Ocean Acidification

The distilled water was colored by the red cabbage that had been boiled in it. Judging by Kylie, and the reaction of the other students in her fifth-grade class at Blaine Elementary School, the smell of the bubbling water was off-putting.

But the cabbage water was there to help the students see what happens when carbon dioxide – from their breath as they blow into the straw – dissolves in the small amount of water. It makes acid, which turns the liquid’s color in their cups from purple to pink.

At another station, students dipped litmus paper into common household solutions such as distilled water, baking soda and water, lemon juice and dissolved Tums, then compared them to a pH chart showing different colors for levels that range from acid to neutral to base. (The pH scale describes the range of chemicals, with acid and base as opposites.)

At a third station, students learned about the anatomy of oysters and how they contribute to the ecosystem, such as their ability to filter and clean water.

Ocean acidification is caused primarily by oceans absorbing excess carbon dioxide released into the atmosphere through burning fossil fuels. It is altering ocean chemistry and making sea water more acidic – endangering sea life, which also threatens commercial oyster operations, such as those in Blaine’s Drayton Harbor, and the seafood industry in Washington state.

Oceans are 30 percent more acidic than they were before the start of the Industrial Revolution roughly 200 years ago, according to a 2010 National Research Council report.

On Wednesday, April 17, the 25 students in teacher John Dennison’s class learned where carbon dioxide comes from – the students when they breathe out, smokestacks when energy is burned, dead material decaying, out of the tailpipes of cars – and the impact of the ocean becoming more acidic.

“Acid does what, acid in the ocean?” asked Julie Hirsch, who was leading that day’s experiments, which are part of the Garden of the Salish Sea program launched by the nonprofit Puget Sound Restoration Fund.

Hirsch was focusing specifically on shellfish, including oysters.

“They can’t form their shells, can they?” Hirsch said to the students.

Nor can the diatoms, the algae that are a food source for oysters. Ocean acidification also destroys coral reefs, she told the students.

“We’re building on the whole food chain and what happens if organisms toward the bottom of the food chain can’t reproduce,” Hirsch said in an interview.

Garden of the Salish Sea is a pilot project in its second year that aims to teach students and the community about what they can do to keep watersheds in Whatcom County clean. It will reach 175 fifth-graders in Blaine this year. Hirsch developed the curriculum.

The segment on ocean acidification is new.

The environmental science curriculum focuses on shellfish – including field trips to the Drayton Harbor Community Oyster Farm in Blaine – to teach pollution prevention.

“It really is about educating the community, not just the kids,” Hirsch said.

That includes reaching out to adults through their children via the Salish Sea Pledge, which has steps people can take, including reducing carbon dioxide emissions, to keep the water clean and shellfish safe to eat. Those include turning off lights that aren’t being used, scooping their pet’s waste, and walking or riding instead of asking their parents for rides.

To fifth-grade teacher Dennison, it’s good that the students are “more aware of what impacts they could have on the environment.”

“This is something that’s a local environmental issue,” he said, referring as well to fecal coliform bacteria levels in the watershed that empties into Drayton Harbor.

In addition to the science piece, Dennison noted that the Salish Sea curriculum also teaches students about the “economic impacts of bad environmental choices.”

IF YOU GO

What: The community can drop in to see demonstrations related to shellfish and to learn about watershed-friendly practices.

When: 10 a.m. to 2 p.m. April 24, 26, and May 1.

Where: Blaine Harbor Boating Center, 235 Marine Drive.

Also: The public can take tours of the Drayton Harbor Community Oyster Farm aboard the walk-on ferry, the Plover, from 10 a.m. to 2 p.m. May 25. Meet at Gate 1 of Blaine Harbor, 235 Marine Drive.

Plover fare: Suggested donation of $5 for adults and $1 for children.

Learn more: Additional information about the Garden of the Salish Sea Curriculum is online at restorationfund.org/salishseacurriculum.

Kie Relyea, The Bellingham Herald, 18 April 2013. Article.