Beached Dolphins Are Often Deaf

In a fascinating study published on November 3 in the journal PLoS One, researchers looking into the cause of dolphin strandings found that in some species, many of these stranded creatures are nearly deaf.

That finding, which scientists gained from a study of the brain activity of the dolphins, could explain why such intelligent animals do something that appears pretty stupid: land themselves on a beach. Unable to use sound to find food or family members, these dolphins are often weak and disorientated.

Around 1,500 Whales And Dolphins Stranded Every Year

Every year, 1,200 to 1,600 whales and dolphins are found stranded off the U.S. coast, according to the National Oceanic and Atmospheric Administration. Most are dead and of the rest, many are euthanized on the scene or die later.

But how did they become deaf? These same researchers are unsure of that answer, but suggest that it might be old age, birth defects, or perhaps Navy sonar, which has been associated with several marine mammal strandings recently. (Click here for a report on the recent beaching of 33 pilot whales off County Donegal, Northern Ireland.)

Is Too Much Noise Making Them Deaf?

Other researchers have also identified another issue, connected to this one: too much noise in general in the ocean. Dolphins evolved when the only source of loud sounds underwater would have been thunderstorms, or occasionally volcanic eruptions.

Nowadays, however, there are the sounds of powerboats and huge oceangoing ships, in addition to oil and gas explorations that use loud noises to conduct seismic tests of the seabed.

Check Out The Dolphins’ Hearing!

Whatever the reason for their deafness, David Mann, the study’s leading author, who is a professor at the University of South Florida, hopes that his research will encourage organizations that rescue stranded dolphins to give the animals hearing tests. If the animals are found to have serious hearing damage, he said, he suggests that they might be kept at aquariums or other protected locations.

“If the dolphin can’t hear, Mann stated, “there’s almost no point in rehabbing and releasing it” because it probably won’t survive very long.

Why So Many Deaf Dolphins?

It seems that more effort should go into examining the causes of this deafness. Could it be that humans are once again upsetting the natural balance of the earth?

Creative Commons - J.D. Ebberly


colleen p.
colleen p6 years ago

Janine H.

some "primitave cultures" still hunt for meat to. Aborigonal Australians are still killing kangaroo for food

Penelope Bassett-Scarfe

Another reason I heard just recently, was that our Planet is shifting, for instance Tampa International Airports runway in USA had to be closed while they adjusted to the new magnetic north, which was 10 degrees difference, dolphins whales etc use their sonar and they tune into the earths magnetic fields, and because these are changing they are having problems. The other thing is there are so many dead zones in our oceans now, so much rubbish and pollution, I know I would not like to live in amongst all that garbage, and they may be gasping for air or trying to make a BIG statement to us, after all, they are highly intelligent sentient beings, they have a bigger brain than humans

Janine H.
Janine H6 years ago

This is a very sad story. An other animal has to go only because "we" humans do not want to share the world with other life forms, these life forms "we" would not eat (vegetarian food is not a bad idea, or eating with conscience as the so called primitive cultures did and still do, if they still exist. No meat/fish every day).

As little child i thought that rain is when God and the angels cry - because "we" humans have forgotten that we need this "intelligence", someone who could help... if "we" hadn't turned away for many centuries ago...

"Only when the last tree has been cut down; Only when the last river has been poisoned; Only when the last fish has been caught; Only then will you find that money cannot be eaten."
(Native American proverb)

"We have learned to fly the air like birds and swim the sea like fish, but we have not yet learned the simple art of living together as brothers." (Martin Luther King)

Carla Manning
Carla M7 years ago

So, so sad. I do know from experience with dolphins that the noise of a regular motorboat doesn't confuse or scare them. They actually seem to like it and like to swim and show off along the sides of the boat:) But I am all for noise restrictions to keep them safe. Please start a petition for this.

charmaine c.
Charmaine C7 years ago

Very good research. Interesting article. Thank you.

Barbara Erdman
Barbara E7 years ago

Oh no! :-(

Savannah Ford
Savannah F7 years ago

poor dolphins

Michelle R.
Michelle R7 years ago

Dolphins don't beach themselves. If you can't communicate and stay with your would be on the outs. And, dolphins are social, swimming in schools.

Amber M.
Amber Beasley7 years ago

aww =/

Loo Samantha
Loo s7 years ago

thanks for the sad article.