Farmer's world over faces the attack of vertebrate pests on their crops in the field. Major vertebrate pests are the rodents, birds, wild boar, monkeys, bats, elephants, and nilgai. They pose an increasing threat to standing crops and stored commodities. The man-animal conflict began after disturbing the wide forest area for agriculture. The natural environment for wild animals was destructed and hence animals began to survey the villages for food.
In India, there are more than 100 rodent species are present that includes porcupines, squirrels, gerbils, bandicoots, rats, mice, and voles. We focused mainly on controlling the rodents and many types of research happened in this count. But, the damage made by other vertebrates like wild boars, nilgai and monkeys are not properly addressed. Recently, about 200 acres of sugarcane crop was destroyed by the wild boars along the Minjira river near Singur dam in Telangana. Similarly, monkeys of different species have become a major crop destroyer in fruit growing areas of J&K and Himachal Pradesh.
The major crop raiding monkeys include Rhesus macaque, Bonnet macaque, Assamese macaque, and Hanuman langur. Studies revealed that the main reason for monkeys encroaching beyond the boundaries is loss of species-specific habitats, habitat degradation and fragmentation, intensive agricultural practices , insufficient prey base and food material, increase in human and livestock population, competitive exclusion of wild herbivores, land use transformation, developmental activities, growing interest in ecotourism and increasing access to natural reserves.
In fact, the animals lost its basic requirements of space, shelter, and food and thus the conflict began. As forest is cleared for agricultural expansion, human and wildlife habitats are overlapping. The strict demarcation between agricultural land and forest is needed and creation of rich environment inside man-animal forest for the animals are to be made to stop the menace in future.
Rhesus Macaques
The Rhesus monkey is one of the famous species of Old World monkeys and distributed in large population across the country. It is native to Asia and has a widest geographical range in India. It lives in a wide range of habitats, from flatlands to high elevations up to 3000 meters in the Himalayas and will survive extreme heat and cold climates above 45 degrees and below zero respectively. Rhesus monkeys, generally, live as big groups comprising 20-200 individuals that include males, females and children. The average male-female ratio will be 1: 4. Rhesus are mostly herbivorous , feeding on main fruit, seeds, roots, buds, barks, leaves, flowers and cereals, but occasionally eat termites, grasshoppers, ants, beetles, bird eggs and cooked food. When food is abundant, they save it in specialized pouch like cheeks.
They are very aggressive in nature and are able to adapt to the varying environments and live very comfortably among human habitation. They are the top most primates in India, which damage maximum agricultural crops than other species.
Bonnet macaque
Bonnet macaque is endemic to South India with habitats including evergreen high forest and dry deciduous forest of Western Ghats and some of Eastern Ghats. They also live as groups with an average troop size of about 30 individuals. They feed on fruits, nuts, seeds, flowers, cereals and invertebrates. Bonnet prefer to live in human dominated landscapes especially agricultural landscapes which are along the road sides. The man-monkey conflict is high in their locations and hence, its numbers declined drastically in recent years and the remaining members are forced to shift from roadside to interiors.
Hanuman langur/ Gray langur
There are 6 species of gray langur found in India. Black footed and tufted gray langur mostly found in forest of South India. The other species like Kashmir Gray langur, Tarai gray langur, Northern plains gray langur, Southern plains gray langur occupy the northern part of the country. Hanuman langurs are bigger in size and are folivorous in nature. They crop ride when their habitat was destroyed for agricultural activities, permanent settlement, fuel and fodder use and for procuring forest produce.
Constraints in Management
Management of problematic species mainly depends on their status as per the Indian Wildlife Protection Act (IWPA)1972 and International Union for Conservation Nature(IUCN). Many of the problematic monkey species belong to endangered, vulnerable and near threatened in IUCN and Schedule I,II and III of IWPA. A common management technique will not succeed as each location and species presents a particular scenario with different factors affecting the intensity and occurrence of crop raiding. The strategy generally adopted is not to eradicate the menace ,but to limit and control as agreeable with the rules pertain to it.
Existing management methods
1. Guarding/ chasing
Guarding field in person or employing a wage will certainly helps in driving away the monkeys from the field, but it is expensive and keep people away from other activities.
2. Noise/bells
Beating the drums/ plates will make the animal away from cropped areas, but have to be vigil on their movemen
3. Stones/ slingshots/spears
Throwing stones by using a slingshot or locally made ‘gophan’ are useful in chasing the monkeys, but causes considerable damage to the animals.
4. Rice balls
Keeping the rice balls having boiled rice, crushed ground nut seeds, red chili and coconut oil around the field deter the monkeys. As soon as they taste the mixture, they feel burning tongue and thirstiness and will avoid the area.
5. Dry fish
Tying of dry fishes to the branches of , around the fields and above the crop will help in keeping away the monkeys because of the irritating smell emanates from the dry fish.
6. Dogs/ langurs
Monkeys fear about and avoid unfamiliar species like dogs and langurs and hence this method is very effective.
7. Painting individuals
Farmers capture a dominant male among the monkeys, paint him white and red and rerelease him. When he runs towards the monkey troop, they scare and run away
8. Translocation
It is effective in rare cases, but the shifting of all animals from one location to other is risky and needs permission from different agencies.
9. Sterilization/ birth control
It is also a risky activity and capturing all males for sterilization couldn’t be possible.
10. Cropping patterns
Altering crops may be a viable solution. thorny brinjal or ginger which are unattractive to monkeys may force them to shift the location of stay for better food they like. Later, the farmer can alter the crop pattern to better products.
11. Buffer zones
Regions of partially cleared land surrounding farms or buffers of less desirable crops can be made as an option
12. Conservation of forest
Conservation of forest for the wild animals is the best option . The suitable forest habitat will lessen the visit of monkeys to the farms.
The traditional ways likes guarding and throwing stones and keeping dogs and langurs at the fields and many methods explained above were effective to some extent, but due to the intelligence and higher steadiness, the management strategies that have not helped in managing the monkey menace in agricultural crops. There is a need to develop the suitable cost effective management strategies to reduce the damage by crop raiding monkeys. The future research using technologies may ponder a creative and long lasting solution to the crop raids by the monkeys.