- The Ministry of Environment, Forests and Climate Change has allocated funds to the Wildlife Institute of India, to implement a pilot project on contraception for four species of wildlife.
- There are many factors to be considered even at the pilot stage to make the project effective.
- While experts advise proceeding with caution, there are critics who do not even want the country to try out the contraception project.
Amidst rising human-wildlife conflicts in the country, India plans to roll out a pilot experimental research project in the Himalayan state of Uttarakhand to test the most appropriate method to control populations of four species of wild animals – blue bulls or nilgai, elephants, monkeys and wild boars – whose growing numbers are causing extensive crop damage.
The Dehradun-based Wildlife Institute of India (WII) will take the lead, under a Rs 105 million ($1.63 million) project of the Ministry of Environment, Forest & Climate Change (MoEFCC), of which Rs 65 million ($1.1 million) have already been allocated in India’s latest 2018-19 budget announced by Finance Minister Arun Jaitley on February 1. “This is the first time the MoEFCC will undertake a research project on animal reproductive control,” said WII director Vinod Mathur.
Surgical sterilisation or contraceptives, both methods will pose a range of problems for Indian wildlife scientists to grapple with. “These include problems of capturing the animals, choosing the appropriate method, scaling-up for use in large populations; cost of the scale-up; and availability of surgical equipment or contraceptives in sufficient quantities,” added Mathur.
For one, WII, whose scientists are more used to conducting animal studies in the wild, will now have to construct in-house facilities for the captured animals, where they can be sterilised or given the pill, and given post-surgical care, before they are released into the wild again.
The thinking on contraceptives for animals was triggered partially because of the increase in the numbers of some animals, which is also resulting in more human-wildlife conflicts.
India is a mega-diverse country, occupying only 2.4 percent of the world’s land area but harbouring 8 percent of the world’s recorded species, including 91,000 animal species and 45,000 plant species and 17 percent of the world’s people. It is home to four of the global biodiversity hotspots, and has more than 100 national parks, more than 500 wildlife sanctuaries, and an extensive network of protected areas and wildlife reserves.
The country’s growing population, expanding agriculture, increase in the number of grazing livestock, and focus on development projects are putting fragmentation pressures on natural habitats and also increasing the incidence of conflicts between wildlife and humans. Flagship conservation programmes such as those for elephants and tigers are struggling to contain these conflicts and minimise damage to both humans and wildlife.
Need careful planning and monitoring
Wildlife experts say that while the country does need to make a beginning by testing the concept of contraceptives, any such long-term, large-scale project will require not only money, but also logistical support and careful planning.
“It is feasible to control animal populations using contraceptives, usually vaccines,” said Raman Sukumar, professor at the Divecha Centre for Climate Change, Centre for Ecological Sciences, Indian Institute of Science, Bangalore. “There are several examples where populations of animals such as African elephants and wild (feral) horses were controlled. And although there is more than one approach to contraception in wild animals, the most favoured method involves injecting a vaccine (immunocontraceptive) in females that prevents the egg from being fertilised.”
N. V. K. Ashraf, scientist at the Wildlife Trust of India, based in NOIDA near New Delhi, said that there are various options including the administration of steroids that prevent estrous cycle in females, anti-sperm vaccinations, immuno-contraceptives that prevent ovulation and chemicals that cause permanent sterility, although the last one is the least likely method to be employed in free-ranging wildlife. “No single method or drug of choice would be applicable for different wildlife species and even within species for different management situations,” he commented.
According to Ashraf, there are also several mechanisms of delivery of drugs and their mechanisms of action. The challenge lies in administering the drug. “Injectable contraceptives will give immediate results, but injecting every animal using a remote-delivery mechanism would be cumbersome. Any attempt to dart one animal in a herd would increase their flight distance during subsequent attempts, for example, in nilgais.
Meanwhile, oral contraceptives have their own disadvantages, he says. “There is no guarantee that all animals will consume the desired dose, and no guarantee that the animals would take medicated baits, especially in the case of monkeys.”
Many researchers abroad have also been addressing the issue of impacts on animal health, said Sukumar. The key is obviously to find a safe method of contraception. The effect of immunocontraceptives is reversible.
Talking about population dynamics, Sukumar said that the idea is to slow down population growth in order to achieve a stable population (or even a declining population to a desired level). However, so far in India there are no examples of successful use of such methods.
“All drugs have side effects and the challenge lies in using one that causes the least impact on the animal,” said Ashraf. “Studies have shown that they can affect body condition, reproductive hierarchy, and social behaviour because they are used among social animals largely. And oral contraceptives can end up affecting non-target species.”
A multi-disciplinary approach is needed
The development and successful execution of any project to contain animal populations through contraceptives would be expensive, especially if it is to be used on a large scale, said Sukumar. “More importantly, there are several logistical issues to be resolved. For instance, if you are applying this on a large elephant population, an individual female elephant has to be repeatedly vaccinated (remotely through a dart gun) every few years. This means that an identification profile has to be built for each elephant population which is quite a task.”
Such projects are complex and will require the participation of experts from several fields (and institutions) – reproductive biologists, veterinarians, ecologists, population modellers, animal behaviourists, he pointed out. The idea should be to develop working models that should be tested under captive conditions and later taken to the field for implementation in small wildlife populations.
Also, dedicated research and vaccine delivery teams will have to work in coordination. Therefore, the use of such contraceptives is most likely to succeed in smaller populations or animals in captivity.
“If the idea is to control a wildlife population to reduce wildlife-human conflicts, one should not expect immediate results,” cautions Sukumar. “Birth control will only slow down the rate of population growth, but long lived animals such as elephants would continue to be around for many years”.
Ashraf agrees that while it is possible to control animal populations with contraceptives, and there has been few, but limited, success stories abroad, especially in deer; several factors influence the success of any such measure. “The success will be evident if (the measure is) implemented in confine or restricted populations, and not in populations that have a contiguous distribution range,” he added.
“There is a perception that there is an “overpopulation” of certain wild species,” observed Neha Sinha, a wildlife conservationist based in Delhi. “There have been no standardized population estimations of such species which are considered nuisance animals, such as wild boar, nilgai and Rhesus macaque.”
Sinha welcomes any scientific design for contraceptives. Experts tend to suggest using drugs whose changes can be reversed. “There should be monitoring and evaluation at every stage to ascertain how the population structure changes after contraceptives are administered, and if it achieves project goals.”
Also, she says, “it is also important to study the drivers of foraging and movement ecology of target animals —are they locally abundant only because they are being driven off from other areas? What is the locally available food and resource distribution?” Several species can be locally abundant but otherwise threatened.
Some animal activists are not enamoured with the idea of contraceptives to control wildlife population. Environmental & Animal Research Society (EARS), an NGO based in Chandrapur in Maharashtra state, has launched an online petition against the proposal.
Human-wildlife conflict is a problem created by humans and not by wild animals, the petition argues. It is humans who have reduced the forest cover through developmental activities, which destroys the animals’ natural habitats and increases their movement near human settlements.
Even if the pilot project is initiated soon, it will take time to yield tangible results. “Do not expect results overnight. It will take three to five years before the results of the pilot project will be out,” cautioned Mathur.
The wildlife contraception project is likely to be a slow gestation one.