Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

World Oceans Month Brings Mixed News for Oysters

13.06.2013
Ocean acidification inhibits shell formation, but interventions at hatcheries may offset some effects, scientists find

In World Oceans Month, there's mixed news for the Pacific Northwest oyster industry.


Research site in Netarts Bay, Oregon, at low tide; rows of bags contain seed oysters.

For the past several years, it has struggled with significant losses due to ocean acidification. Oyster larvae have had mortality rates high enough to render production no longer economically feasible.

Now a new study documents why oysters appear so sensitive to increasing acidity, but also offers some hope for the future.

It isn't necessarily a case of acidic water dissolving the oysters' shells, scientists say. It's water high in carbon dioxide altering shell formation rates, energy usage and, ultimately, the growth and survival of young oysters.

"The failure of oyster seed production in Northwest Pacific coastal waters is one of the most graphic examples of ocean acidification effects on important commercial shellfish," said Dave Garrison, program director in the National Science Foundation's (NSF) Division of Ocean Sciences.

NSF funded the study through its Ocean Acidification Program, part of NSF's Science, Engineering and Education for Sustainability programs.

"This research is among the first to identify the links among organism physiology, ocean carbonate chemistry and oyster seed mortality," said Garrison.

Results of the study are online in the journal Geophysical Research Letters, published by the American Geophysical Union.

"From the time eggs are fertilized, Pacific oyster larvae precipitate roughly 90 percent of their body weight as a calcium carbonate shell within 48 hours," said George Waldbusser, an Oregon State University marine ecologist and lead author of the paper.

"Young oysters rely solely on the energy they derive from the egg because they have not yet developed feeding organs."

During exposure to increasing carbon dioxide in acidified water, however, it becomes more energetically expensive for organisms like oysters to build shells.

Adult oysters and other bivalves may grow more slowly when exposed to rising carbon dioxide levels. But larvae in the first two days of life do not have the luxury of delayed growth.

"They must build their first shell quickly on a limited amount of energy--and along with the shell comes the organ to capture external food," said Waldbusser.

"It becomes a death race of sorts. Can the oyster build its shell quickly enough to allow its feeding mechanism to develop before it runs out of energy from the egg?"

The results are important, marine scientists say, because they document for the first time the links among shell formation rate, available energy, and sensitivity to acidification.

The researchers say that the faster the rate of shell formation, the more energy is needed. Oyster embryos building their first shells need "to make a lot of shell on short order," said Waldbusser.

"As the carbon dioxide in seawater increases, but before waters become corrosive, calcium carbonate precipitation requires more energy to maintain higher rates of shell formation during this early stage."

The researchers worked with Whiskey Creek Shellfish Hatchery in Netarts Bay, Ore. They found that on the second day of life, 100 percent of the larval tissue growth was from egg-derived carbon.

"The oyster larvae were still relying on egg-derived energy until they were 11 days old," said Elizabeth Brunner of Oregon State University and a co-author of the paper.

The earliest shell material in the larvae contained the greatest amount of carbon from the surrounding waters.

Increasing amounts of carbon from respiration were incorporated into shells after the first 48 hours, indicating an ability to isolate and control the shell surfaces where calcium carbonate is being deposited.

Waldbusser notes that adult bivalves are well-adapted to growing shell in conditions that are more acidified, and have evolved several mechanisms to do so.

These include use of organic molecules to organize and facilitate the formation of calcium carbonate, pumps that remove acid from the calcifying fluids, and outer shell coatings that protect minerals to some degree from surrounding waters.

Waldbusser said that the results help explain previous findings at the Whiskey Creek Hatchery of larval sensitivity to waters that are high in carbon dioxide but not corrosive to calcium carbonate.

They also explain carryover effects later in larval life of exposure to high carbon dioxide, similar to human neonatal nutrition effects.

The discovery may be good news, scientists say, because there are interventions that can be done at hatcheries that may offset some of the effects of ocean acidification.

Some hatcheries have begun "buffering" water for larvae--essentially adding antacids to incoming waters--including the Whiskey Creek Hatchery and the Taylor Shellfish Farms in Washington.

The study provides a scientific foundation for the target level of buffering.

"You can make sure that eggs have more energy before they enter the larval stage," said Waldbusser, "so a well-balanced adult diet may help larval oysters cope better with the stress of acidified water."

Media Contacts
Cheryl Dybas, NSF (703) 292-7734 cdybas@nsf.gov
Mark Floyd, Oregon State University (541) 737-0788 mark.floyd@oregonstate.edu
Peter Weiss, American Geophysical Union (202) 777-7507 pweiss@agu.org
The National Science Foundation (NSF) is an independent federal agency that supports fundamental research and education across all fields of science and engineering. In fiscal year (FY) 2012, its budget was $7.0 billion. NSF funds reach all 50 states through grants to nearly 2,000 colleges, universities and other institutions. Each year, NSF receives about 50,000 competitive requests for funding, and makes about 11,500 new funding awards. NSF also awards about $593 million in professional and service contracts yearly.

Cheryl Dybas | EurekAlert!
Further information:
http://www.nsf.gov

More articles from Ecology, The Environment and Conservation:

nachricht Joint research project on wastewater for reuse examines pond system in Namibia
19.12.2016 | Technische Universität Darmstadt

nachricht Scientists produce a new roadmap for guiding development & conservation in the Amazon
09.12.2016 | Wildlife Conservation Society

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

Im Focus: How to inflate a hardened concrete shell with a weight of 80 t

At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).

Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...

Im Focus: Bacterial Pac Man molecule snaps at sugar

Many pathogens use certain sugar compounds from their host to help conceal themselves against the immune system. Scientists at the University of Bonn have now, in cooperation with researchers at the University of York in the United Kingdom, analyzed the dynamics of a bacterial molecule that is involved in this process. They demonstrate that the protein grabs onto the sugar molecule with a Pac Man-like chewing motion and holds it until it can be used. Their results could help design therapeutics that could make the protein poorer at grabbing and holding and hence compromise the pathogen in the host. The study has now been published in “Biophysical Journal”.

The cells of the mouth, nose and intestinal mucosa produce large quantities of a chemical called sialic acid. Many bacteria possess a special transport system...

Im Focus: Newly proposed reference datasets improve weather satellite data quality

UMD, NOAA collaboration demonstrates suitability of in-orbit datasets for weather satellite calibration

"Traffic and weather, together on the hour!" blasts your local radio station, while your smartphone knows the weather halfway across the world. A network of...

Im Focus: Repairing defects in fiber-reinforced plastics more efficiently

Fiber-reinforced plastics (FRP) are frequently used in the aeronautic and automobile industry. However, the repair of workpieces made of these composite materials is often less profitable than exchanging the part. In order to increase the lifetime of FRP parts and to make them more eco-efficient, the Laser Zentrum Hannover e.V. (LZH) and the Apodius GmbH want to combine a new measuring device for fiber layer orientation with an innovative laser-based repair process.

Defects in FRP pieces may be production or operation-related. Whether or not repair is cost-effective depends on the geometry of the defective area, the tools...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

Nothing will happen without batteries making it happen!

05.01.2017 | Event News

 
Latest News

Solar Collectors from Ultra-High Performance Concrete Combine Energy Efficiency and Aesthetics

16.01.2017 | Trade Fair News

3D scans for the automotive industry

16.01.2017 | Automotive Engineering

Nanoparticle Exposure Can Awaken Dormant Viruses in the Lungs

16.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>