Among all the species of birds, vultures play a very important role in protecting the environment. The vultures consume dead animals and by doing so help prevent diseases that could wreck havoc on Earth. Any threat to the bio-diversity causes the rapid decline in the population of vultures. Thus the ornithologists are trying to find out all the causes behind the dwindling population of vultures.
Bio-diversity refers to genes species and ecosystem of a region. It refers to the relationship between the species and their habitats. Species are the distinct units of diversity. Each species plays a unique role in ecosystem. Vultures are one such species which plays a very important role in protecting the bio-diversity.
Vultures are the scavenging birds. They feed mostly on the carcasses of animals. Vultures do not kill animals but by consuming the dead animals, they keep the environment clean. Thus, the vultures prevent spread of dangerous diseases like rabies and anthrax, which could play havoc to the wildlife, like stocks and humane. In the absence of any alternative mode of disposal of animals carcasses, they continue to be disposed off in the open. Thus leading to increased risk of rabies and live stock born diseases like anthrax.
The vulture play a very important role in protecting the traditional customs of parsis. The parsis place their dead in ‘Tower of silence’ for vultures to feed upon. Each species of vulture is adapted to feed on particular part of dead animals. this prevents competition between vultures species in places where their ranges overlap.
Thus the vultures play a key ecological role in our bio-diversity. Any threat to biodiversity posses immense threat to the survival and, well being of mankind. However, to day our bio-diversity is facing a typical problem – that is the rapid decline in the vulture population, The scientists, environmentalist are concerned with finding out the causes of rapid decline of vulture population and the ways to overcome the problem so as to protect the bio-diversity from any danger on account of the rapid decline of vulture population.
Almost two decade ago, the vulture were found in plenty near cities, towns, villages, open area, scrubby jungles and scattered tall trees. However in 80’s the gradual decline in vulture population was observed by the environmentalists. The decline of vulture population started assuming alarming proportion. Today these scavenging bird are hardly seen at the places where they were seen in large numbers. So the scientists world over have focused their attention to protect and preserve this important species playing a vital role for the mankind.
The important characteristics of vultures are. They are large sized bird having a wingspan of about 3 meters. and weight about 10 kgs. The vultures have bald head, and hooked the blade and neck of the vulture allows the head to be pushed inside the carcass without getting the feather bloody and messy.
The vultures have such weak bills that their food must be partly rotted before they can tear the flesh. The vultures are gregarious birds with groups perching for long period around the feeding areas. They feed entirely on the carrion by way of scavenging for carcasses by soaring. A flock of vultures can clean a carcasses of dead bullock within 30 to 40 minutes. Thus the vultures help cleaning the vicinity from the dirt and danger of any epidemic breaking out due to the dead bodies of animals laying around.
India has nine species of vultures in the wild. These are :
1. White backed vultures - Gyps bengalensis
2. Slender billed vultures - Gyps tenuirostris
3. Long billed vultures - Gyps indicus
4. Egyptian vultures - Neophron percnopterus
5. Red headed vultures - Sarcogyps calvus
6. Indian Griffon vulture - Gyps fulvus
7. Himalayan Griffon - Gyps himalayenisic
8. Cinereous Vultures - Aegypins monachus
9. Bearded vultures - Gypaotus barbatus or Lammergeier
The population of three species of like white backed vultures, slender billed vultures in the wild has been declined drastically over the past decade. The decline of gyps genus in India has been put at 97% by 2005.
This projects is confined to the district of Sundargarh with special reference to the city of Rourkela.
Field study was conducted on different dates and concerned authorities, persons and veterinary doctors were contacted to ascertain their views regarding the existence & extinction of vultures in Rourkela.
We have a telephonic conversation with Mrs. Binodini Devi, Municipality Councilor on dt. 10-08-07 on the topic of vultures and she expressed her inability to discuss on the topic as she has not seen vultures in and around Rourkela, since her coming to Rourkela.
On 10th August 2007, Dr. Manoranjan Dash Health Officer, Rourkela Municipality mentioned that the dead animals as and when found anywhere in the city immediately taken to a particular place and buried their. This is done to prevent decomposition of the dead bodies and consequent health hazards. Dr Das also said that vultures community are not seen for the last 30 years in Rourkela and he even jested with us.
On 9th Sept’07 we had discussed with Mr. Ajit Swain a resident of sector-16, steel township, Rourkela for the last three decades stated that he had seen vultures during the early 90’s in his locality – eating’s carcasses of animals. Now a days the vultures are not visible in his locality.
During our field study on 9th Sept’07 we had visited a very old khattal (Cow shed) of the steel township. Mr. Upendra, Mr. Sitaram, Mr. Madhusudan Yadav who migrated from Bihar to the steel city some 40 years back and during milk business started that, they were throwing the dead cows on the vast open field adjacent to their shed, which were eaten by large number of vultures available then till 90’s. The Yadav family stated that the vast open field is now being cultivated and has become paddy growing field. Hence they lack any such facilities of throwing dead cows. Moreover, such throwing of dead animals in the steel city has been prohibited. In addition to that Yadav’s family pointed out that the administering of some medicines to the cattle these days are responsible for killing the vultures.
We visited Dr Avijit Biswas, Veterinary doctor, Indira Gandhi Park, Zoo. He opined that as per his experience the extinction of vulture is mainly due to diclofence medicines given to the cattle and the carcasses of such cattle’s are consumed by the vultures, he stated that though Diclofenac medicine has been banned and instead Maloxican has been recommended as the alternative medicine, this ban has not been implemented in total.
To gather further knowledge and insight on the subject, Nandankakan Zoo was visited on 30th May ’07 and 1st June ’07. Nandankanan Zoo happens to be one of the captive breeding center for vulture in India. There Dr. P. Kar Senior Veterinary Officer, Nandankanan Zoo also mention the effect of Diclofence medicine is the major cause for the decline of vulture population.
Mr Arun Kumar Mishra, Administrative Officer of Nandankanan Zoo expressed happiness that Nandankanan Zoo has been selected as one of the six captive vulture breeding centre in India for protection of vultures.
The District forest officer of Sundergarh district Mr Murgasson stated that vultures are not seen either in the forest of Sundargarh or in the district for last 10 years.
Scientist, Veterinarians studying the carcasses of rapid decline of vulture population world over have not been able to find any single reasons for such a decline. However their analysis have thrown important lights on various causes responsible for the rapid decline. The some are analyzed below:
1. Use of Veterinary Drugs:
Diclofenac drug is a non-steroidal anti-inflammatory drug. This medicine was introduced in Indian Market in 1980’s. It is by far the most commonly available veterinary pain killer in India. Exposure of vultures to Diclofenac is presumed to occur to the consumption of carcasses of live stock that have been treated with Diclofenac can cause kidney failure and liver diseases. A study on experiment with some of the dead vultures of Diclofenac is their kidney.
2. General Environmental Condition:
Environmental contaminants have been seen known to cause heavy mortality in vultures and raptor populations. Pesticides and insecticides causes environmental contamination and death of vultures. There is wide spread use of chemicals / poison in water sources which is a potential source of contamination.
3. Deliberate Poisoning of Carnivores Leading to Secondary Poisoning of Vultures:
Deliberate or accidental poisoning have a significant impact on raptor populations, communal feeders such as vultures can be affected by such poisoning to obtain hides is a common phenomenon and may result in vultures being exposed to contaminated carcasses.
4. Low Food Availability:
Carcasses are the main food supplement to the vultures. The practice of dumping carcasses in the open was a predominant form of a disposal, now such practices has almost disappeared. Hence a gradual reduction of available food on the form of carcasses may be another cause of vulture population crash.
5. Exploitation and Persecution:
Vulture body parts in traditional medicine has led to exploitation, persecution of vulture for preparation of traditional medicine.
6. Transport, Infrastructure and Recreation:
Collision of vultures with flying air crafts were a serious prior to the significant decline of vultures population. Though the number of vultures dying due to such collision may be less, but to avoid air crash, shooting and poisoning of vultures near airfields have led impact on vulture population. The collisions of vultures with automobiles, trains, power lines is another factor contributing to the death of vultures. It has also been reported that vulture deaths have occurred during the kite flying festivals observed in different parts of India.
7. Infectious Diseases:
The postmortem findings of many vultures carcasses have shown death due to visceral gout. Visceral gout is an accumulation of uric acid within the tissue and on the surface of internal organs. Visceral gout is caused by renal failure, which is known to occur as a result of metabolic infections or toxic diseases. Sick vultures in India become increasingly weak over days or weak before death and are seen to head droop / neck drooping as they become further incapacitated. The presence of an infections disease or avian influenza virus is another major cause of large scale death of vultures.
8. Loss of Nesting Habitat:
The nesting habitats of vultures are affected by disturbances like cutting of trees, interference by the mankind and the natures furry. The large scale destruction of trees providing shelter to the vultures occurred during the 80’s prior to the awareness about the environmental impact. Super cyclones in Orissa, earth quakes and tsunami created havoc for the mankind and also vulture’s populations. So such natural phenomena also contribute to the rapid decline of vulture population.
The rapid decline and extinction of vulture population was first recorded at the Keolodeo Ghana National Park, Rajasthan during mid 1980’s to mid 1990’s followed by northern India road counts. This led to carry out survey at identified location throughout the country. This annual nation wide vulture survey were done to get an idea of the status of vulture population.
Data on vulture population changes across wider area of northern India in 1992-93 the repeat survey carried out during 2002-03. The survey pointed out 99.7% decline in Gyps bengalensis (white backed) during the period 1992-2003. Gyps indicns (long billed vulture) Gyps tenuirostris (slender billed vulture) declined to the extent of 97.4% during the period. That is estimated note of decline of Gyps bengalensis was 34% per year. The estimated rate of decline of Gyps indicus and gyps tenuirostries was 27% per year. The most recent census carried out in 2002-03 indicate a much rapid decline of 81% per gyps bengalenasis, 59% decline in Gyps indicus, and 47% decline in gyps tenuuirotris, the surveys provide evidence about the decline only in the three resident gyps species.
In India, the initial hypothesis for the drastic decline population were non –availability of food or an unknown viral epidemic disease. The former was clearly not the case. The investigation on hypothesis of epidemic disease were carried out by BNHS, IVRI and other institutions in association with researchers working aboard on the issue. Visceral gout, an accumulation of uric acid within tissues and on the surfaces of internal organs was observed in 85% of dead vulture found. Death was caused by renal failure, which is known to occur as a result of metabolic, infection or toxic disease.
Analysis of samples of the dead vultures during 2002-03 showed 21 cases of Avian gout while 17 samples did not exhibit Avain gout, Mircobiological studies that is Virus isolation, Electron Microscopy, Molecular biology, Bacteriology and Transmissibility all gave negative results.
Scientist / biologists have found a strong positive correlation between presence of diclofenac in the tissues of vulture and occurrence of visceral as gout. The concentration of diclofenac as low as 0.22 mg / gm of body weight was found to be lethal to vultures. The drug diclofenac was introduced in late 80’s as veterinary drug and widely available at a cheap rate across the country. This medicine considered to be very effective and hence has captured 5% and Rs. 20/- crores medicine of total veterinary market. This has led to wide spread and intensive use as medicine for the cattle’s. Hence it has been scientifically concluded that only 0.4% cattle carcasses need to have lethal level of diclofenac to cause the crash in vulture population witnessed in gyps species of vulture in India.
The drug extracted from tissues like kidney, liver and muscles of the vultures and examined at National Institute of Pharmaceutical Research and Training, Mohali, Hariyana, Department of Pharmacy, Birla Institutes of Technology Pillani have confirmed 72% of the vultures had detectable diclofenac in the tissues.
The cattle tissues were randomly collected for different parts of the country and extracts from the tissues have been analyzed at various laboratories mentioned above. It showed more than 10% of the cattle tissue samples had diclofenac residue.
Between 2002-04 it was observed that 72% of 15 white backed vultures and 13 long billed vultures from the wild has visceral gout, 14 gout and non gout cases were analyses for the presence of diclofenac. All the 14 gout cases have presence of Diclofenac. This led to the conclusion of perfect 100% correlation between gout caused by diclofenac. Out of 700 and tested sample collected from eastern, western, central and north India about 84 cases or 12% were found to contain some level of diclofenac. These findings sufficiently explained the causes of observed decline of vulture population. This also proved that very low rate of carcasses contamination can drive to massive decline of vultures. Survey results indicate that diclofenac prevalence in western India is more than 5% in cattle carcasses. This is sufficient to observe declines
The importance of vultures in protecting our biodiversity is well known to the mankind. Vultures are scavenging bird they clean the environment by removing the carcasses. This nature of job voluntarily performed by the vultures since ages has helped in reducing epidemics like rabies and anthrax.
Vultures are given highest priority by the Parsi community as they dispose of the tower of silence. Hence vultures are vital necessity and part of religious requirement for the Parsi religion.
The decline of vulture population has posed a greatest threat to the Parsi community.
The sudden disappearance of vultures during the last two decades has been a cause of concern to the environmentalists. New awareness has been created to study the reasons of decline and protect the scavenging birds, the government, NGO’s and private institution have come together to spread awareness on the role played by the vulture in protecting ecosystem and the mankind since ages.
The scientist and environmentalists have so far found out certain reasons for the decline in vulture population like use of diclofenac, poisonous medicine, loss of nesting habits etc. Which is man made causes of decline. Hence awareness has been created to know and remove the man made causes to stop further decline in vulture population.
In addition to the above, certain proactive actions like establishing vulture breeding and care center have been taken up to increase the vulture population.
Further research needs to be encouraged and financial support given to organizations. Engaged in protecting, preserving and increasing the vulture population. These actions will go long way in protecting our biodiversity and mankind from the decline of vulture population.
Vultures perform important functions in our ecosystem. They provide service to mankind from potential health risks posed by decomposing live stock carcasses. So it is the responsibility of all concern to protect and prevent the disappearances of vultures in India.
To preserve and protest these endangered species by taking the following actions.>
Ban Diclofenac Use Meloxicam Drug
It is essential to recognize the impact of diclofenac on the decline of vulture population. The pharmaceuticals industry should be made aware of the adverse effect of these medicine on vultures. This medicine should be completely stopped from being manufactured as a veterinary medicine. In its place Meloxicans drug would help. Conservation of vultures
Awareness and Educational Campaign
Rural and village based veterinary doctors be made aware through campaigns, regarding the impact of Diclofenac an vulture population. This campaign should reach out to the grass root level. Non-Government organization (NGO’s) to be involved in such campaign.
Establishment of Captive Vulture Care / Breeding Center
A network of captive vulture care and management center to be established in different zones in India, to maintain a healthy population of vultures. This will prevent all vultures being affected by diclofenac or other reasons for their decline.
Captive vulture breeding centers should be established in different region of the country for vulture care and their population increase.
Vulture breeding and conservation center established at Pinjore, Hariyana in 2001 Buxa in West Bengal in 2005, Four more centers, Nandankakan in Orissa, Bhopal in Madhya Pardesh, Hyderabad in Andhra Pardesh, Junagarh has been established in 2006-07, These ex-sites conservation center worked for captive breeding followed by re-introduction in wild.
Analysis of Sick Vulture Specimen
Recognized institution to be established to collect and send the sick vultures to their laboratory or other laboratory for analysis and identification of the factors and sickness of the mortality.
Monitoring of Vulture Population
It is essential to establish agencies to continue survey and monitor in different regions to study the vulture population decline and their recovery.
It is necessary to identify the potential and strong hold vulture population in each state in India. To develop a plan to protect and manage the vulture. The protection and management should include awareness drive not to use diclofenac in the live stock sector.
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