Requiem for Baiji, SOS for cousins

[Guest guest]

http://www.telegraphindia.com/1070903/asp/knowhow/story_8266680.asp

 

Monday, September 03, 2007

 

Requiem for Baiji, SOS for cousins

Dolphin experts from across the world join hands to save the Gangetic River

Dolphin from extinction. ** reports

 

Baiji, the Goddess of the Yangtze, is believed to be extinct. An intensive

six-week search by experts in late 2006 failed to find any trace of the

dolphin in its riverine habitat in China. And while a scientist claimed to

have seen a Baiji last week in central China, the sighting has not been

officially confirmed.

 

The disappearance has shaken scientists and conservationists all over the

world — one of the reasons why Baiji's cousins are now under the scanner.

And among them is the Gangetic River Dolphin, found in the Ganga,

Brahmaputra, Meghna and Karnaphuli and their tributaries as well as in

Nepal.

 

" There are three species of river dolphins left — the Indus Dolphin, the

Gangetic River Dolphin and the Bouto of the Amazon, " says R.K. Sinha of the

department of zoology at Patna University, who has studied the Gangetic

River Dolphin for more than a decade.

 

Conservationists are trying their best to save the Gangetic River Dolphin.

WWF-India — along with the Indian Institute of Technology (IIT), Delhi, and

the University of Tokyo — has launched a project to study the river dolphins

of India and monitor their population. " Our survey, covering more than 5,000

km of the Ganga and its tributaries, reveals that there are an estimated

2,000 Gangetic River Dolphins in India, " says Sandeep Behera, coordinator,

Freshwater Species and Wetlands programme, WWF-India.

 

The project also uses a novel method to analyse the underwater sounds of the

mammal by using hydrophones, a device which enables scientists to hear them.

" Gangetic River Dolphins are blind and emit ultrasonic sounds to aid

movement. By using a hydrophone to capture these calls, we hope to better

understand their behaviour, " says Behera.

 

Though it was discovered in 1942 that dolphins use sounds for navigation and

finding prey, there is much that remains to be understood. These animals

emit a beam of clicks that brings forth two kinds of results. " One beam

gives the dolphins a fuzzy response regarding the river environment while

the other is reflected by a projection of the back of the upper jaw that

provides the creature with a clear perception of what lies in front of their

open mouths, " elaborates Sinha.

 

" The hydrophone is a composite pen-like gadget that can detect the

individual clicks of a dolphin from within a range of a few hundred metres, "

says Rajendra Bahl, team researcher and professor of electronics and

acoustics at IIT, Delhi . According to Bahl, this method allows them to

monitor river dolphins day and night in a non-invasive manner. " It is better

than visual counts since the animals spend 90 per cent of their time

underwater, " he says.

 

The hydrophone system is also being used to monitor Irrawaddy dolphins in

the Chilika lake in Orissa. " We have characterised the clicks of the

dolphins and developed technology that enables us to locate the creature and

find out precise details of its communication methods, " says Bahl.

 

Dolphins also use echoes to hunt and stay away from danger. " By bouncing

sounds off an underwater object and analysing the signal they receive, they

can accurately locate an object and determine where it is moving and if it

is alive, " says Sinha.

 

" The present and future of the Gangetic River Dolphin seem to be getting

worse by the day, " says Azam Siddiqui, a wildlife researcher in Assam. The

animals are being poached for their oil, while sand quarries along the Kulsi

river that flows into the Brahmaputra are posing a threat to their

movements.

 

B.C. Choudhary, a scientist at the Wildlife Institute of India, Dehra Dun,

is equally concerned. " Industrial plans to start oil exploration in the

Brahmaputra will further exacerbate the problem, " he says.

 

Dolphins migrate locally and the construction of dams and barrages restrict

their movement. The animal is also a slow breeder with only one calf being

born after a gestation period of 10 months, and this after an interval of

two to three years. " The low birth rate means the regeneration of the

dolphin population is slow, " points out Sinha. And captive breeding to save

this species is not an option as it does not thrive in captivity.

 

Adding to the woes are regular reports of these creatures being killed and

influx of pollutants into the rivers. The Gangetic River Dolphin is an

indicator species — a healthy population shows the availability of fish and

also helps to determine the level of pollutants and toxicity of the water.

Pesticides particularly implicated in environmental and health hazards are

those belonging to the organochlorides group and, among these, DDT and its

metabolites are the most prominent ones that are found deposited in the

dolphins' bodies, says Sinha.

 

The WWF-IIT-University of Tokyo team studied the acoustic beam

characteristics of an isolated Gangetic River Dolphin that was found in

Budhabalanga river in Orissa. This was followed by research on sounds

emitted by these mammals in the Ganga near Narora in Uttar Pradesh.

 

Conservationists and scientists hope that further studies will lead to new

approaches to save the dolphin, also called " a living fossil " as it has

remained unchanged for almost 20 million years. " We hope to continue our

work with WWF India and the University of Tokyo and keep them informed about

the movement of these animals, " says Bahl.

 

If these efforts succeed, the Gangetic River Dolphin may just escape

figuring in the list of extinct species.

 

 

 

[Guest guest]

Great article and congratulations . Its a dramatic and clear

telling which will hopefully get people to pause and think. Here is the

link re the scientists (that your article mentioned in the first

paragraph) who claimed to see the Baiji last week

http://www.planetark.com/dailynewsstory.cfm/newsid/44012/story.htm

 

 

 

-

 

-- In aapn , " "

wrote:

>

> http://www.telegraphindia.com/1070903/asp/knowhow/story_8266680.asp

>

> Monday, September 03, 2007

>

> Requiem for Baiji, SOS for cousins

> Dolphin experts from across the world join hands to save the Gangetic

River

> Dolphin from extinction. ** reports

>

> Baiji, the Goddess of the Yangtze, is believed to be extinct. An

intensive

> six-week search by experts in late 2006 failed to find any trace of

the

> dolphin in its riverine habitat in China. And while a scientist

claimed to

> have seen a Baiji last week in central China, the sighting has not

been

> officially confirmed.

>

> The disappearance has shaken scientists and conservationists all over

the

> world — one of the reasons why Baiji's cousins are now under the

scanner.

> And among them is the Gangetic River Dolphin, found in the Ganga,

> Brahmaputra, Meghna and Karnaphuli and their tributaries as well as in

> Nepal.

>

> " There are three species of river dolphins left — the Indus

Dolphin, the

> Gangetic River Dolphin and the Bouto of the Amazon, " says R.K. Sinha

of the

> department of zoology at Patna University, who has studied the

Gangetic

> River Dolphin for more than a decade.

>

> Conservationists are trying their best to save the Gangetic River

Dolphin.

> WWF-India — along with the Indian Institute of Technology (IIT),

Delhi, and

> the University of Tokyo — has launched a project to study the

river dolphins

> of India and monitor their population. " Our survey, covering more than

5,000

> km of the Ganga and its tributaries, reveals that there are an

estimated

> 2,000 Gangetic River Dolphins in India, " says Sandeep Behera,

coordinator,

> Freshwater Species and Wetlands programme, WWF-India.

>

> The project also uses a novel method to analyse the underwater sounds

of the

> mammal by using hydrophones, a device which enables scientists to hear

them.

> " Gangetic River Dolphins are blind and emit ultrasonic sounds to aid

> movement. By using a hydrophone to capture these calls, we hope to

better

> understand their behaviour, " says Behera.

>

> Though it was discovered in 1942 that dolphins use sounds for

navigation and

> finding prey, there is much that remains to be understood. These

animals

> emit a beam of clicks that brings forth two kinds of results. " One

beam

> gives the dolphins a fuzzy response regarding the river environment

while

> the other is reflected by a projection of the back of the upper jaw

that

> provides the creature with a clear perception of what lies in front of

their

> open mouths, " elaborates Sinha.

>

> " The hydrophone is a composite pen-like gadget that can detect the

> individual clicks of a dolphin from within a range of a few hundred

metres, "

> says Rajendra Bahl, team researcher and professor of electronics and

> acoustics at IIT, Delhi . According to Bahl, this method allows them

to

> monitor river dolphins day and night in a non-invasive manner. " It is

better

> than visual counts since the animals spend 90 per cent of their time

> underwater, " he says.

>

> The hydrophone system is also being used to monitor Irrawaddy dolphins

in

> the Chilika lake in Orissa. " We have characterised the clicks of the

> dolphins and developed technology that enables us to locate the

creature and

> find out precise details of its communication methods, " says Bahl.

>

> Dolphins also use echoes to hunt and stay away from danger. " By

bouncing

> sounds off an underwater object and analysing the signal they receive,

they

> can accurately locate an object and determine where it is moving and

if it

> is alive, " says Sinha.

>

> " The present and future of the Gangetic River Dolphin seem to be

getting

> worse by the day, " says Azam Siddiqui, a wildlife researcher in Assam.

The

> animals are being poached for their oil, while sand quarries along the

Kulsi

> river that flows into the Brahmaputra are posing a threat to their

> movements.

>

> B.C. Choudhary, a scientist at the Wildlife Institute of India, Dehra

Dun,

> is equally concerned. " Industrial plans to start oil exploration in

the

> Brahmaputra will further exacerbate the problem, " he says.

>

> Dolphins migrate locally and the construction of dams and barrages

restrict

> their movement. The animal is also a slow breeder with only one calf

being

> born after a gestation period of 10 months, and this after an interval

of

> two to three years. " The low birth rate means the regeneration of the

> dolphin population is slow, " points out Sinha. And captive breeding to

save

> this species is not an option as it does not thrive in captivity.

>

> Adding to the woes are regular reports of these creatures being killed

and

> influx of pollutants into the rivers. The Gangetic River Dolphin is an

> indicator species — a healthy population shows the availability of

fish and

> also helps to determine the level of pollutants and toxicity of the

water.

> Pesticides particularly implicated in environmental and health hazards

are

> those belonging to the organochlorides group and, among these, DDT and

its

> metabolites are the most prominent ones that are found deposited in

the

> dolphins' bodies, says Sinha.

>

> The WWF-IIT-University of Tokyo team studied the acoustic beam

> characteristics of an isolated Gangetic River Dolphin that was found

in

> Budhabalanga river in Orissa. This was followed by research on sounds

> emitted by these mammals in the Ganga near Narora in Uttar Pradesh.

>

> Conservationists and scientists hope that further studies will lead to

new

> approaches to save the dolphin, also called " a living fossil " as it

has

> remained unchanged for almost 20 million years. " We hope to continue

our

> work with WWF India and the University of Tokyo and keep them informed

about

> the movement of these animals, " says Bahl.

>

> If these efforts succeed, the Gangetic River Dolphin may just escape

> figuring in the list of extinct species.

>

>

>