Study of stranded dolphins shows many to be near-deaf

Hearing crucial in animals’ ability to feed, navigate!

Rescue workers helped a dolphin on Lieutenant Island in Wellfleet, Mass., in March, when two groups of white-sided dolphins wounded up being stranded on Cape Cod.

(Steve Heaslip/Cape Cod Times via Associated Press)

By David A. Fahrenthold Washington Post

WASHINGTON — New research into the cause of dolphin “strandings’’ — incidents in which weakened or dead dolphins are found near shore — has shown that in some species, many stranded creatures share the same problem.

That understanding — gained from a study of dolphins’ brain activity — could help explain why such intelligent animals do something so seemingly dumb. Unable to use sound to find food or family members, dolphins can wind up weak and disoriented.

Researchers are unsure what is causing the hearing loss: It might be old age, birth defects, or a cacophony of man-made noise in the ocean, including Navy sonar, which has been associated with some marine mammal strandings in recent years.

The news, researchers say, is a warning for those who rescue and release injured dolphins: In some cases, the animals might be going back to a world they can’t hear.

“Rehab is pretty time-consuming and pretty expensive,’’ said David Mann, a professor at the University of South Florida and the study’s lead author. If the dolphin can’t hear, he said, “there’s almost no point in rehabbing it and releasing it.’’

The study, published Nov. 3 in the journal PLoS One, examined several species of marine mammals — including dolphins and small whales — living in the Gulf of Mexico, Atlantic Ocean, and Caribbean Sea. The animals had been found stranded in the wild and taken in for medical treatment and feeding.

Each year, from 1,200 to 1,600 whales and dolphins are found stranded off the US coast, according to the National Oceanic and Atmospheric Administration. The vast majority are dead: In 2007, the most recent year with data, only 195 out of 1,263 animals were found alive.

But many of those also die later or are euthanized on the scene. A few survive but are too young or too debilitated to be returned to the wild.

Of the 195 animals found alive that year, just five were released.

Trying to study what put these animals in distress, the researchers faced a puzzle. How do you test a dolphin’s hearing?
“They can’t raise their flipper’’ if they hear a tone, Mann said.

Instead, researchers looked for reactions to the sound inside the animals’ brains. The researchers affixed sensors to the creatures’ heads with suction cups, which could detect electrical activity in the brain. They then played a series of tones: If the animals could hear them, the sensors would detect millions of neurons firing to process the sound.

In some of the species they studied, the tests showed that stranded animals could still hear normally. Three Risso’s dolphins, two pygmy killer whales, and a spinner dolphin showed no problems.

But the researchers found severe to near-total hearing loss in two species. Among bottlenose dolphins, four out of seven stranded animals had hearing problems. Among rough-toothed dolphins, the total was five out of 14.

That, they said, could be a serious problem for animals that live in often-murky waters. Bottlenose dolphins often use sound to find each other: Each has a “signature whistle’’ all its own.

In addition to hearing sounds made by other creatures, dolphins also use their own sonar to hunt and locate the seafloor and other objects.

Scientists say these rapid-fire sounds — a series of clicks to human ears — return to give the dolphins information about the size and shape of prey.

“These animals are living in an environment where vision can’t play the same role it does on land,’’ said Randall Wells, a senior conservation scientist at the Chicago Zoological Society who was another of the study’s authors. “Sound is probably the most important sense that they have.’’

Without the ability to hear these sounds, scientists said dolphins can be helpless.

© Copyright 2010 Globe Newspaper Company.

Canadians vote against fluoridated water supplies

By Cosmetic Dentistry Guide

Still think your voice doesn’t matter? Think AGAIN!
People aren’t unaware of the benefits of fluoride, my friend – they are AWARE of the damage!!
-Patricia Cori

Residents in Waterloo, Ontario have voted to stop adding fluoride to water supplies.

The decision, which was announced on Tuesday, has been welcomed by anti-fluoride campaigners; however, the news has shocked dentists and the incoming head of the Ontario Dental Association has condemned the decision. Dr Harry Hoediono has criticised the decision, saying that people are unaware of the dental health benefits of fluoride and are voting to stop fluoridation based on flimsy evidence they have downloaded from the internet. Dr Hoediono said that it was a shame that such an important decision could be made by a small group of people who perhaps do not have the necessary knowledge to make an informed decision.

Campaigners against fluoride believe that adding fluoride to the water supply is tantamount to poisoning and are lobbying for fluoridation to be stopped all over Canada. Opponents of fluoride claim the chemical is illegal, unnecessary and dangerous; campaigners believe fluoride contributes to health conditions, including increased risk of cancer, thyroid disease and arthritis.

Public health officials and dentists in the area are outraged by the decision; numerous studies conducted all over the world have consistently shown that fluoride helps to strengthen and protect the teeth, which reduces rates of decay. Fluoride also helps to cut costs for public health services as people are less likely to need dental treatment.
Most councillors were opposed to stopping fluoridation; however, they voted in favour of stopping it to support public opinion. Regional Chairman, Ken Seiling, said he did not believe much of what protestors had to say; however, he claimed that health officials had failed to run an effective campaign, which meant that people were largely unaware of the benefits of fluoride.

Matadors at bullfight dive for safety as half-tonne beast leaps over fence

When, oh when, will human beings stop torturing animals for entertainment?- Patricia Cori


Matadors waiting to take part in a bullfight were left scrambling for their lives when a half-tonne bull jumped a ring-side barrier.

In shocking footage in which the animal appears to target its tormentors, the bull is seen to enter the ring at full gallop before heading straight for a fence which it vaults with ease.

As onlookers scatter, the animal gets a second boost by pushing off the red barrier before finally crashing into a second tier of seating in the Mexican ring.

Entry: The bull is let into the ring at full gallop where it immediately makes a beeline for the crowd

Leap: The animal does not slow down as it heads for the fence, jumping over it with ease

Men watching the fight in Plaza de Toros, Mexico City, were forced to flee but a picador – responsible for spearing the animals during the fights – was hurt.

Landing: The bull smashes into a second tier of seats, causing chaos and fear among spectators

I’ll show you how to horse box! Wild stallions square off in bloody fight for mating rights
In the confusion one man is seen to jump into the ring to escape the beast, then leap straight back when he realises it is about to re-emerge.

The animal then returns to the ring and the fight later continued as planned.

The incident mirrored a similarly horrifying event in Tafalla, Spain, in August when a huge bull jumped an even bigger barrier and started to rampage through the crowd.

At least 40 people were injured in the incident, with a 10-year-old boy suffering serious stomach wounds.

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