Aug. 29, 2017

A new video from Oregon Sea Grant shows how researchers are studying how nutrients from agricultural runoff and oceanic upwelling impact the growth of light-blocking algae on eelgrass in bays along the Oregon coast.

With funding from Oregon Sea Grant, they’re also studying how tiny herbivores, such as sea slugs and centipede-like isopods, might prevent eelgrass from being snuffed out by this algae. Additionally, they’re investigating whether these herbivores prefer to eat the native or invasive eelgrass in the bays.

In the six-minute video, Fiona Tomas Nash, a marine ecologist in the Department of Fisheries and Wildlife at Oregon State University, explains that eelgrass is important because it produces oxygen, reduces the impacts of waves, and provides habitat and food for waterfowl, baby fish and crabs.

“Nutrient pollution is one of the main causes of seagrass loss worldwide,” Tomas Nash said in the video. “And so we’re trying to understand if this is a problem in Oregon.”

She said the results of her research may benefit state and federal agencies that deal with food production, fisheries and water quality.

The research is taking place in four estuaries – Coos Bay, Yaquina, Netarts and Tillamook – to quantify how much seagrass there is and determine what aquatic grazers are present, Tomas Nash said.

“We’re doing experiments, both in the field and in the lab,” she said in the video, “where we add nutrients, and we also manipulate the presence or absence of these animals to see how these combinations of more nutrients and different animals can affect the amount of algae that there is and, therefore, the seagrass health.”

Partners in the project include the Oregon Department of Fish and Wildlife, the Environmental Protection Agency and the South Slough National Estuarine Research Reserve. 

The video was produced by Tiffany Woods and filmed and edited by Gustavo Garcia.

Photos of Tomas Nash and her work can be downloaded from this album on Oregon Sea Grant’s Flickr page.

More information about the research is on Oregon Sea Grant’s website.