Category Archives: Marine Resource Management Program

Rethinking oyster reef restoration and coastal community resilience: The use of biomimicry and outreach to offset the growing risk of invasive species

“I like to think of them as the corals of estuaries,” says Megan Considine as she describes the role that oysters play in coastal systems all over the world. Megan is a first-year Marine Resource Management Masters student who is working on a project to map the distribution of an invasive mud worm (Polydora websteri) that infects native shellfish such as the commercially grown Pacific oyster (Crassostrea gigas) and wild populations of Olympia oysters (Ostrea lurida).

Oyster transplant project in the Lynnhaven River, a tributary to the Chesapeake Bay where Megan worked prior to coming to OSU. Photo courtesy of Megan Considine.

Megan explains that these tiny worms don’t make the oyster meat inedible, as infected populations can still be harvested and sold for canning, but they do become unmarketable on the half shell. This is because the worms crawl between the inner shell surfaces, and the oyster then grows new shell material over it to wall off the invader. The worm then deposits muddy material or debris into the shell pocket and essentially creates a blister. Although these blisters are not known to negatively impact the oysters themselves, they are not exactly aesthetically pleasing to the consumer. This is what is really hurting the multi-million dollar industry and the main reason stakeholders from Alaska, Washington, Oregon and California are all working together to detect and prevent further spread of the worms. 

A Pacific oyster infected by the invasive mudworm, showing blisters that have been opened up to try and extract the worm. Photo courtesy of Megan Considine.

Dr. Steve Rumrill is the Shellfish Program Leader at the Oregon Department of Fish and Wildlife (ODFW) and as courtesy faculty of Hatfield Marine Science Center is Megan’s primary advisor. Working with ODFW, Megan visits shellfish farms located in estuaries along the Oregon coast and picks up oysters which are inspected for worms. If found, samples are then sent to a lab in Washington for genetic analysis to confirm infestation. Megan says that farmers may not even know their oysters are infected and she hopes to expand her work beyond just ecological sampling to outreach and mitigating an emergent problem.

“I want to create an education piece in Spanish and English, so that farmers can be aware of when their oysters are infected.”

Megan’s passion for education goes far beyond aquaculture. Getting back to her coral analogy, oysters are not just important to aquaculture here in the Pacific Northwest. Ecologically, they are incredibly valuable wherever they occur both when living, for example, filtering the water column, but also after they die. Their calcium carbonate shells provide the foundational habitat that supports an incredible diversity of estuarine life. 

For a long time in oyster restoration efforts, it’s been understood that substrate is a primary limiting factor in supporting this reef-building capacity of oysters. According to Megan, in the PNW, they were just completely overharvested during the Gold Rush era. In addition to her work on invasive mud worms in oyster farms, Megan is also a part of efforts to restore natural oyster populations in Oregon, specifically at Yaquina Head. And this is an area of research Megan has been passionate about for some time. 

Megan getting ready to snorkel assist with coral restoration in the Florida Keys working with Mote Marine Laboratory. Photo courtesy of Megan Considine.

Originally from Virginia Beach, Megan recalls her time as an elementary school student being tasked along with her classmates to monitor the growth of a bag of oysters donated by a local non-profit. Along with studying their entrusted specimens, she says that they would also engage in other activities about estuarine ecology surrounding oysters in the Chesapeake Bay. This hands-on experience would come full circle when after completing her undergraduate studies at the University of South Carolina, Megan had the opportunity to intern with the same organization, Oyster Reef Keepers, that sponsored the oyster education program in several schools, leading kids through many of the same activities that sparked her early fascination with estuary ecosystems and marine science.  

Although a more well-known issue on the East coast, Megan explains that oyster habitat degradation is a world-wide problem and she came to Oregon State to expand her knowledge of its effects in other places. She says that oyster restoration hasn’t had as much momentum here in the West because aquaculture has been the focus, but it’s gaining traction. Concern over threats like climate change to coastal ecosystems have supported this trend. Although oysters are  less sensitive to climate change impacts like ocean acidification than corals are known to be, it still may compromise their ability to cope with other direct threats, such as invasive species. 

At Yaquina Head, Megan is working with an artist from the East coast named Evelyn Tickle who makes concrete tiles to be used in oyster reef restoration that are designed to mimic natural oyster beds. These one square foot tiles differ from the cinder block structures that have been used to provide substrate for the oysters to grow on in the past by providing a more complex structure made of compounds like calcium carbonate. Overall, the tiles give oysters a better chance to establish amidst other stressors. 

Megan has been so inspired by Evelyn’s work that she has begun working with two other OSU students, Chad Sullivan and Nicolás Gómez-Andújar, to develop other biomimicry concrete structures for future restoration efforts that support the erosion and storm mitigation services that both oysters and corals provide to coastal systems. They are calling themselves the Urban Reef Lab

Megan on one of many coastal trips taken since Megan moved to Oregon; exploring the West coast is one of her favorite pastime’s. Photo courtesy of Megan Considine.

“The idea is that instead of using simple and smooth breakwater structures or sea walls, we can incorporate textures and shapes that are designed for specific organisms. So, working with nature rather than against. For instance, if the goal is oyster settlement we would use the appropriate texture such as crevices and pits. The designs can also be used as hard substrate for coral outplants or for oyster restoration efforts, like the Yaquina Bay project.”

To learn more about Megan’s research and outreach goals beyond her graduate work, tune in to KBVR 88.7 FM or stream online April 19, 2020 at 7 P.M. 

Working with Dungeness crab fishermen to get a ‘sense’ of low-oxygen conditions off the Oregon coast

Linus tidepooling at Yaquina Head, Oregon Coast.

Linus Stoltz is a graduate student in the Marine Resource Management Master’s Program through the College of Earth Ocean and Atmospheric Sciences, co-advised by Dr. Kipp Shearman and Dr. Francis Chan. Only in his second term, Linus is already diving in to a project that means a lot to Oregon coastal communities.

Dungeness crab is the most profitable state-managed fishery in Oregon, generating $66.7 million dollars in commercial sales over the 2018-2019 season alone. However, an increasing threat to this valuable industry that has caused significant harvest reductions in recent years: hypoxia. Hypoxia refers to low-oxygen conditions in the ocean that have been recorded as occurring more frequently off the Oregon Coast and elsewhere in the Pacific Northwest, where Dungeness crab fishing is a major activity. In some parts of the ocean, such as the Gulf Coast, these conditions are triggered by pollution which causes overproduction of algae, followed by excess decomposition. However, here, it’s more complicated. These conditions are generated by offshore wind- driven movement of cold, nutrient-rich but oxygen-poor deep water across the continental shelf, toward the coast.

This process of ‘upwelling’ (see figure below) is a natural occurrence, but scientists speculate that climate change is making these events more frequent and their characteristics severe. As a Marine Biology major in his undergraduate studies at the University of North Carolina Wilmington, Linus admits that oceanography isn’t exactly in his “wheelhouse” but it doesn’t take an oceanographer to understand that atmospheric conditions are strongly tied to ocean circulation patterns. Referring to graphic representations of Northwest wind stress and dissolved oxygen concentrations, he says “they’re pretty well correlated.” Normally, the offshore winds that drive upwelling are counteracted by a shifting of wind patterns that ultimately allow them to mix sufficiently and re-oxygenate. But the reality is that this is happening less and less frequently.

The process of ‘upwelling’ off the West Coast. Source. www.noaa.gov

What does hypoxia mean for Dungeness crabs? Linus describes the events like waves of low-oxygen water moving slowly across the seafloor. As bottom-dwelling organisms that depend on dissolved oxygen to breathe, if conditions are severe enough or persist long enough, they’ll die. More and more instances of crab fishermen pulling up their gear full of dead crabs prompted them to reach out to scientists for help. Oregon Department of Fish and Wildlife (ODFW) biologists and researchers at Oregon State University (OSU) have been working together since 2002 to try and find answers. Check out this video by ODFW to see real-time footage of a hypoxic wave as it flows over a Dungeness crab pot in 2017.

While we are beginning to understand the bigger picture of the oceanographic conditions that result in hypoxia, Linus explains that we don’t have any models that predict this ‘wave’ on a finer scale. He describes the ocean as patchy, where conditions just a thousand yards away from where a fisherman may have set his or her pots may be completely different. The ultimate goal of his research is to be able to predict these conditions and inform management decisions such as seasonal and/or spatial closures.

The roughly two-foot long Sexton oxygen sensor seen above will be attached to an individual crab pot that will transmit data via Bluetooth to the Deck Data Hub which will then relay the information to a receiver on the OSU campus.

But even more important to fisherman now, the project will also provide ‘in situ’ information fisherman can use to make critical decisions while they’re out there. To achieve this, Linus will be equipping fishermen with sensors to be deployed by Dungeness crab fishermen through the season to collect data on dissolved oxygen. The data recorded by the sensors can be seen immediately by fishermen when they retrieve their pots and will also be automatically transferred via Bluetooth to a box on deck which will ultimately transmit to a receiver on the OSU campus. The hope is to capture the variability in oxygen conditions, while minimizing their impact on fishing operations.

Linus tagging red drum in Hancock Creek when he worked for North Carolina Division of Marine Fisheries (NCDMF).

Before coming to OSU, Linus spent time as an observer for the North Carolina Division of Marine Fisheries testing by-catch reduction technology in the shrimp trawling industry, an experience he recounts as “character-building to say the least.” In other words, Linus knows how important it is to streamline the process if he wants to get any cooperation from fishermen and collecting data can’t be in the way or slow them down. A stark contrast, however, between the interactions between fisherman and researchers on the East Coast to Oregon is that this relationship is more than just cooperative, it’s a collaboration. Fishermen here trust scientists, but at the same time the researchers recognize that fishermen are out there more and are the ones who see changes first-hand.

For Linus, this project represents one of just about any marine science topic he’s excited to be involved in. To learn more about Linus’s journey from SCUBA diving in a cold lake in Ohio as a ten-year old to working as an underwater technician monitoring artificial reefs off the coast of North Carolina, tune in to KBVR 88.7 FM or online February 23, 2020 at 7 P.M.