US aircraft bombard Guam with thousands of mice

Published time: December 04, 2013 19:39

The view on Tumon Bay, Guam (Reuters)

Jumping out of a plane and into enemy territory, hanging from custom-made parachutes, lying in wait for your enemies: It’s probably the most nerve-wracking experience anyone can have – unless you’re already dead and stuffed with painkillers.

That’s essentially the situation that unfolded in Guamon Sunday, when the United States bombarded the island with 2,000 dead mice for the fourth time, all in an effort to lure in and kill off the territory’s invasive brown tree snake.

Attached to small cardboard parachutes, the dead rodents floated down over the forest canopy near Anderson Air Force Base, where they’re expected to attract brown tree snakes looking for an easy meal. As with anything that sounds too good to be true, however, the snakes are in for a rude awakening: Each mouse has been filled with acetaminophen, commonly found in Tylenol, which is deadly to the reptiles even in small doses.

“We are taking this to a new phase,” Dan Vice, an assistant state director of the U.S. Department of Agriculture’s Wildlife Services, said to the Associated Press. “There really is no other place in the world with a snake problem like Guam.”

Vice also told KUAM News that the acetaminophen dosage does not pose a risk to other animals, saying that a pig or dog would be safe unless they ate at least 500 of the stuffed mice. The snakes, on the other hand, are expected to die within 72 hours of ingesting a mouse.

The brown tree snake – suspected to have arrived on the island via poorly inspected cargo shipments during the 1950s – may not be a danger to humans, but it has caused numerous problems since it established itself in Guam. As RT reported previously, the snakes have endangered or wiped out nearly all of the island’s native bird species, indirectly affecting even the local tree population that benefits from birds spreading seeds.

In addition to the toll enacted on wildlife, NBC News reported the snakes cause about 80 electrical outages a year when they slither into electrical substations. The cost of repair and lost productivity numbers around $ 4 million annually. Reports of the reptiles biting humans are also on the rise, though their venom is not lethal.

Estimates indicate that more than 2 million brown tree snakes inhabit Guam, with as many as 13,000 per square mile in some areas. While other methods have proved inadequate, U.S. officials are hoping to expand the mice-dropping program across the island if it’s deemed successful.

Containing the snakes has become a priority for Vice, who has said in the past that it’s “inevitable” the animals will eventually reach Hawaii, some 3,000 miles away from Guam, where they could inflict up to $ 2.14 billion in economic damages in addition to damaging local wildlife populations.

Despite the risks, however, the plan to “bomb” the island with dead rodents has caused a stir among animal rights activists. It has drawn condemnation from People for the Ethical Treatment of Animals, which would prefer the snakes to be captured and humanely euthanized.

“Brown tree snakes did not ask to be stowaways on planes or ships and then forced to survive on a foreign island,” Martin Mersereau, director of PETA’s cruelty investigations, said in February.

“Although the snakes are considered invasive, no animal should be forced to endure cruel death,” he added.

RT – USA

US aircraft bombard Guam with thousands of mice

Insulin levels wax and wane daily

Modern life may clash with hormone’s natural cycle

By Tina Hesman Saey

Web edition: February 22, 2013

Like the sun, insulin levels rise and fall in a daily rhythm. Disrupting that cycle may contribute to obesity and diabetes, a new study suggests.

Many body systems follow a daily clock known as a circadian rhythm. Body temperature, blood pressure and the release of many hormones are on circadian timers. But until now, no one had shown that insulin — a hormone that helps control how the body uses sugars for energy — also has a daily cycle. Working with mice, researchers at Vanderbilt University in Nashville have found that rodents are more sensitive to insulin’s effects at certain times of day. Disrupting the animals’ circadian timers interferes with the hormone’s daily rise and fall and makes mice prone to obesity.

If the findings hold up in humans, they could help explain why people who work night shifts tend to be overweight and suffer health problems. The discovery may also tie the obesity epidemic in part to staying up late and eating at the wrong time.

Many people had thought that it was best for the body to maintain insulin at a relatively constant level, says Carl Johnson, a circadian biologist who led the new study. “But that’s not how organisms have adapted,” he says. Since the environment cycles through light and dark, body processes often coordinate with that rhythm.

To uncover insulin’s natural rhythm, Johnson and his colleagues performed an “insulin clamp” procedure on mice. The clamp infuses glucose or insulin around the clock into mice that are moving freely in their cages. Measuring how much insulin or glucose the mice need to maintain constant blood sugar levels tells the researchers how responsive the animals are to the hormone at any given time of day.

Mice are naturally less sensitive to insulin during the day, when the nocturnal animals normally sleep, the team found.

Mice with a genetic flaw that breaks their circadian clock don’t follow the regular insulin cycle. Neither do mice whose circadian clocks have been disrupted by living in constant light. Both groups of animals are more resistant to insulin than normal mice are, the researchers discovered. Insulin resistance is one hallmark of diabetes.

Mice with broken clocks also became obese despite eating the same amount as other mice. The team then found that feeding normal mice a high-fat diet could throw off their circadian rhythms.

The findings suggest that timing meals to coincide with insulin sensitivity could help protect against diabetes, says Satchidananda Panda, a geneticist and biologist at the Salk Institute for Biological Studies in La Jolla, Calif. Chronically mistimed clocks could contribute to insulin resistance and eventually lead to diabetes, he says.

People who hope to bend their biological clocks to fit modern lifestyles are probably out of luck, says neuroscientist Randy Nelson of the Ohio State University Wexner Medical Center. After billions of years of adapting to the world’s natural rhythms, he says, “We’re stuck with these clock genes and these metabolic processes. Electric lights, that’s what’s strange.” Besides avoiding after-dinner snacks, people might protect their body clocks by using dim red lights at night. Red light doesn’t confuse the circadian clock the way bright white or blue lights do.

But Johnson warns that it is early to apply his findings directly to humans. He says eating the main meal at lunch time and not eating overnight are probably healthful practices, but people shouldn’t expect to lose a lot of weight by just shifting when they eat. Poor diet and lack of physical activity are the main drivers of obesity, he says.

Science News

Insulin levels wax and wane daily