives: Ecology

Aquatic Invertebrates: Why You Should Give a Dam

Rivers are ecosystems that attract and maintain a diversity of organisms. Fish, birds, mammals, plants, and invertebrates live in and around rivers. Have you considered what services these groups of organisms provide to the river ecosystem? For example, river invertebrates provide numerous ecosystem services:

Dragonfly larvae caught in in the waters of a small stream flowing into the Grand Canyon.

  • Insects and mussels improve water quality by fixing nutrients, such as those from agricultural runoff.
  • River invertebrates are food resources for fish, bats, birds, and other terrestrial organisms.
  • Grazing insects can control and/or stimulate algal growth.
  • Mussels can help to stabilize the bed of the river.

High school students are the best helpers for sampling aquatic insects!

And the list continues. These invertebrates have adapted to the native conditions of their river ecosystem, and major disturbances, such as a change in the flow of a river from a dam, can change the community of organisms downstream. If dams decrease the diversity of invertebrates downstream, then they may also decrease the diversity of ecosystem services offered by the invertebrate community.

Our guest this week, Erin Abernethy PhD candidate from the department of Integrative Biology, is investigating the community structure (or the number of species and the number of individuals of each species) of freshwater aquatic invertebrates downstream of dams. Specifically, Erin wants to know if invertebrate communities near dams of the Colorado River are different than those downstream, and which factors of dams of the Southwest US affect invertebrate communities.

Getting to field sites in the Grand Canyon is easiest by raft! It’s a pretty float, too!

Erin’s dissertation also has a component of population genetics, which examines the connectivity of populations of mayflies,populations of caddisflies, and populations of water striders. The outcomes of Erin’s research could inform policy around dam operation and the maintenance of aquatic invertebrate communities near dams.

“One must dress for sampling success in the Grand Canyon!” said this week’s guest, Erin Abernethy, who is pictured here.

Growing up, Erin participated in many outdoor activities with her parents, who are biologists. She became interested in how dams effect ecology, specifically fresh water mussels, doing undergraduate research at Appalachian State University. After undergrad, Erin completed a Master’s in Ecology from University of Georgia. She was investigating the foraging behavior of animals in Hawaii. This involved depositing animal carcasses and monitoring foraging visitors. Check out Erin’s blog for photos of these animals foraging at night! Erin decided to keep going in academia after being awarded a Graduate Research Fellowship, which landed her a position in David Lytle’s lab here at Oregon State. After she completes her PhD, Erin is interested in working for an agency or a nonprofit as an expert in freshwater ecology and the maintenance of biodiversity in freshwater ecosystems.

 

Tune in at 7 pm this Sunday February, 25 to hear more about Erin’s research and journey to graduate school. Not a local listener? Stream the show live.

Horse Farms to Tree Farms: Studying the Relationship Between Land Management and Biodiversity

If you wander forests of the Oregon Coast Range you might encounter a strange sight: exclosures made of timber and steel-braided wire, standing in a clear-cut forest. These exclosures, which stand 100-feet long, 50-feet wide and 8-feet high, are the research and work of Thomas Stokely, a PhD candidate in the department of Forest Ecosystems & Society in the College of Forestry. The exclosures were constructed to study the impact of deer and elk grazing on tree growth, and to address a larger research question in forestry management: What does intensive forest management mean for biodiversity?

Completion of exclosure construction in the Oregon Coast Range

Completion of exclosure construction in Oregon Coast Range

To study the impact of deer and elk on commercial tree growth, Thomas constructed constructed 28 stands in which a team of researchers manipulated the intensity of herbicide spray treatments in each area (non-sprayed, light, moderate and intensive herbicide treatments). For six years, under the direction of his adviser Matthew Betts, Thomas and has measured plant communities, arthropods, herbivory and plantation development inside these exclosures and in open plots where wildlife is allowed free access.

Thomas Stokely cutting fence rows through logging slash and large stumps to construct wildlife exclosures

PhD student, Thomas Stokely cutting fence rows through logging slash and large stumps to construct wildlife exclosures

The exclosure research in the Oregon Coast Range relates to Thomas’s goals as a scientist who’s invested in understanding how industry impacts biodiversity. “As the world population grows, we need more resources,” he said. “We want to value the product, but we also value biodiversity and wildlife habitat. Is there a way we can manage for both timber production and wildlife habitat? If so, what role do biodiversity and wildlife play in the management of natural resources? If management alters biodiversity or excludes wildlife, what are the implications for ecosystem functioning?” These are questions that continue to drive his research and his career path.

Mature Roosevelt elk bulls browsing through a plantation with exclosure in the background

Mature Roosevelt elk bulls browsing through a plantation with exclosure in the background

Thomas has been interested in plant-animal interactions and the environment since he was a child. Growing up on a horse farm in southwest Missouri, he watched horses grazing and wondered about their relationship with the habitat in and around the farm. He first considered studying the policy side of humanity’s relationship with the natural world, but political science wasn’t a good fit—he wanted to pursue a more hands-on approach to studying biodiversity. After reading about the reintroduction of wolves in Yellowstone, he knew he wanted to work directly with land and habitat management. He earned a BS in environmental science at University of Missouri before coming to Oregon State. Upon completing his PhD, Thomas plans to work in applied ecology where he hopes to use science to guide land management and conservancy practices.

Tune in to hear our conversation with Thomas Stokely on Sunday, November 13th at 7:00 pm on 88.7 FM KBVR Corvallis or listen live online

Paul does it all: Is there hope for the amphibian taxa?

Everyday there is a constant battle between healthy immune systems and parasites trying to harass our bodies. In the case of buffalos in South Africa they cannot simultaneously fight off a tuberculosis infection and a parasitic worm. Their immune system has to choose which of the adversaries it will fight; this decision has consequences for the individual and the health of the entire population of buffalos it encounters. This situation is not unlike those for humans. We are not fighting one immunological disease at a time, but many at once and they can interact to influence how we feel. Our guest this evening specializes in disease ecology, which focuses on how the spread of pathogens interacts with humans and non-human organisms.

Paul while working as the Ezenwa Lab manager at the University of Georgia

Paul while working as the Ezenwa Lab manager at the University of Georgia

Paul Snyder has worked on tiny ticks in New York to wild buffalo in South Africa, but he’s had a very colorful life before beginning his studies at OSU. Even though he loved everything science and technology growing up, there was limited exposure to those fields in high school and he never thought of being a scientist as a career path. To put things in perspective, he wasn’t allowed to buy any video games growing up; instead he programmed his first working computer game at the ripe age of 6, yes six, years old! Paul continued his illustrious career as a 13-year old paperboy, then burger flipper, and eventually working his way up through the ranks to the manger of a Toys R Us store. He realized he wanted to focus on science and pursued his schooling at University of South Florida doing research on the interaction of parasites and tadpoles, then New York counting ticks, and finally University of Georgia as a lab manager. Oh yeah, somewhere in-between he successfully mastered the bass guitar with his band mates and learned how to program virtual reality simulations, but I digress.

In his downtime Paul works on virtual reality apps for us to enjoy

In his downtime Paul works on virtual reality apps for us to enjoy

Back in the world of science, Paul is working with Dr. Blaustein’s Integrative Biology lab group in the College of Science that he first became aware of from his work with South African buffalo’s. Rather than beginning his disease ecology research with human trials, Paul is focusing on the #1 declining vertebrate taxa in the world. Amphibians have been sharply declining since the 1980’s and there have been no shortage of guesses, but sadly few answers as to why this is happening. Paul’s current project has identified a species-virus interaction (e.g. the number of species present impacts how the infection spreads). But Paul’s real interest and ongoing research lies in the very young field of ecoimmunology: how do the immune systems of organisms change over time in response to the environment they experience.

You’ll have to tune in to hear how he plans to rectify the molecular-scale view of immunology, with the large-scale controls from the environment. You can listen tonight September 18th 2016 at 7PM on the radio at 88.7FM KBVR Corvallis, or stream live at 7PM.

Are You Listening? For Whale’s Sake, Keep it Down!

Our guest tomorrow night, Selene Fregosi PhD student in Fisheries and Wildlife, investigates noises produced by marine mammals and in particular, whales. Selene employs an under water microphone to record the bioacoustics produced by marine mammals over large spatial and temporal scales. Attached to remote controlled marine gliders, these microphones can record bioacoustics of marine mammals, some of which produce sounds of inaudible frequencies. Marine gliders limit the time and expense of whale monitoring from the deck of a marine vessel. This cost effective alternative allows Selene to collect oceanographic measurements like temperature and salinity and her audio recordings remotely through satellite transmitted programing. Selene’s explorations through her project will provide information about the effectiveness of this technology for future research with marine mammals.

Selene getting the glider ready.

Selene getting the glider ready with the help of Alex Turpin.

In addition to the practical aspects of this research, Selene is interested in how noise pollution from ships, submarines, and other vessels affects the behavior of charismatic mega fauna. By examining the sound spectra of an audio recording, Selene can identify each species by their characteristic sound patterns. After deciphering bioacoustics obtained from the microphoned-gliders, Selene can understand whale behavior during different times of year or different locations around the world. In fact, some of Selene’s recordings are the first ever to record whale behavior and movement off the coast of Guam!

Characteristic sound pattern of a beaked whale.

Characteristic sound pattern of a beaked whale.

Selene hopes that in the future, her work will aid the conservation of whales and other marine mammals. Deciphering bioacoustics can allow for the identification of when and where specific species are breeding, and conservationists can then work to reduce noise pollution. As our oceans become noisier from human activities, Selene’s research could provide accurate and specific information to limit disruption of crucial population maintenance and growth.

Learn more about Selene’s and other interesting research from the Klinck lab at OSU by visiting their blog.

Join us Sunday, November 22 at 7 pm to hear more about Selene’s research and her unique journey to graduate school. Tune in to KBVR Corvallis 88.7 FM or stream the show live!