Tag Archives: aquatic invertebrates

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.

Go With The Flow

If you get the chance to meet Emily Khazan, you’ll probably learn a thing or two about damselflies. You can think of them as smaller versions of dragonflies whose wings can fold back

Emily attempting to collect ants off of baited trees in Costa Rica

Emily attempting to collect ants off of baited trees in Costa Rica

when they perch. They need bodies of water to breed and live, and sometimes, water caught in the leaves of a plant is all that’s needed for survival. For her Masters degree, she worked with damselflies that lived in old growth forests in Costa Rica. She would wade through thick underbrush, collecting data, trying to understand how damselflies were affected by a highly impacted landscape throughout a biological corridor that was designed for restoration of habitat for a large-bodied, strong-flying bird.


These days, you’ll find her stooped over the bank of a river in the desert, collecting the various insect inhabitants that live there. Working in the David Lytle lab, she wants to understand how these aquatic invertebrate communities are affected by climate change by seeing how they respond to the changing river flow. Why does it matter? Because aquatic invertebrates not only serve as a food source for fish, and a good indicator for water quality, but because our world is interconnected, biodiversity matters.


One of Emily's current study sites: the lower Salt river outside of Phoenix, AZ

One of Emily’s current study sites: the lower Salt river outside of Phoenix, AZ

So, how does one go from research in the tropics to the arid lands of the American southwest? For Emily, its a story where she continuously reinvents herself as she moves across the landscape. This Sunday, you can hear her journey from her first ecology course at the University of Michigan, to persevering through an underfunded Masters degree fueled by her weird love of damselflies and their environment, to leading a research station in Costa Rica, and finally coming to OSU to study aquatic invertebrates.

Tune in Sunday, June 12, 2016 at 7PM PST on KBVR 88.7FM or stream live at http://kbvr.com/listen

View of the Costa Rican coast line from the Caño Palma Biological Station (http://www.coterc.org/)