This story
first appeared in E
Magazine.
On most days, Bill Dewey can be found wearing waist-high waders and
inspecting Manila clams—the West Coast version of the littleneck—at his
Washington clam farm, Chuckanut Shellfish. Under an arrangement that’s unique to
the state, Dewey owns 32 acres of tidelands. Unlike land-based farms, he can
only harvest when the tide recedes, leaving over a mile of mudflats, and
shellfish, exposed. He gathers the clams with the help of a former tulip-bulb
harvesting machine that’s carried out aboard his boat, the Clamdango!
Working on the mudflats, often with his son and dog in tow, is the
fulfillment of a dream for Dewey, a shellfish farmer for more than 30 years who
is also the public policy and communications director for Taylor Shellfish
Company. Taylor’s operations—which include growing oysters, clams, mussels and
geoduck (giant clams whose necks can reach more than three feet long)—span some
1,900 acres of the same tidelands. All told, there are about 47,000 acres of
oceanic land that have that special designation in the state, and, he says,
“It’s fundamental as to why Washington leads the country in farmed shellfish
production. In other parts of country, you typically have to lease the land from
the state. Banks are less apt to loan money to businesses that have to
lease.”
Commercial shellfishing makes up the lion’s share—two-thirds—of the nation’s
aquaculture industry. So reports the National Oceanic and Atmospheric
Administration’s (NOAA’s)
Fisheries
Service which makes a case for boosting domestic seafood production, noting
that Americans eat a lot of seafood, and import 86% of it, creating a U.S.
seafood trade deficit that now exceeds $10.4 billion annually, second only to
oil when it comes to natural resources. In the Pacific Northwest, the shellfish
industry contributes $270 million per year to the regional economy and employs
more than 3,200 people. And when oyster cultivation fails at the top Northwest
hatcheries and farms, the effects on the industry are devastating.
A Shellfish Story
For centuries, shellfish farmers have cultivated oysters in Washington’s
Willapa Bay, a massive, shallow estuary separated from the Pacific Ocean by the
Long Beach Peninsula. The bay’s warm waters are particularly suited for growing
Pacific oysters, identified by their rough, fluted shells marked with purple
streaks, and a white interior bearing “a single muscle scar that is sometimes
dark, but never purple or black,” according to a Biological Report from the U.S.
Fish and Wildlife Service. The oyster was imported from Japan to the western
U.S. coast in 1903. “Puget Sound and Washington waters are a little bit cold
compared to what the oyster had in Japan,” says Dewey. “So it doesn’t reproduce
particularly well here. Except for a few areas—Willapa Bay is one of them.
There’s dependable natural reproduction from one year to the next. The water
basically has to get up to 72 degrees and stay there for three weeks for the
oysters to spawn.”
Beginning in 2005, these oysters in the bay, known as natural sets, stopped
reproducing. They have never successfully reproduced since. In 2006, the
hatchery-produced Pacific oysters followed suit. In the hatcheries, spawning
happens year-round in conditioning tanks where water temperature and algae
levels (for food) are closely controlled.
Both Taylor Shellfish and
Whiskey
Creek Shellfish Hatchery in Tillamook, Oregon, witnessed oyster larvae
die-offs that they couldn’t explain and that continued for years. Initially,
they suspected a bacteria known as Vibrio tubiashii was to blame. But even after
Whiskey Creek installed an expensive filtration system, the oyster larvae
continued to die. By 2008, Whiskey Creek, which alone accounts for 75% of all
oyster seedlings used by West Coast oyster farmers, had lost 80% of its oyster
larvae. Taylor Shellfish had lost 60%. Despite the controlled environment, the
ocean water they were pumping into their hatcheries was corrosive. Upwelling—or
deep ocean water rising to the surface following north winds off the Washington
coast—was carrying acidic water to the surface. The shellfish farmers were
experiencing the devastating impacts of ocean acidification sooner than
researchers had anticipated. With support from Senator Maria Cantwell (D-WA),
ocean acidification sensors were set up in 2010 near Washington’s hatcheries.
Combined with Integrated Ocean Observing System (IOOS) buoys from NOAA measuring
wind velocity, they track ocean acidity—and predict the upwelling events that
cause increased acidity—in real time.
Mark Wiegardt, co-owner of Whiskey Creek said: “Putting an IOOS buoy in the
water is like putting headlights on a car.” Adds Dewey: “All of a sudden we
could see all aspects of this water that was coming in our intake pipes. And it
was quite eye-opening. We were seeing pH levels down as low as 7.5. Normally
it’s 8.2.” To oyster larvae, it’s the difference between life and death.
When that acidic water entered the hatcheries, it caused oyster shells in
their critical formative period to dissolve. Oysters and other shellfish,
including clams and lobsters, and a host of sea creatures that include plankton
and corals, need calcium carbonate minerals to form their shells and skeletons.
Normally ocean water is full of these minerals, but as carbon dioxide (CO2)
emissions have climbed across the globe, the ocean has absorbed increasing
levels of CO2, causing ocean acidification to rise and the availability of these
minerals to fall.
“A lot of things we like to eat have these calcium carbonate shells and
they’re very sensitive to acidification,” says Richard Feely, Ph.D., a senior
scientist with NOAA and its
Pacific Marine
Environmental Laboratory (PMEL). “Just a small drop in pH can cause the
shells to begin to dissolve. It turns out that for many of these species, the
larval and juvenile stages are much more sensitive than the adults. And we’re
finding that they can die off quite rapidly even with the kinds of changes that
we’re seeing right now.”
Swallowing Emissions
Over the past 100 years, levels of carbon in the atmosphere have risen 30%—to
393 parts per million. And the oceans absorb a third of that carbon dioxide, or
approximately 22 million tons per day, in a process that Feely likens to adding
carbon to water to make soda. Once it sinks into the water, the carbon dioxide
reacts with water molecules to form carbonic acid; the carbonic acid then
releases hydrogen ions which in turn combine with carbonate ions (the ones that
shellfish and other creatures need) removing them from the water. Normally the
process of oceans soaking up our excess CO2 is a beneficial one—keeping global
warming in check. “Eventually, over a very long time, thousands of years, the
ocean will take up 85-90% of all the carbon that’s released,” says Feely. “We
thought that was a good thing.” But acidification is now happening at an
accelerated pace, and it’s already changing the ocean in profound ways.
A study published in Science in March 2012 found that ocean acidity may be
increasing faster today than it has during four major extinctions in the last
300 million years. The only time period that remotely resembles the ocean
changes happening today, based on geologic records, was 56 million years ago
when carbon mysteriously doubled in the atmosphere, global temperatures rose by
approximately six degrees and ocean pH dropped sharply, driving up ocean acidity
and causing a mass extinction among single-celled ocean organisms. It’s likely,
researchers surmise, that higher organisms also disappeared as a result. During
that extinction period, ocean pH levels fell by up to 4.5 units. In the last 100
years, ocean pH today has already fallen by .1 unit—10 times faster than during
that extinction period—and could drop another .3 units by the end of the century
if predictions from the Intergovernmental Panel on Climate Change are correct.
Such a drop in pH, says Feely, “would increase the acidity of the ocean by about
100% to 150%. That’s a dramatic change.”
The oyster die-offs are likely just the first sign of significant impacts to
come if carbon emissions aren’t reined in. Take, for example, the
pteropod or sea
butterfly. These tiny marine snails that appear winged and beautifully
translucent in close-ups are essential to the ocean food web. Ocean
acidification threatens the ability of pteropods to form their fragile shells,
putting a range of commercially important fish at risk that depend on the small
snails for food, including salmon, herring and yellowfin tuna as well as mammals
like baleen whales, ringed seals and marine birds. Scientist Gretchen Hofmann of
the University of California Santa Barbara said of pteropods to United Press
International: “These animals are not charismatic, but they are talking to us
just as much as penguins or polar bears. They are harbingers of change. It’s
possible by 2050 they may not be able to make a shell anymore. If we lose these
organisms, the impact on the food chain will be catastrophic.”
Coral Collapse
Corals, too, face direct threat from ocean acidification, which, as it robs
ocean water of carbonate ions, impedes their ability to form skeletons. Davey
Kline, Ph.D., a coral reef ecology expert at the University of Queensland in
Australia, first began diving in the Caribbean in 1997 and says at that time,
“there were still really beautiful, elaborate reefs with really high coral
coverage. Corals bigger than me that looked like giant trees forming a forest.
But in the 10 years I’ve been working in the Caribbean, I saw those once really
incredible reefs completely crash and disappear. And what were once these really
diverse, three-dimensional reef structures became seaweed beds. Where the corals
were gone, most of the fish were gone and all that was left was a lot of
stinging, nasty algae.”
It’s not just ocean acidification threatening these reefs, it’s a number of
factors including overfishing, disease, development and warming waters. But the
falling pH has a very specific impact on the corals’ ability to grow, making it
that much more difficult for them to withstand other stressors. Kline describes
the growth and erosion of coral reefs as “a really delicate balance.” Corals are
built by polyps—tiny anemone-like creatures that produce calcium carbonate
crystals, stacking them in intricate, interconnected branches faster than the
sea can erode their skeletons. “There have been a lot of studies showing that
under ocean acidification scenarios that corals and other organisms on the reef
calcify at a slower rate,” Kline says. “Even with just a little less growth, the
corals can be tipped into these situations where they’re getting eroded faster
than they can grow and the reefs start to dissolve.”
It is nearly impossible to quantify the importance of coral reefs to people
and the planet. In monetary figures, corals have been valued at $29.8 billion
per year in net global economic value because they support fisheries, tourism
and all the associated businesses, from hotels to restaurants. Reefs also
protect shorelines from damaging storm waters and prevent erosion; they are the
rainforests of the sea that provide a home for one million species; and they are
“the medicine cabinets of the 21st century” according to NOAA’s Coral Reef
Conservation Program, providing new sources of medicine to treat cancer, HIV,
heart disease, arthritis and other diseases. Reefs are thriving underwater
metropolises where fish spawn and hide from predators and bigger fish cruise
looking for food.
Sponges, the most primitive reef animals, house tiny fish in their cavernous
tubes and vases as they draw seawater into their pores. The critically
endangered hawksbill turtle, with its almond eyes, black spots and hooked beak,
rests on the reefs feeding on these sponges while the vulnerable dugong, a
flabby mammal with a wide snout and dolphin-esque tail, circles lagoons, feeding
on the reef’s seagrasses. Shrimp and crabs are ubiquitous in coral reef
environments around the world, hiding in crevices, providing cleaning services
and enjoying the ready food supply. And of course the fish, of every hue and
size and shape, with bodies designed to quickly maneuver through reef
structures, fend off predators with scalpel-like spines, scrape algae and avoid
stinging tentacles, all coexist in these incredible habitats.
“If we lose coral reefs we lose a substantial source of seafood for coastal
countries in the tropics in particular,” says Mark Spalding, president of the
Ocean Foundation. “You’re threatening the basic
productivity of the ocean.”
And the potential for a world without coral reefs is not far-fetched or far
off. The most recent report on reef health—
Status of Coral Reefs of the World:
2008—found that 19% of coral reefs were already lost, 15% were seriously
threatened within a decade or two, and 20% could be lost in 20 to 40 years. “If
we continue on the trajectory that we’re currently at,” says Kline, referring to
unchecked global emissions, “we will lose reefs as we know them. We’ll probably
see a transition from really diverse reefs to reefs with fewer species that are
tougher, weedier species that can deal with these dramatic conditions.
Associated with the loss of diversity of corals will be the loss of millions of
species that use corals as their homes. A lot of the fish and seafood that we
eat, the most critical part of their life stages are on coral reefs. So there
will be huge economic impacts in terms of loss of fisheries, loss of sustenance
for all the cultural communities and loss of tourism…These changes could all
happen within the next 30 or 40 years—by 2050, at the current rate of
change.”
Increased carbon dioxide in the atmosphere not only alters the ocean’s
chemistry, it’s increasing the temperature of the atmosphere and warming waters,
too. As ocean temperatures rise, a very important algae called zooxanthellae
(zoo-zan-thel-y) that provides food for corals—and contributes to their
remarkable colors—can no longer make food. That’s when corals bleach. “The
reason the corals become bright white is because most of their color is coming
from these algae,” says Kline. “And when they lose the algae because the water
is too warm and they can’t keep up this relationship anymore, you see the bare
skeleton.”
Sometimes bleaching happens en masse as when 95% of corals in the Philippines
bleached in 2010 after an El Niño event that raised ocean temperatures.
Increased ocean temperatures also make the waters more stratified—preventing
nutrient-rich water from below from rising to the surface and oxygen-rich water
from reaching the middle layers. This can lead to more widespread losses.
The Center for Ocean Solutions
writes: “Between 1951 and 1993 zooplankton biomass off Southern California
decreased by 80% as a result of warming surface waters.” Less oxygen reaching
the interior, meanwhile, a product of both this increased stratification and
significant nutrient runoff from farms, creates dead zones, a massive threat to
marine life. And unlike nutrient runoff, which can be brought under control
rather quickly, oxygen depletion that happens as a result of global warming
can’t be easily reversed.
“Ocean warming, acidification and deoxygenation are essentially irreversible
on centennial time scales,” found the Royal Society, a London-based group
specializing in scientific research, in a 2011 paper, “[O]nce these changes have
occurred, it will take centuries for the ocean to recover. With the emission of
CO2 being the primary driver behind all three stressors, the primary mitigation
strategy is to reduce these emissions.”
Piecemeal Solutions
It would be hard to find an ocean expert who does not agree that global
carbon dioxide emissions must be brought under control—and quickly—if we are to
prevent the wholesale deterioration of our oceans. Most also recognize that such
global agreements are the most difficult to come by, and that local protection
strategies and efforts to reduce stressors on corals and marine life are
important steps in at least staving off the impacts of ocean acidification and
global warming.
When it comes to reefs, designating reef environments as marine protected
areas (MPAs)—and enforcing that designation—is essential to protecting habitat.
But, notes the
World Resources Institute, of the
400 or more MPAs in more than 65 countries and territories, there are only a
handful that are truly large in scope—notably the Great Barrier Reef in
Australia, the Florida Keys National Marine Sanctuary and the Ras Mohammed Park
Complex in Egypt. Outside of these massive sites, they write “it is likely that
less than 3% of the world’s coral reefs are protected.” And in many cases, such
protections are on paper only. They cite the example of Johnston Atoll west of
Hawaii, which was designated a federal bird refuge in 1926, and became the
Pacific Marine National Monument under President George W. Bush in 2009.
“Probably among the earliest designations of a coral reef protected area, this
site has been subjected to massive military development, high atmospheric
nuclear testing, chemical waste disposal, and other threats,” the institute
notes.
At the Great Barrier Reef, the world’s largest coral reef ecosystem at
approximately 133,000 square miles (about the size of New Zealand), establishing
the Great Barrier Reef Marine Park in 1975 was a first step, but not until the
park was rezoned between 1999 and 2003 was the reef given the protection needed
to rebound from threats that include shipping, dredging, commercial fishing,
nutrient and pesticide runoff, coastal development and diving. Some 33% of the
Great Barrier Reef is designated as a Green Zone, or no-take zone, where any
activity beyond diving and underwater photography is prohibited or requires a
permit. There are seven zones in total, which allow varying degrees of fishing,
aquaculture, trawling and other activities, keeping them within managed limits.
The restrictions have led to major recoveries of reef fish—including the coral
trout and stripy sea perch—and declines in the crown-of-thorns starfish, a large
starfish with up to 21 arms that lives and preys on corals, killing them in the
process. The crown-of-thorns starfish proliferates in nutrient-rich water which
comes as a result of unchecked runoff.
“As much of the stress as you can remove from reefs you’re really going to
increase the chance that more of the reefs can make it,” says Kline. “Setting up
marine reserves and managing marine reserves well; minimizing pollution and
development near reefs; and using reefs in a sustainable way. Corals are living
animals and when people step on them or kick them with their fins it can cause
damage to the reefs. All these different factors can have an impact on the
overall future of coral reefs.”
Shellfish farmers with controlled hatchery environments can take some
precautions to prevent corrosive, acidic water from entering their breeding
tanks. Thanks to ocean buoys and sensors monitoring acidity and wind velocity,
farmers at Whiskey Creek now know that they have 24 hours following a north wind
before corrosive water wells up and enters their intake pipes. “When they see [a
north wind] happening,” says Dewey, “they fill all their tanks and they don’t
change their water as frequently as they should to avoid bringing corrosive
water in that would harm the larvae. They’ve adapted management protocols to get
around those corrosive events that are somewhat effective.”
But in order to track and manage ocean acidification more monitoring is
needed, and the federal 2013 budget cuts $2.5 million in funding for obtaining
and delivering data from the buoys in Washington state. That led Sen.
Cantwell—who sits on the Energy and Natural Resources Committee—to confront NOAA
Administrator Jane Lubchenco at a March 7, 2012 hearing, saying: “Cutting back
on science that is important for jobs and the economy can’t be substituted.”
Lubchenco admitted during the hearing that cutting the funding for ocean
acidification monitoring “is one of those choices that I’m not happy about
because it’s a program that is very, very important. We will continue to do
monitoring; it’s not that we’re not doing anything. We won’t be able to do it at
the scale we would like to do it.”
Other fixes shellfish hatcheries can employ include filling the tanks later
in the day, when the water has warmed and the pH has increased, and running the
water over clam or oyster shells before filling tanks, which also increases pH.
It’s an imperfect process, but workable, for now.
What is critical to reducing the effects of ocean acidification surrounding
coasts, says Spalding, is to protect and
restore seagrass. Florida’s coasts,
for example, have lost significant seagrass, in large part from dredge and fill
operations. This seagrass is not only essential to provide habitat for fish, but
the plants store CO2 in their roots, lowering the ocean’s pH. Mangroves, which
are “forested wetlands,” serve the same function, and are similarly threatened,
particularly by shrimp aquaculture. Since the 1980s, 20% of the world’s
mangroves have been destroyed, according to the Food and Agriculture
Organization of the U.N.
“One solution [to ocean acidification] is to make sure that we do everything
we can to preserve and protect
salt
marshes, sea grasses and mangroves in particular,” Spalding says, “and be
aggressive about restoring those that we’ve lost to recreate the carbon sink
potential of the ocean.” If this restoration happened on a global level, it
could help lower the pH overall; and there’s speculation, Spalding adds, that
such strategies might work to control the pH of individual areas.
As the Royal Society noted, however, the only real, overarching solution to
ocean acidification is setting significant global targets for reducing CO2
emissions and sticking to them. In lieu of that, it means local
communities—particularly coastal “hotspots”—must adopt ways to address ocean
acidification using existing laws, according to a May 2011 report by Feely and
other experts. That includes enforcing the federal Clean Water Act which
requires the control of pollutants and runoff (both of which increase
acidification), enacting zoning policies that address runoff and emissions and
enforcing federal laws on emission limits.
These local strategies, Feely says, may offer the only immediate possibility
for mitigating ocean acidification. In terms of setting reduced targets for
worldwide carbon dioxide emissions, he says, we’ll almost certainly pass the
“safe” point from the oceans’ perspective. “One of the problems we’re faced with
is trying to figure out what’s a safe level for CO2,” Feely says. “And many
folks have suggested that we would like to keep global warming below a level of
total increased temperature of 2°C. To do that, you have to have CO2 levels in
the atmosphere below 450-500 parts per million. A CO2 concentration of 450-500
ppm means the Arctic Ocean and good portions of the Antarctic Ocean would become
corrosive to all calcifying organisms from surface to bottom. In fact, from the
retrospect of ocean acidification, we’ll reach thresholds long before we get to
those levels.”
~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Brita Belli is editor of E and author of
The Autism Puzzle: Connecting the Dots Between Environmental Toxins and Rising
Autism Rates (Seven Stories Press).
