Tag Archives: ocean acidification

Desperately Seeking a Rapid-Onset Response to a Slow-Onset Event – The Case of Ocean Acidification

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International Institute for Sustainable Development. May 19th, 2014. By David Osborn, Director, Environment Laboratory, IAEA

I last wrote an article for this bulletin in July 2009 (Guest article #17). On that occasion, I reflected on the immense expectations surrounding the climate negotiations in Copenhagen and the need to ‘Seal the Deal.’ I can see many of you holding back a wry smile as you remember that ambitious campaign so soon forgotten.

Back in those heady days of hope and anticipation, amid all the noise and distraction, I highlighted the pressing need to not forget the changing ocean. I invited governments to acknowledge the impact of climate change on the ocean and find ways to proactively ensure its resilience. Longing for a rapid onset of reform, I called for an ‘ocean of change’ that would finally recognise the centrality and criticality of ocean health to both mitigating and adapting to the effects of climate change.

Alas, my hopes for a tsunami of reform – while not altogether in vain – were far from realised. Now in 2014, as ambition and hope again escalate in the recycled world of climate change negotiations, like an undefeatable phoenix the plight of the world’s coasts and oceans must once again be thrust to the fore to ensure their centrality in the solution is not overlooked.

Key among the myriad of challenges facing the marine environment is the slow-onset phenomenon known as ocean acidification. As atmospheric carbon dioxide concentration climbs, ocean pH falls. It’s that simple. Falling pH in turn makes it harder for marine life to capture carbonates and fix calcium to build shells and skeletons. It may be a death sentence for many species, particularly those where calcification is a part of their early life cycle. The impacts of ocean acidification will be felt at the microscopic scale, e.g. calcifying plankton, through to the habitat scale, e.g. coral reefs. The implications for the marine food webs and the provision of ecosystem services are potentially catastrophic with extinctions in the next 50-200 years being a very realistic scenario.

Clearly, more and accelerated science is urgently needed. In this regard, I am pleased to report that the Environment Laboratories of the International Atomic Energy Agency (IAEA) in Monaco are making this issue a focus of their work, using for example, radio-isotopes of calcium to better understand the past, present and future impacts of ocean acidification. This includes observing physiological and ecological effects under different climate change scenarios. In an effort to improve collaboration and shared learning, the laboratories operate the Ocean Acidification International Coordination Centre (OA-ICC). This is currently funded by the Peaceful Uses Initiative of the IAEA; however the urgent need for expanded research, data generation and knowledge products far outweighs the resources that are currently available.

The challenge of addressing ocean acidification is a cross-cutting one, relevant to the three dimensions of the ongoing climate change negotiations: mitigation, adaptation, and loss and damage.

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Workshop Offers Look at Grays Harbor of the Future

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The Daily World, April 10th, 2014. By Brionna Friedrich

A workshop Tuesday on ocean acidification and rising sea levels offered a peek into Grays Harbor’s potential future, and aimed to start a conversation about turning the challenges of climate change into opportunities.

Brad Warren, director of Global Ocean Health, said he hopes to change the way people think about climate change.

“The language is loss, ‘We’re going to lose this much land,’ ” Warren said. “Well, if you look at this from the ocean point of view, which is where a fair number of people around here make a living, there’s going to be a fair number of opportunities there.”

That change may prove to be a challenge of its own. About 30 people attended the workshop, mostly agency officials joined by a few interested residents and local policymakers. Nearly all had ideas, concerns and questions about climate change, but few were ready to focus on the suggestion of creating new industries, like harvesting underwater plants.

“It’s a beginning. And that’s probably enough,” Warren said. “It will be really interesting to come back and track this conversation as it matures over time. I think it’s really clear that people are ready to think hard about sea level rise, and that’s pretty complicated by itself. And there’s a lot of resistance to thinking about how it interacts with another complicated process” like ocean acidification.

Todd Sandell of the Wild Fish Conservancy offered one tool in increasing that understanding locally. He and Andrew McAninch were initially only researching data on juvenile salmon habitat in the Grays Harbor area.

“It became rapidly apparent 
 that the elephant in the room that people weren’t really talking about is sea level rise,” Sandell said. “That’s going to undermine a lot of the work that’s been done over past decades, putting in tide gates and things like that.”

In 2012, the conservancy used lidar data from the Federal Emergency Management Agency to build a better model of what climate change could look like on the Harbor.

Sandell and McAninch modeled out to 2100. Compared to Grays Harbor in 1981, when modeling started, the 2100 Grays Harbor will lose 83 percent of its mud flats, have 2.4 times the salt marsh and six times as much irregularly flooded marsh area. Traditional marsh will be 26 times larger.

Forested swamp land showed a 97 percent reduction as a result of sea level rise, Sandell said. Goose and Sand islands would be completely underwater.

Sandell said as salt water penetrates deeper and deeper into the Harbor and into the sloughs, trees may die because they can’t tolerate the salinity. That may lead to further collapse during flooding.

In Willapa Harbor, Sandell said the numerous dikes might lead to good habitats for various sea creatures that like shallow water for about 25 years. After that, he said, the dikes will create more problems than they solve.

“That’s one of the reasons you can’t just build a bunch of dikes and say, ‘We won’t move an inch,’ ” Sandell said. “I wouldn’t want to fight the ocean that much.”

One of the challenges in getting a clear picture of what the Twin Harbors might look like with rising oceans is limited by data. Scientists don’t have a clear picture of what the underwater landscape looks like.

Sandell said the model they used has a vertical error of one to three meters, meaning the elevations they used for their modeling could have some significant variation from where the ground actually is. That translates to some potentially significant differences in the horizontal borders they project. Still, it’s a significant improvement in accuracy over previous models.

Getting clearer and clearer pictures of what’s happening to the habitat around us is the only way we’ll ever start to cope with the many and varied impacts of climate change, Warren said.

“I thought a really important thing somebody brought up today is that the perception of urgency is not really there, around either sea level rise or ocean acidification,” Warren said. “In order to get county governments to address this issue, when they can’t see their own interests at risk now, it’s a really important challenge. I would argue that the challenge there is not that there is no change affecting their interests, nor that that change is not urgent. It’s that we don’t have the observing systems in place to be able to see what’s happening to us.”

Coastline changes may actually present more opportunity for burying carbon.

About 0.5 percent of ocean area roughly matches the carbon absorption of all the world’s forests. Salt marsh buries 10 times as much carbon per acre every year than a Brazilian rainforest, Warren said.

In Asia, harvesting underwater plants that thrive in acidic water is already a $7 billion per year industry, cleaning the water at the same time.

With better information, policy makers will be able to take advantage of opportunities like that, using better planning for coastlines and flood plains.

“People are really intelligent when they can see what’s happening to them. We’re not very intelligent when we can’t see,” he added.

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Workshop Takes a Practical, Proactive Look at Ocean Acidification

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The Daily World, April 5th, 2014. By Brionna Friedrich

The frightening impacts of a changing climate are sometimes unavoidable, but an upcoming workshop takes a proactive look at how to cope with changing coastlines and ocean chemistry.

“If we can snatch opportunity out of the jaws of climate change, we’ll be doing a smart thing,” said Eric Swenson, communications and outreach director of Global Ocean Health. “That’s a real message I hope resonates and people can act on. Can we benefit from the coming circumstances?”

The non-profit initiative focuses on the impacts of ocean acidification, the absorption of carbon dioxide into ocean waters, which is already impacting local industries like shellfish growers.

It specifically works with seafood producers and coastal communities on options for adaptation.

The free workshop, set for Tuesday in the Rotary Log Pavilion in Aberdeen, will connect climate change and ocean acidification experts with local and regional policymakers and the general public.

The morning session, from 9 a.m. to noon, will feature speakers on changing aquaculture and how marine plants and grasses can help absorb CO2.

Stephen Crooks, climate change program director for Environmental Services Associates, has recently briefed the White House and the United Nations on the impacts of estuary restoration, Swenson said. “Now he’ll be doing a briefing for the Washington coast in Aberdeen,” he said. “We’ve got some actual world-class folks on the agenda.”

Marine and coastal vegetation provides opportunities, from contributions to overall estuary health to a possible commercial enterprise, harvesting food and biofuel.

“This isn’t pie-in-the-sky, people are doing this and making money at it in Asia,” Swenson said.

It could also provide a tool for shellfish farmers. Acidic ocean waters can decimate delicate oyster larvae.

“If you can just move the meter a point or two in some key areas, it’s the difference between life and death,” Swenson said.

“There’s a fair amount of research that shows that when shellfish and seagrasses co-exist — the right kind of seagrasses — it’s to the benefit of both,” he continued.

“We will be looking at how plants sequester the carbon. The salt marsh plants, for instance, do a job that’s about five times as effective as a tropical forest, so photosynthesis can really be made to work for us.”

A free lunch will be offered before the afternoon session, from 1 p.m. to 4 p.m., which will discuss local planning and policy processes that can help in preparation for a changing coastline.

“We’re bringing (ocean acidificaton) into a wider context of what the coast is going to look at in 20, 30 or 40 or more years, and it’s going to be very different than what it is now,” Swenson said. “By trying to consider what the coastline is going to look like with the higher sea, we may be able to shelter shellfish, we may be able to protect our estuaries, which are such nurseries for a variety of sea life.”

“If we learn to plan for it well, sea level rise might be more than just a problem — which it certainly will be — but an opportunity,” Global Ocean Health Director Brad Warren wrote in a press release. “Higher water will make more room for estuarine ecosystems that can sometimes chemically shelter vulnerable larvae from corrosive waters. It won’t be a smooth transition, but sea level rise may open up new areas for farming shellfish and marketable marine macroalgae. It will increase coastal habitats that support hunting and fishing and expand the nursery grounds that support most of the world’s seafood supply.”

Some basic understanding of ocean acidification will help for those who attend the workshop, Swenson said, but scientific expertise isn’t a requirement.

“I think people who have at least a fundamental grasp of what we’re talking about will be better served by the meeting, but it is designed to be open to the public, free of charge, with that free lunch included, in an attempt to draw in people who want to learn more about this,” Swenson said.

The Rotary Log Pavilion is located at 1401 Sargent Blvd. in Aberdeen. No registration is required for the workshop.

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National Climate Assessment Released

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May 6th, 2014, National Climate Report Overview

Climate change, once considered an issue for a distant future, has moved firmly into the present. Corn producers in Iowa, oyster growers in Washington State, and maple syrup producers in Vermont are all observing climate-related changes that are outside of recent experience. So, too, are coastal planners in Florida, water managers in the arid Southwest, city dwellers from Phoenix to New York, and Native Peoples on tribal lands from Louisiana to Alaska. This National Climate Assessment concludes that the evidence of human-induced climate change continues to strengthen and that impacts are increasing across the country.

Americans are noticing changes all around them. Summers are longer and hotter, and extended periods of unusual heat last longer than any living American has ever experienced. Winters are generally shorter and warmer. Rain comes in heavier downpours. People are seeing changes in the length and severity of seasonal allergies, the plant varieties that thrive in their gardens, and the kinds of birds they see in any particular month in their neighborhoods.

Other changes are even more dramatic. Residents of some coastal cities see their streets flood more regularly during storms and high tides. Inland cities near large rivers also experience more flooding, especially in the Midwest and Northeast. Insurance rates are rising in some vulnerable locations, and insurance is no longer available in others. Hotter and drier weather and earlier snow melt mean that wildfires in the West start earlier in the spring, last later into the fall, and burn more acreage. In Arctic Alaska, the summer sea ice that once protected the coasts has receded, and autumn storms now cause more erosion, threatening many communities with relocation.

Scientists who study climate change confirm that these observations are consistent with significant changes in Earth’s climatic trends. Long-term, independent records from weather stations, satellites, ocean buoys, tide gauges, and many other data sources all confirm that our nation, like the rest of the world, is warming. Precipitation patterns are changing, sea level is rising, the oceans are becoming more acidic, and the frequency and intensity of some extreme weather events are increasing. Many lines of independent evidence demonstrate that the rapid warming of the past half-century is due primarily to human activities.

The observed warming and other climatic changes are triggering wide-ranging impacts in every region of our country and throughout our economy. Some of these changes can be beneficial over the short run, such as a longer growing season in some regions and a longer shipping season on the Great Lakes. But many more are detrimental, largely because our society and its infrastructure were designed for the climate that we have had, not the rapidly changing climate we now have and can expect in the future. In addition, climate change does not occur in isolation. Rather, it is superimposed on other stresses, which combine to create new challenges.

This National Climate Assessment collects, integrates, and assesses observations and research from around the country, helping us to see what is actually happening and understand what it means for our lives, our livelihoods, and our future. The report includes analyses of impacts on seven sectors – human health, water, energy, transportation, agriculture, forests, and ecosystems – and the interactions among sectors at the national level. The report also assesses key impacts on all U.S. regions: Northeast, Southeast and Caribbean, Midwest, Great Plains, Southwest, Northwest, Alaska, Hawai’i and Pacific Islands, as well as the country’s coastal areas, oceans, and marine resources.

Over recent decades, climate science has advanced significantly. Increased scrutiny has led to increased certainty that we are now seeing impacts associated with human-induced climate change. With each passing year, the accumulating evidence further expands our understanding and extends the record of observed trends in temperature, precipitation, sea level, ice mass, and many other variables recorded by a variety of measuring systems and analyzed by independent research groups from around the world. It is notable that as these data records have grown longer and climate models have become more comprehensive, earlier predictions have largely been confirmed. The only real surprises have been that some changes, such as sea level rise and Arctic sea ice decline, have outpaced earlier projections.

What is new over the last decade is that we know with increasing certainty that climate change is happening now. While scientists continue to refine projections of the future, observations unequivocally show that climate is changing and that the warming of the past 50 years is primarily due to human-induced emissions of heat-trapping gases. These emissions come mainly from burning coal, oil, and gas, with additional contributions from forest clearing and some agricultural practices.

Global climate is projected to continue to change over this century and beyond, but there is still time to act to limit the amount of change and the extent of damaging impacts.

This report documents the changes already observed and those projected for the future.

It is important that these findings and response options be shared broadly to inform citizens and communities across our nation. Climate change presents a major challenge for society. This report advances our understanding of that challenge and the need for the American people to prepare for and respond to its far-reaching implications.

Read the full report here

New Ocean Acidification Study to Launch in Prince William Sound

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AOOS.org, By Darcy Dugan, April 29th, 2014

Beginning this week, two surface wave gliders, resembling yellow surfboards, will be cruising around Prince William Sound as part of a five-month monitoring program to measure ocean acidification. Simultaneously, state-of-the-art instrumentation installed on a glacier tour boat will monitor glacial runoff while an underwater autonomous glider will patrol beneath the surface looking for plumes of water that could be harmful to some species.

A remote-controlled glider, similar to the one shown here, will measure ocean acidification in Prince William Sound from May to September. Photo credit: Richard Feely, NOAA/PMEL

A remote-controlled glider, similar to the one shown here, will measure ocean acidification in Prince William Sound from May to September. Photo credit: Richard Feely, NOAA/PMEL

The project, funded mostly by the National Oceanic and Atmospheric Administration’s Ocean Acidification Program, is led by Dr. Jeremy Mathis of the Pacific Marine Environmental Laboratory and Dr. Wiley Evans from the University of Alaska Fairbanks (UAF) Ocean Acidification Research Center in partnership with the Alaska Ocean Observing System (AOOS).

Scientists estimate that the ocean is 25% more acidic today than it was 300 years ago, largely due to increasing levels of atmospheric carbon dioxide (CO2) from burning fossil fuels and changes in land use. Almost half of the CO2 emitted remains in the atmosphere, with the land and ocean absorbing the rest. When the ocean absorbs CO2, its pH balance changes through a process called ocean acidification. Because cold water can absorb more CO2 than warm water, acidification can disproportionately impact coastal regions around Alaska.

Recent publications by Dr. Mathis and Dr. Evans have shown that the process of ocean acidification may be worsened around tidewater glaciers due to the freshwater melt plumes that occur is summer and fall. “The glacier melt plumes have some really unique chemistry that can exacerbate ocean acidification and impact the environment in Prince William Sound and out into the Gulf of Alaska,” Mathis said. “Our goal is to use the latest technology to find out what’s happening so we can communicate that to Alaska residents and stakeholders.”

According to AOOS Executive Director Molly McCammon, the research effort builds upon the partnership developed with the OA Research Center at UAF to support statewide OA monitoring. The consortium supports five buoys around the State, as well as twice a year sampling in the Gulf of Alaska, and development of a Gulf of Alaska OA forecast model. Data from the monitoring efforts will be available on both the AOOS website and the UAF’s OA Research Center website. “With this new effort, we’re increasing our ability to view and understand Alaska’s oceans in four dimensions – two dimension space, depth and time.”

When completed in early September, the study will have provided the longest continuous observations of ocean acidification in Alaska to date. “We are very proud to have the opportunity to partner with AOOS and be the leaders in glider technology in Alaska,” said Mathis. “This work could be a game-changer in our understanding of how ocean acidification will impact our state.”

East Coast’s First Ocean Acidification Bill Becomes Law

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Maine Legislature Press Release April 30th, 2014

AUGUSTA – The East Coast’s first measure to address the threat of ocean acidification became law Wednesday.

“Maine is taking the lead on ocean acidification on the Eastern seaboard. We understand just how dangerous it is to our marine environment, jobs and way of life,” said Rep. Mick Devin, D-Newcastle, the bill’s sponsor and a marine biologist. “We will address this threat head-on and find ways to protect our marine resources and economies.”

LD 1602 became law without the signature of Gov. Paul LePage. It went into effect immediately.

The measure would establish a commission to study and address the negative effects of ocean acidification on the ecosystem and major inshore shellfisheries. The committee membership would be made up of stakeholders including fishermen, aquaculturists, scientists and legislators.

“We who work on the ocean observe the day to day effects of small changes in climate and the destruction caused by such things as ocean acidification,” said Richard Nelson, a fisherman from Friendship. “We are solely dependent on a resource that must be managed intelligently and effectively in order for it to remain healthy and available to us.”

Rising levels of carbon dioxide from fossil fuel use are causing changes in ocean chemistry. As carbon dioxide and seawater combine, carbonic acid forms. Carbonic acid can dissolve the shells of shellfish, an important commercial marine resource. Over the past two centuries, ocean acidity levels have increased 30 percent.

If left unchecked, ocean acidification could cause major losses to shellfisheries like clams, oysters, lobsters, shrimp and sea urchins and put at risk thousands of jobs and billions of dollars to the state’s economy.

“We’re glad to see Maine leading on this issue,” said Rob Snyder, president of the Island Institute, which helped draft the legislation. “The industries that will be affected by ocean acidification employ thousands of Mainers – especially in island and coastal communities – and they contribute $1 billion to our state’s economy. It’s critical to learn more about the solutions to ocean acidification that will protect those jobs.”

Shellfish hatcheries on the West Coast have failed in recent years due to 60 to 80 percent production losses caused by ocean chemistry changes, which can take place quickly. A 2007 study by the National Oceanic and Atmospheric Administration discovered changes in ocean chemistry not expected for another 50 to 100 years on the West Coast.

Devin’s bill is one of the key legislative issues of the Environmental Priorities Coalition this year. The coalition cited research that found the Gulf of Maine is more susceptible to the effects of ocean acidification than other parts of the East Coast.

Lawmakers Pass East Coast’s First Ocean Acidification Bill

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Maine Insights, By Ramona Du Houx, April 18th, 2014

The Legislature on Thursday passed the East Coast’s first bill to address the threat of ocean acidification as the Senate gave the measure its final approval with a vote of 33-0. The bill, LD 1602, now goes to Gov. Paul LePage.

“Maine has the opportunity to lead on this issue,” said Rep. Mick Devin, the bill’s sponsor and a marine biologist. “The overwhelming support for my bill shows that Maine understands that ocean acidification is a real problem. It poses a threat to our coastal environment and the jobs that depend on it. We must address this threat head-on.”

The measure would establish a commission to study and address the negative effects of ocean acidification on the ecosystem and major inshore shellfisheries. The committee membership would be made up of stakeholders including fishermen, aquaculturists, scientists and legislators.

Rising levels of carbon dioxide from fossil fuel use are causing changes in ocean chemistry. As carbon dioxide and seawater combine, carbonic acid forms. Carbonic acid can dissolve the shells of shellfish, an important commercial marine resource. Over the past two centuries, ocean acidity levels have increased 30 percent.

If left unchecked, ocean acidification could cause major losses to shellfisheries like clams, oysters, lobsters, shrimp and sea urchins and put at risk thousands of jobs and billions of dollars to the state’s economy.

Shellfish hatcheries on the West Coast have failed in recent years due to 60 to 80 percent production losses caused by ocean chemistry changes, which can take place quickly. A 2007 study by the National Oceanic and Atmospheric Administration discovered changes in ocean chemistry not expected for another 50 to 100 years on the West Coast.

Devin’s bill is one of the key legislative issues of the Environmental Priorities Coalition this year. The coalition cited research that found the Gulf of Maine is more susceptible to the effects of ocean acidification than other parts of the East Coast.

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How Ocean Acidification Impacts Lobster Larvae

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Maine School of Marine Sciences, by Ian Jones, April 15th 2014

Third-year marine sciences major  Ian Jones of Canton, Conn., is studying how ocean acidification impacts lobster larvae, an important resource for the Maine economy.

Jones works with American lobsters raised at UMaine’s Aquaculture Research Center (ARC). The lobster larvae were raised last summer at various pH levels, replicating natural environments and the impact of ocean acidification. Jones weighed and photographed approximately 700 lobster larvae to monitor their growth in these different environments. The hypothesis: slower growth and more irregular development occur at lower pH. This creates adaptation problems for lobsters dealing with increased environmental CO2 levels.

“We will certainly see greater ocean acidification in the future as an effect of climate change. As atmospheric levels of CO2 continue to increase from human input, so do the CO­2 levels of the upper ocean,” says Jones.

Along with lobster larvae, Jones also monitored seahorses in Tim Bowden’s lab. The seahorses, which were dealing with a mycobacterial infection, were in the care of Jones while an antibiotic treatment was created. He also raised juvenile seahorses last year. Through this experience, Jones learned about seahorse aquaculture, proper feeding protocols, tank chemistry and more.

“Not much is known about seahorse aquaculture relative to raising other fish, so although information on raising newborns was limited, it was a fun challenge figuring out our own system that worked.”

This fall, Jones will travel to the Darling Marine Center on the Damariscotta River, where he and other UMaine students will further the hands-on work they do in the classroom through the Semester By the Sea program.

Jones plans to attend graduate school to study sensory biology and/or the effect of climate change on marine animals.

Why is your lobster research important? Research on American lobster growth at lowered pH is incredibly important first, because there has been little climate change study on this particular species and second, any slowing or other adverse effects on lobster growth could have serious impacts on the health of the lobster fishery, which Maine, of course, greatly depends on. Delayed lobster larvae development means it will take longer for lobsters to get to market size, and predation risk may increase as well, causing fewer individuals to grow into adults and lowering the overall abundance of adult lobsters. Changes in lobster abundance can in turn upset ecosystem balance by changing the abundance of organisms that depend on lobster as prey and organisms lobsters prey on. These trophic cascades have the power to reduce the presence of many species in addition to just the lobster, consequently reducing biodiversity.

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Sea Life on the Bottom of Sound is in Trouble

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Kitsap Sun, By Christopher Dunagan
Sunday, April 6, 2014
Researchers are working to explain a mysterious 10-year decline in the populations of a wide variety of organisms that live at the bottom of Puget Sound.
Studies in 1999 and 2009 showed a drop in the population of benthic invertebrates in central Puget Sound, according to a report released last summer by the Washington Department of Ecology. The analysis also showed a decline in the number of species that researchers found, a condition also seen in other areas of Puget Sound.
Toxic chemicals in the sediments don’t appear to be the driving factor for the decline, experts say. The actual cause has not been identified, but a number of ideas have been proposed.
“We’ve been talking to a lot of people and trying to figure out what could be influencing the benthos,” said Maggie Dutch, lead scientist for Ecology’s Puget Sound Sediment Monitoring Program.
As found in the study, chemicals measured were generally unchanged over the 10-year period, and measurable decreases were seen in the concentrations of lead, mercury, tin and polycyclic aromatic hydrocarbons from central Puget Sound. Laboratory tests showed only slightly greater problems over the decade when amphipods and sea urchin eggs were exposed to the sediments, so people were left wondering why the numbers declined and why some species went missing.
THE BENTHIC COMMUNITY
Benthic organisms — including a variety of tiny worms, clams and crustaceans — live in the mud and feed largely on dead matter that sinks to the bottom of Puget Sound. These tiny invertebrates, in turn, are eaten by other bottom-dwellers, such as crabs, shrimp, and by fish. They are one of the primary links into a food web that supports salmon, marine mammals and humans.
Gray whales eat the benthic creatures directly by swimming down, scooping up sediments and sifting the prey through the baleen around their mouths.
“Benthic invertebrates are overlooked by most people,” Dutch said. “They are in direct contact with the sediments. They live on them, feed on them. If there are contaminants, they will pick them up and pass them up through the food chain.”
When Ecology launched its long-range monitoring program in 1989, biologists generally assumed that the greatest problem for benthic organisms was the toxic contamination left behind by historical industries. In fact, chemicals are known to have serious effects on the benthos, as observed in several urban waterways. But declines in abundance also have been observed in some rural bays where relatively little chemical contamination exists. Such areas include Hood Canal, the Strait of Georgia, the Eastern Strait of Juan de Fuca and the San Juan Islands.
Over the past 25 years, some of the most toxic underwater sites have been cleaned in Puget Sound. Such projects often involve dredging to remove the worst of the contamination, followed by the addition of clean sediments to “cap” the pollution and keep it from escaping back into the environment.
Positive effects from the cleanups have been noted in some places, as shown in focused studies on the urban bays, Dutch said. For example, the general quality of sediments in Seattle’s Elliott Bay showed a positive shift from 1998 to 2007, with decreases in polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs).
In Kitsap County’s urban bays — namely Sinclair and Dyes inlets, Liberty Bay and Port Orchard Passage — concentrations of arsenic, lead and some PAHs decreased from 1998 to 2009, while concentrations of several metals and other PAHs increased.
But during that time, the total area of the bottom where benthos were judged as “adversely affected” increased from 9 percent in 1998 to 29 percent in 2009. In 1998, most of the “adversely affected” areas were found in Sinclair Inlet, but by 2009 all of Liberty Bay was similarly affected.
FACTORS AT WORK
In most areas, toxic chemicals alone fail to explain the general decline in the benthos, Dutch said. The complexity of the Puget Sound ecosystem might preclude a simple answer to the mystery, but these are some factors under consideration:
Chemicals not tested: Unknown substances might be creating problems. For example, in Budd Inlet near Olympia, some areas had no benthic organisms at all, yet tests for 262 toxic chemicals revealed relatively low contamination. Now, experts believe that untested chemicals — possibly hazardous dioxins — could be to blame.
“Emerging chemicals”: Studies are just beginning to identify problems caused by pharmaceuticals and personal-care products, which can mimic hormones and disrupt growth, behavior and reproduction in exposed animals. Some of these chemicals have been found in Puget Sound sediments.
Planktonic shift: Christopher Krembs of Ecology’s Water Quality Monitoring Program has hypothesized that excess inputs of nitrogen from human sources might be reducing the abundance of one type of plankton (diatoms) in favor of another type (dinoflagellates). When they die, diatoms more readily sink to the bottom and feed the benthos.
Changes in sediments: Grain size and organic material are determining factors for what grows in the sediments. In some areas, changes in land use have affected the quality of the sediments, especially at river mouths. Large sediment loads can kill off sensitive species, leaving only those able to cope with dramatic change.
Low-oxygen conditions: Nitrogen also has been implicated in creating low-oxygen conditions, known as hypoxia. Excess nitrogen encourages the growth of plankton, which then die and decay. During decomposition, bacteria can use up the available oxygen, leaving deadly conditions for other organisms.
Increased acidification: Lower pH levels, associated with both hypoxia and climate change, can affect many species, especially those with calcium shells. An oyster hatchery on Hood Canal, operated by Taylor Shellfish Farms, was forced to alter its water intake in Quilcene Bay because of low-oxygen conditions. Experts found that the tiny oyster larvae were dying when they were unable to produce a healthy shell.
Natural oceanic cycles: Scientist have long studied cycles in ocean conditions, including the long-term Pacific Decadal Oscillation and the shorter-term El Niño/La Niña cycles. These cycles can shift temperature, acidity, nutrients and oxygen levels, but their effects on the benthos are not fully understood.
NEED FOR COLLABORATION
As the studies move forward, it has become clear that Ecology’s Sediment Monitoring Program must work more closely with the Water Quality Monitoring Program and other research efforts, said Dutch, who has worked for Ecology since 1989.
“Putting pieces of the puzzle together means communicating with others doing research in this area,” she said. “Various programs have grown and evolved to answer their own questions. But you get to the point where you start to see how all these parameters are connected.”
One can learn from other areas as well, she said, but Puget Sound has some of the greatest benthic diversity in the world. East Coast estuaries, such as Chesapeake Bay, has just one-fourth the number of species found in Puget Sound.
To help communicate the findings about sediment chemistry and benthic organisms, Dutch and her colleagues developed three numerical “indexes” to describe the health of sediments within a bay or across a region of Puget Sound.
One is the “sediment chemistry index,” which considers the levels of toxic chemicals in the waterway. Urban bays in Kitsap County had better scores than Seattle’s Elliott Bay or Tacoma’s Commencement Bay, but Elliott Bay has shown the greatest improvement from 1998 to 2007.
The second is the “sediment toxicity index,” which involves exposing amphipods and sea urchin eggs to the sediments taken from the waterway. Elliott Bay, Commencement Bay and Kitsap bays were all close in the first round of testing. But 10 years later only Elliott Bay had improved, and Kitsap bays had shown a 7 percent decline.
The third is the “sediment benthic index,” which looks at the numbers and species of bottom organisms found in the area. A numerical score is under development. For now, areas are described as either “adversely affected” or “unaffected.”
Finally, the three indexes are put together to create a “sediment quality triad index,” which is being used by the Puget Sound Partnership as a “vital signs indicator” to describe progress in cleaning up Puget Sound. Largely because of the mysterious declines in benthic populations and species, the overall triad index has declined in five of the six Puget Sound regions. That worsening trend must be reversed to meet the partnership’s 2020 target to improve sediments to an unimpaired status.

Ocean Acidification Impairs Vermetid Reef Recruitment

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Feb 28th, 2014, Nature.com

Vermetids form reefs in sub-tropical and warm-temperate waters that protect coasts from erosion, regulate sediment transport and accumulation, serve as carbon sinks and provide habitat for other species. The gastropods that form these reefs brood encapsulated larvae; they are threatened by rapid environmental changes since their ability to disperse is very limited. We used transplant experiments along a natural CO2 gradient to assess ocean acidification effects on the reef-building gastropod Dendropoma petraeum. We found that although D. petraeum were able to reproduce and brood at elevated levels of CO2, recruitment success was adversely affected. Long-term exposure to acidified conditions predicted for the year 2100 and beyond caused shell dissolution and a significant increase in shell Mg content. Unless CO2 emissions are reduced and conservation measures taken, our results suggest these reefs are in danger of extinction within this century, with significant ecological and socioeconomic ramifications for coastal systems.

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Mediterranean vermetid reefs.

(A) A pristine vermetid reef at low tide in NW Sicily, Italy. (B) Collection of a vermetid core in the outer rim of a vermetid reef; black spots are the shell openings of Dendropoma petraeum cemented by the coralline alga Neogoniolithon brassica-florida. (C) A vermetid core transplanted in the intertidal off Vulcano Island. (D) A recruit newly settled on the coralline alga (top left) and the shell opening with the operculum of a D. petraeum adult (below). Photo credits: R.C. (A); M.M. (B,C); M.M. and M.F. (D)