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Gulf-wide study probes seabird deaths

Volunteers from New Jersey to Nova Scotia are playing a key role in helping scientists monitor seabird mortality in a Canadian-American cooperative effort. The organizing groups, Bird Studies Canada (www.bsc-eoc.org) and the Tufts University Seabird Ecological Assessment Network or SEANET (www.tufts.edu/vet/seanet/), each already had volunteers walking local beaches and reporting dead seabirds monthly. More recently they began joint educational sessions to coordinate volunteer training and help standardize data. The goal is to establish long-term monitoring throughout the northeastern United States and Atlantic Canada coasts.

The beached seabird surveys provide baseline information about the current level of beached birds in the region, and could help identify large events such as oil spills, which are particularly devastating to seabirds because the oil degrades their waterproofing and poisons them. The data also may identify other threats such as contaminants, diseases, offshore development and mortality related to fishing gear entanglement.

Bird Studies in Sackville, New Brunswick, recently expanded its efforts beyond Cape Breton and into the Bay of Fundy. “Cape Breton has worked out well, and we want to see if the project will work in the Bay of Fundy,” said Greg Campbell, project biologist for Bird Studies. “The tides are so extreme and there are many cliffs there, so it may be hard to tell how many birds have died.”

SEANET, based at the Tufts University veterinary school in Grafton, Massachusetts, has been operating its program since the fall of 2002. So far more than 300 volunteers have found 34 different species of birds beached. The volunteers fill in a data sheet on what they find, and if the birds are fresh enough, they can bring them in for scientists to examine the cause of death.

Both Harris and Campbell say the primary cause of beached birds is oil from sources including bilge waste and oil spills. “Even a small drop of oil can cause leaks of the bird's feathers, and most will get hypothermia and die,” Harris said.

The project is funded partly through an Action Plan Grant from the Gulf of Maine Council. A SEANET volunteer training session will be held Saturday, September 10, from 1 to 3 p.m. at the Maine Audubon headquarters in Falmouth, Maine. Contact Becky Harris at (508) 887-4933 or becky.harris@tufts.edu.

Poor understanding of global warming

Scientists have found clear evidence of human-produced warming in the world's oceans, but climate change and the threat of global warming remain poorly understood by the U.S. public.

Computer models and real-world data were used to capture signals of the penetration of greenhouse gas warming in the oceans. The findings indicate that ocean warming is produced by human activities, according to researchers at Scripps Institution of Oceanography at the University of California and Lawrence Livermore National Laboratory's Program for Climate Model Diagnosis and Intercomparison.

“This is perhaps the most compelling evidence yet that global warming is happening right now, and it shows that we can successfully simulate its past and likely future evolution,” Tim Barnett, a research marine physicist at Scripps, said at the meeting of the American Association for the Advancement of Science. He and his colleagues used computer models of climate to calculate human-produced warming in the world's oceans over the last 40 years. The models' indications of future climate change have a high enough probability of happening that they need to be taken seriously by decision makers, he adds.

That might be tough, given the United States public's poor understanding of the issue and the low priority policymakers place on taking any actions to reduce human impact, according to a recent study by the Massachusetts Institute of Technology's Laboratory for Energy and the Environment. The results suggest that elected officials rather than public opinion will lead changes in U.S. climate policy. But officials will have a tough time achieving significant reductions of greenhouse gases, the MIT researchers say, because they involve costs higher than what the average consumer is willing to pay.

MIT found that many of the 1,200 people surveyed, the environment ranked 13th on a list of 22 choices for “the most important issues facing the U.S. today.” Of ten specific environmental problems, global warming ranked sixth, behind pollution and toxic waste.

Seaweeds detoxify organic pollutants

Marine seaweeds can detoxify organic pollutants such as trinitrotoluene (TNT) and polycyclic aromatic hydrocarbons, leading researchers to believe they might play an important role in protecting the health of organisms at risk such as clams, shrimp, oysters and crabs that tend to accumulate the dangerous substances.

The findings also may have important implications for the safety of seafood, according to researchers at Oregon State University's College of Engineering and Northeastern University's Marine Science Center. They say one possibility might be to plant a protective buffer of seaweeds around aquaculture areas.

“We found that certain red seaweeds had an intrinsic ability to detoxify TNT that was five to ten times faster than any known terrestrial plant,” Greg Rorrer, a professor of chemical engineering at Oregon State, said at the annual meeting of the American Association for the Advancement of Science. “Marine seaweeds have a more efficient uptake mechanism than even terrestrial aquatic plants to at least neutralize organic pollutants.” The detoxifying process is called “phycoremediation,” derived from the Greek word for seaweed, “phykos.”

The studies were supported by the Office of Naval Research and the Oregon Sea Grant Program, which are concerned about the possibility of corrosion in unexploded bombs or military shells containing TNT that remain in parts of the world's oceans.

Rorrer said it is important to know how corals, fish and plants might respond to exposure to TNT as well as polycyclic aromatic hydrocarbons from motor craft and other sources. Ongoing studies show marine seaweeds process toxins into a less harmful form, and they can do it without harming themselves. It is unclear if there are freshwater plants that can perform a similar function in streams or lakes.

Researchers also are studying the creation of genetically engineered seaweeds that may remove organic contaminants more efficiently.

- Lori Valigra, Assistant Editor

Horseshoe crabs and human blindness

Horseshoe crabs - often called “living fossils” because they have not evolved since the age of the dinosaurs - can tell us how human vision works, according to Dr. Robert Barlow, director of the Center for Vision Research at SUNY Upstate Medical University in Syracuse, New York.

At a lecture at the New England Aquarium in April, Barlow explained how research on crabs is leading to an understanding of the causes underlying human diseases such as macular degeneration.

Barlow has been studying the neural activity that occurs when crabs view their underwater world. Crabs have ten eyes including two lateral compound eyes, which have about 1,000 light receptors that send nerve signals to the brain.

He discovered that crabs are a million times more sensitive to light at night, when mating occurs, than during the day and that circadian rhythmsthe body's internal clockchange the retina's sensitivity over the course of each 24-hour period.

Circadian rhythms also play a role in human vision, only “our vision gets less sensitive at night” when there is a natural lowering of blood glucose levels, Barlow said.

Pilots who fly through the early hours of the morning or marathon runners on the last leg of a race can experience fuzzy vision or blind spots in the center of their visual field because their glucose levels have fallen. Eating a candybar is a quick fix.

For the elderly who suffer from macular degeneration, fuzzy vision and blind spots are a permanent condition. Barlow has been investigating whether glucose plays a role in this disease. Tests on human subjects and mice suggest that there is a link between low glucose levels and diminished vision in the macular regionor centerof the eye.

Barlow, who conducts research at the Marine Biological Laboratory at Woods Hole, Massachusetts during the summers, plans to continue his work on understanding the neural basis of visual behavior.

- Maureen Kelly

“Stubby” Knowles, environmental hero

Robert “Stubby” Knowles who died this past November at 71, was the Gloucester, Massachusetts shellfish warden for over 33 years. During that time he came to be known as “the patriarch” of coastal wetland protection and restoration throughout the region. Knowles maintained fish ladders that allow fish to reach upstream spawning grounds, provided important reports and input for projects impacting coastal areas, and educated students and citizens to foster stewardship of coastal resources. The National Oceanic and Atmospheric Administration recently presented a 2005 Environmental Hero Award to Knowles' family in honor of Stubby's contributions.