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Restrictions in Seaweed Agar-vate Scientists

Thursday, December 17th, 2015
Bivalves from Panama for Dermo disease study

Bivalves from Panama for Dermo disease study

by Heather Soulen

Last week Nature magazine published a news piece about how supplies of agar, a research staple in labs around the world, are dwindling. Agar is a gelatinous material from red seaweed of the genus Gelidium, and is referred to as ‘red gold’ by those within the industry. Insiders suggest that the tightening of seaweed supply is related to overharvesting, causing agar processing facilities to reduce production. Most of the world’s ‘red gold’ comes from Morocco. In the 2000s, the nation harvested 14,000 tons per year. Today, harvest limits are set at 6,000 tons per year, with only 1,200 tons available for foreign export outside the country. In typical supply and demand fashion, distributor prices are expected to skyrocket. As a result, things could get tough for scientists who use agar and agar-based materials in their research.

Agar is a scientist’s Jell-O. Just like grandma used to make Jell-O desserts with fruit artfully arranged on top or floating in suspended animation within a mold, scientists use agar the same way. Bacteria and fungi can be cultured on top of nutrient-enriched agar, tissues of organisms can be suspended within an agar-based medium and chunks of DNA can move through an agarose gel, a carbohydrate material that comes from agar. Agar and agar products are the Leathermans of the science world.

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NOAA Grant Funds Hypoxia and Acidification Research in the Chesapeake Bay

Monday, August 9th, 2010
Denise Breitburg holding net and standing in water surveying animals.

SERC senior scientist Denise Breitburg will lead the NOAA-funded study of hypoxia and acidification in the Chesapeake Bay.

Marine ecologist Denise Breitburg and her colleagues have thought up many novel ways to investigate the impacts of dead zones and acidification on Chesapeake Bay fish and invertebrates. Among their ideas: attaching tiny transmitters to fish and monitoring their movement in relation to oxygen and pH levels. A new $1.4 million grant from the National Oceanic and Atmospheric Administration will enable them to pursue this experiment and a host of others.
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Hypoxic waters: Researching beyond the surface to understand the impact on fisheries

Friday, March 19th, 2010

Two summer interns in a boat measuring the water's dissolved oxygen.

Two summer interns measure the water's dissolved oxygen concentrations. Water is typically considered hypoxic if oxygen concentrations are below 2mg/L. Photo: Courtney Richmond

Habitat destruction comes in many forms. The obvious include the clear-cutting of forests and the removal of mountaintops. Then there is the damage that’s less visible, like hypoxia.

In coastal waters around the world there are more than 500 hypoxic zones. These are areas where dissolved oxygen concentrations are so low that they threaten fish, invertebrates and aquatic food webs. Some fish manage to escape hypoxic areas, but oysters, clams and other sessile creatures are simply stuck.

Hypoxia makes the evening news when there’s a noticeable fish kill. However many of its effects are more subtle. Individuals that fail to escape low oxygen zones can suffer mortality or reduced growth and reproduction. Creatures that flee can become easy targets for fishermen and predators.
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