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Fences Could Help Clean Up Watercourses

9/20/10

Building good fences could make our water cleaner, and help us to meet European standards, according to researchers working on the UK research councils' Rural Economy and Land Use Programme (Relu).

Relu scientists have created a computer model to investigate the problem of fecal pollution in UK rivers. The organisms come mainly from farm animals' feces and untreated human sewage.

As sewage treatment has improved over recent years, human sewage is less problematic, except in times of heavy rainfall, when less efficient treatment works pose a threat. But livestock, and dairy cattle in particular, continue to be a major contributor of harmful organisms. The research shows that there is a high risk of fecal pollution entering watercourses within areas with high densities of dairy cattle.

The UK has to tackle this problem, not only because of the health risks for those such as canoeists and paddlers, especially children, who are directly exposed to pollution in rivers, but also because of European legislation. At the moment, many of our watercourses do not meet the requirements of the European Water Framework Directive.

One way of reducing the numbers of fecal organisms would be to have fewer farm animals grazing in vulnerable areas near rivers. But, for some dairy farmers, a reduction in stocking densities could have serious implications for their livelihoods and there could be economic consequences for wider rural communities.

So, drawing on work from several projects across the Relu research program, the team created a computer model to investigate different approaches to tackling the problem. These included government interventions that would directly restrict stocking levels and simpler, everyday solutions, such as erecting fences to prevent livestock depositing feces directly into watercourses.

They found that simple farm-scale solutions are likely to be most effective at reducing the numbers of potentially dangerous organisms entering watercourses -- and could work out cheaper both for farmers and consumers.

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Monterey sea otters killed by toxic algae

9/13/10

A toxic algae that forms in reservoirs, lakes and stagnant freshwater ponds was responsible for the deaths of at least 21 threatened California sea otters in the Monterey Bay area, a scientific study revealed Friday.

The discovery, reported in the scientific journal PLoS ONE, is alarming because the toxin, called microcystin, had never been linked to the death of a marine mammal and was not believed to be capable of surviving for long periods in saltwater.

"Based on what we know, this is the first documentation of a freshwater algal bloom being transmitted to upper-level marine mammals, specifically a federally listed species," said Melissa Miller, a senior wildlife veterinarian and pathologist for the California Department of Fish & Game and the study's lead author.

The three-year average population of California otters, also known as southern sea otters, declined 3.6 percent this year, the second consecutive drop after a decade of increases. The reason for the decline is a mystery, but scientists believe a variety of causes are at play, including toxic runoff.

Microcystin, which is commonly referred to as blue-green algae, can cause liver damage when ingested. All 21 sea otters that tested positive for the bacteria died from liver failure, according to the study, which was completed with the help of experts from UC Santa Cruz and a variety of state and federal agencies.

It is believed the toxins flowed to the ocean off the coast of Monterey in rivers and creeks. Sea urchins and shellfish near the outflow filtered the water and the poison accumulated in their bodies, which were, in turn, eaten by otters.

Microcystis is a naturally occurring algae. Its bright green blooms have long been found behind dams, particularly along the Klamath River, and in stagnant pools.

But researchers say the microcystin toxin appears to be multiplying in the environment to the point that it is becoming a global health concern. That's because cyanobacteria, as scientists call bacterial blooms, thrive in warm water that is rich in nutrients from lawn, city and agricultural runoff. The warmer the temperatures, the more bacteria there are

Global warming, scientists say, has increased the frequency of deadly green "super-blooms."

Microcystins have been detected in brackish water before, including in the Sacramento-San Joaquin River Delta and San Francisco Bay, scientists say. The bacteria has been linked to the death of cattle and even dogs that drank the water or swam through the green slime and then licked their fur. It is also potentially dangerous to humans.

"What's really astonishing to us is that it had not been on anyone's radar as a problem in the marine environments until now," said co-author Tim Tinker, a research biologist with the U.S. Geological Survey and an adjunct professor of ecology and evolutionary biology at UC Santa Cruz.

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Will FDA Approve Genetically Modified Salmon?

9/7/10

Transcript:

MELISSA BLOCK, host:

Will the Food and Drug Administration approve the first genetically modified animal for human consumption? The animal is a genetically engineered salmon that grows to market size twice as fast as conventional salmon. And the FDA will be holding public meetings about that fish starting on September 19th.

The company behind the salmon, AquaBounty Technologies, got a thumbs-up last week from a panel of FDA scientists. They concluded there is a reasonable certainty of no harm from consumption of food from this animal.

So what should we know about this fish and its future? Professor Anne Kapuscinski is a fisheries biologist at Dartmouth College. She has studied both endangered salmon and genetically modified fish. Welcome to the program.

Professor ANNE KAPUSCINSKI (Professor of Sustainability Science, Dartmouth College): Thank you for having me.

BLOCK: And why don't you explain first how this salmon has been genetically modified to grow faster?

Prof. KAPUSCINSKI: The company that's developed these fish has inserted two genes. One gene is for growth hormone, and it's almost identical to the growth hormone gene that's already in these salmon.

And then the other gene acts like a little switch. It's a piece of DNA that comes from another fish, from the ocean pout, and it's normally connected to the gene that produces antifreeze protein in that fish.

In the case of these salmon, they've just taken the part of the DNA that acts like a switch, and that switch turns on the gene that produces the growth hormone so that the salmon will produce growth hormone in its tissues throughout the year, whereas a conventional salmon only produces growth hormone during the warmer times of the year, when the water temperatures are warmer.

BLOCK: So they end up growing to market size in, what, 18 months instead of three years.

Prof. KAPUSCINSKI: I think that's about right. It's about half the time.

BLOCK: When the FDA studies this genetically modified salmon to see whether it's safe to eat, what are they looking at? How do they make that decision?

Prof. KAPUSCINSKI: The FDA asked the company to present data on several issues. First of all, is the inserted gene safe for the health of the animal? Is the inserted gene and the growth hormone it's producing safe for humans to eat the fish? And third, will the farming of these fish have any effects on the environment?

They are not required to conclude that they're environmentally safe, and that's the only condition under which to approve them. That law just requires an environmental assessment, basically figuring out what would be the effect on the quality of the human environment.

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Dead zones a coastal threat

9/3/10

Dead zones increased dramatically in U.S. waters over the past 50 years, threatening ecosystems and fisheries nationwide, according to a sweeping report Friday by the federal Office of Science and Technology Policy.

The multiagency assessment said that incidents of hypoxia — a condition in which oxygen levels drop so low that fish and other animals are stressed or killed — have risen nearly 30-fold since 1960 due in part to man-made pollutants.

It called for renewed efforts to reduce water pollutants that lead to low levels of dissolved oxygen and improve strategies to protect marine food sources.

A dead zone in San Diego Bay, first documented in the 1980s, was part of the analysis. Scientists have used it for years as an example of an oxygen-starved area where runoff from cities contributes to hypoxic conditions.

“There are reasons to worry about San Diego Bay, but hypoxia hasn’t been studied as rigorously here as it has in other places like the Chesapeake Bay, where it is a much bigger problem,” said Brian Hentschel, a biology professor at San Diego State University who studies bottom-dwelling organisms such as worms, clams and shrimps.

He hopes Friday’s national assessment spurs more funding for local research that tracks dissolved oxygen and related factors across San Diego Bay over time.

“That report should trigger some alarm bells because it’s pretty clear that the human impacts that create hypoxic conditions have been increasing,” Hentschel said. “More detailed data now will make it easier 15 or 20 years from now to know how the bay is changing.”

Dead zones were detected in nearly half of the 647 waterways assessed. On the West Coast, federal researchers found a sixfold increase in the number of dead zones over the past 20 years, with 37 areas now suffering from low oxygen. A region off the coast of Oregon and Washington has become the second-largest seasonal hypoxic region in the United States and third largest in the world.

Friday’s report said work to study and control pollutants are advancing but management efforts to stem the tide of hypoxia “have not made significant headway” in part due to increased development and population growth in coastal watersheds.

“If current practices are continued, the expansion of hypoxia in coastal waters will continue and increase in severity, leading to further impacts on marine habitats, living resources, economies, and coastal communities,” the report’s authors said.

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California Plastic Bag Ban Rejected By State Lawmakers

9/1/10

California lawmakers have rejected a bill seeking to ban plastic shopping bags after a contentious debate over whether the state was going too far in trying to regulate personal choice.

The Democratic bill, which failed late Tuesday, would have been the first statewide ban, although a few California cities already prohibit their use.

The measure offered California an opportunity to emerge at the forefront of a global trend, said Sen. Gil Cedillo, who carried the measure on the Senate floor.

"If we don't solve this problem today, if we don't create a statewide standard, if we don't provide the leadership that is being called for, others will," the Los Angeles Democrat said during Tuesday evening's debate.

Discouraging plastic bag use through fees or bans first gained traction outside of the U.S. in nations such as South Africa, Ireland, China and Bangladesh. In January, Washington, D.C., implemented a 5-cent surcharge on disposable paper and plastic bags.

A handful of California cities already ban single-use plastic bags, after San Francisco became the first to do so in 2007.

Palo Alto, Malibu and Fairfax in Marin County have since followed, while a ban approved in Manhattan Beach is tied up in litigation, said Matthew King, a spokesman for Heal the Bay, the Santa Monica-based nonprofit that sponsored AB1998.

Supporters of the bill said the 19 billion plastic bags state residents use every year harm the environment and cost the state $25 million annually to collect and transport to landfills. It had been the subject of a furious lobbying campaign by the plastic bag manufacturing industry, which called it a job killer.

The bill's author, Democratic Assemblywoman Julia Brownley of Santa Monica, said lawmakers had failed Californians by defeating the measure. But she said the movement to ban plastic bags would continue despite the setback.

The bill's main opponent, the Virginia-based American Chemistry Council, spent millions in lobbying fees, radio ads and even a prime-time television ad attacking the measure. The organization represents plastic bag manufacturers such as Dow Chemical Co. and ExxonMobil Corp.

Last year, it helped defeat an effort by Seattle to impose a 20-cent fee on the use of plastic or paper grocery bags.

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