Clams and climate change — new Alaska study examines the connections


Shellfish biologist Jacqueline Ramsay monitors ocean chemistry using a Burke-O-Lator at Alutiiq Pride Shellfish Hatchery. (Photo by Paula Dobbyn)

July fourth in Seward is known for its fireworks, festivities and the grueling Mt. Marathon race that draws elite athletes from around the world. But for a University of Alaska Fairbanks (UAF) graduate student, the holiday took on a whole different meaning this year.

“It was the first time I was able to successfully spawn razor clams in the lab,” said Marina Washburn, who is working on her master’s degree at UAF’s College of Fisheries and Ocean Sciences (CFOS). Her research is based out of Seward.
As locals and visitors watched a parade snake through downtown, Washburn stared into a bucket, her eyes wide as she observed new life forming at the bottom.

“We weren’t sure it was possible to spawn razor clams. My first attempt failed. When they finally hatched, I felt I could celebrate,” she said.

Washburn needed clam larvae to study how ocean acidification affects the shellfish. Razor clams have virtually disappeared on the eastern shores of Cook Inlet. Clam populations in Southcentral Alaska overall have declined since the late 1990s, according to University of Alaska researchers. It’s negatively affected people who clam for subsistence, recreation and commercial purposes.

As a fourth generation Alaskan, Washburn grew up razor clamming on the Kenai Peninsula. But officials shut down the harvest in 2015, citing severe population declines. It has remained closed ever since.

“My family and many others have a vested interest in bringing this species back,” Washburn said.

No one knows exactly what’s caused razor clams to crash to historically low levels. Theories include “heavy surf, habitat changes, environmental stressors and predation,” according to the Alaska Department of Fish and Game.  Another factor under consideration is ocean acidification (OA), the decline of seawater pH caused by the ocean absorbing too much carbon dioxide from sources including tailpipes and smokestacks.

Washburn is testing the extent to which razor clams are resilient or susceptible to an acidifying ocean.

She’s using a method pioneered by Amanda Kelley, a marine biology professor at CFOS and an ocean acidification expert.

With funding from Alaska Sea Grant, Kelley developed a protocol for exposing cockles and littlenecks to varying ocean chemistry conditions that mimic what’s happening in the ocean today as well as what can be expected in future decades. It’s the first study of its kind in the state, according to the proposal Kelley submitted for Sea Grant funding. Before the cockle and littleneck study, no experimental work had been done in Alaska on how native bivalves respond to ocean acidification, the professor said.

“We’re just at the very, very beginning point of understanding how Alaska species are going to respond to OA and more broadly ocean change,” said Kelley, standing before a row of white buckets containing seawater and tiny clams with coils of plastic tubing pumping in various levels of CO2

Paula Dobbyn, University of Alaska Fairbanks (via: Sea Grant Alaska), 13 September 2018. Press release.

  • Reset


OA-ICC Highlights

%d bloggers like this: