August 12, 2005


Small survey planes, daylight and luck have long been the best tools for scientists hoping to spot the rare North Atlantic right whale. The results aren't too impressive.

An estimated one in four whales is spotted by aerial surveys, leaving the rest vulnerable to ship strikes or fishing gear entanglements. But scientists say an underwater listening system they're developing will substantially improve detection and reduce whale deaths.

The "passive acoustic" system would find whales and immediately transmit their location to nearby vessels.

"It will reduce [ship] strikes, period," said Richard Merrick, chief of the protected species branch at NOAA Fisheries, New England.

Only about 350 North Atlantic right whales remain. In the last 14 months, at least eight have been found dead, though scientists recently speculated there could be far more deaths that were never discovered. Four of the known deaths were attributed to ship strikes and one to fishing gear entanglement.

The underwater microphones could enable scientists to pinpoint up to 75 percent of whales in areas they're known to frequent and reduce collisions, Merrick said. It would enable scientists to scan for whales all the time, instead of just in sunlight or good weather. Researchers wouldn't be as dependent on the sometimes dangerous aerial surveys, or the luck needed to be overhead when a whale surfaces.

Scott Kraus, vice president of research at the New England Aquarium, said the listening system seems to work "terrifically," but cautioned it won't solve all the whale's problems. The North Atlantic right whale is quiet compared with crooners like the humpback. It sings to communicate, not as a way to find food, so the noises are less frequent, he said.

Different ages and sexes of the whales may make noise at different times, making the system less effective at spotting them. For instance, Kraus said, new mothers and calves may keep quiet to avoid detection by predators.

The system is at least three years from being fully in place in areas the whales frequent off New England, such as Cape Cod Bay. Complicated negotiations with shipping and fishing interests are needed to ensure vessels will use the new information to change their routes or slow down to avoid a whale.

"Just knowing their whereabouts isn't a conservation act in itself," said Dave Wiley, research director at Stellwagen National Marine Sanctuary off Massachusetts, where several underwater microphones will be deployed over the next year.

-- Associated Press

Did you know...

There are two major types of lung cancer: small cell, which tends to spread widely through the body, and non-small cell. Small-cell lung cancers account for about 13 percent of cases; most of the rest are non-small-cell lung cancers.

-- American Cancer Society

In Brief

Nighttime risk for newborns

While most expectant parents can't control when their baby will arrive, they should cross their fingers that it happens between 7 a.m. and 7 p.m., researchers now believe.

Babies born in the early evening or late at night are much more likely to die in their first four weeks of life than those born during daytime hours, according to a new Stanford University review of more than 3.3 million California births from 1992 through 1997.

The findings were true of big babies and small babies, and those born in large hospitals and small. Even after considering the mother's prenatal care, pregnancy complications and the baby's gender, there were still many deaths with no other risk factor than the time of day the baby was born. The study is in the August issue of the journal Obstetrics and Gynecology.

"This is quite real," said Dr. Jeffrey B. Gould, the study's main author and director of the perinatal epidemiology and health outcomes research unit at Stanford. "The question is, what is causing this, specifically, and what can we do about it?" he said.

While the superstitious might attribute the difference to astrology, numerology or perhaps even circadian rhythms, Gould said hospitals are the primary suspects. "There may be some hospitals that are really stressed at night in being able to meet patients' needs," he said.

Growing up overweight

Overweight girls reach puberty earlier, but early puberty alone doesn't necessarily lead to being overweight in adulthood, according to a new study. Instead, it's childhood pudginess that's linked with both early menstruation and adult weight problems.

Girls who were overweight before their first menstrual periods were almost eight times more likely to be overweight as women, the study found. But there was no link between precocious puberty alone and being overweight later in life.

"Given the epidemic of obesity in the population, it's important to know where best to intervene," said lead researcher Aviva Must, associate professor of public health and family medicine at Tufts University School of Medicine in Boston. That intervention should start in childhood, she said.

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