Using Behavior to Deter Elephants from Crop Raiding

Standing next to an adult elephant is incredibly intimidating; adult male African elephants can weigh more than 15,000 pounds. Many farmers fear and hate them because cropraiding elephants can destroy entire fields and even threaten farmers’ lives. Imagine an angry farmer going up against a hungry 6-ton elephant! In southern India, during a three-year period 60,939 incidents of cropraiding occurred and 91 people were killed [1]. This also presents a problem for the conservation of elephants because retaliatory killing of elephants often occur and public support of elephants is incredibly important for their survival.

There have been many methods tested to deter elephants from raiding crops, however, elephants are often too big and smart for these deterrents to work: elephants will push over fences or simply go around them [2], culling problem animals just makes way for new crop raiders, and the electrical fences set up by the government will either be destroyed by the elephants or fall into disrepair because of a lack of upkeep [3].

Some new and upcoming methods to deter crop raiders include using elephant behavior to keep them away from cultivated land. It may be humorous to think about the largest land mammal running in fear of a simple bee, but because of the thin skin around elephants’ eyes, trunk, and under their legs, they are actually susceptible to bee stings just as we are. A swarm of bees has been known to send entire herds into flight [4]. Setting up bee hives along well known paths and near key habitat areas, such as water sources near crops, has been proven to deter elephants from those areas, however, often times the elephants will go around them to get to where they want to go: the water hole, or the tasty crops [4]. Although “beehive fences” won’t completely work to deter an elephant from a whole crop, they can be used along well-established paths either to guide them away from a crop or keep them from coming near water sources near crops.

While humans rely mostly on eyesight, the elephant’s most powerful sensor is their nose. Just like a human could be blinded by a bright light, elephants are “blinded” by extremely strong scents, which is why another promising elephant deterrent is the creation of rope fences covered in chili grease. Chili grease fences are created with a mixture of chili essence, motor grease, and sometimes tobacco [2]. One farm encircled by a chili rope went un-raided for two years despite nine attempts [2]. If there is a way around the fence, the elephant will find it. However, when faced with the decision to either go near the fence and get to the crops or leave, all elephants chose to avoid the fence and the crops were protected [2]. The downside to this method is the constant upkeep of the rope: the paste must be reapplied at least once a week, more during the rainy season.

These methods of deterrence that utilize animal behavior are extremely promising because they are specialized for specific behaviors and are non-lethal to endangered animals such as the elephant. Decreasing crop raiding through effective methods that do not harm the animal is one way of improving conservation efforts for elephants. Villages with agricultural practices are much more likely to support conservation efforts when their livelihood and lives aren’t being threatened by neighboring elephants.

 

-Mackenzie Platt

Citations

  1. Gerhardt, K.V., Niekerk, A.V., Kid, M., Samways, M., and Hanks, J. (2014). The Role of Elephants Loxodonta africana Pathways as a Spatial Variable in Crop-Raiding Locations. Orynx 48(3): 436-444.
  2. Sitati, N., and Walpole, M. (2006). Assessing Farm-Based Measures for Mitigating Human-Elephant Conflict in Transmara District, Kenya. Oryx 40(3):279-286.
  3. Moss, C.J., Croze, H., and Lee, P.C. (2011). The Amboseli Elephants: a Long Term Perspective on a Long-Term Mammal. University of Chicago Press, Chicago.
  4. 4.Vollrath, F., and Douglas-Hamilton, I. (2002). African Bes to Control African Elephants. Naturwissenschaften 86(11):508-511.

24 thoughts on “Using Behavior to Deter Elephants from Crop Raiding

  1. mberne

    I never knew that elephants were scared of bees or that their primary sense is smell. I thought this was very interesting and unique in that I have never heard of a “bee” or “chili” fence! What a creative and humane way to keep such a large (and endangered) animal out of a particular area.
    What crops do elephants prefer? Are there any crops that they dislike that can be planted alongside preferred crops to keep them from wanting to invade them at all?

    1. Mackenzie Platt

      Using strips of unpalatable crops around the more palatable crops is another solution farmers have used to deter crop raiding elephants. In the South Western Ghats mountain range in India, the East side of the mountain range grows more annual crops (Cereals such as paddy, maize, and finger millet) and has a higher rate of human-elephant conflict than on the Western side which cultivates more perennial crops.

      Baskaran, N., Kannan, G., Anbarasan, U., Thapa, A., and Raman, S. (2013). A Landscape-level assessment of Asian elephant habitat, its population and elephant-human conflict in the Anamalai Hill Ranges of Southern Western Ghats, India. Mammalian Biology 78(6):470-481.

  2. kburrus

    I like the idea of a more natural deterrent of elephants from raiding crops. it reminds me of a technique used for wolves by streaming red flags around the area of interest. These have been said to also work to keep wolves away from a heard of sheep. I think that keeping up the chile rope would be a lot easier than a giant expensive eclectic fence that might also keep out other animals. This would be bad for the connectivity of other species. I would be interested in seeing this technique done more and seeing if it would be a good long term answer and also looking at why after 2 years it didn’t work on the elephants.

    1. Mackenzie Platt

      Electric fences are cited as the best deterrent for crop raiding elephants, but as you said they are hard to upkeep. When put up by the government they are often not taken care of well enough, fall into disrepair and then are useless. Also there have been cases where elephants knock over trees onto the fence and cut off the electricity. Electric fences are also expensive and small, subsistence farmers cannot afford them. However when they are kept up they are extremely useful in keeping out most elephants.

  3. ematth

    I also had never heard of the “bee” fence or the “chili” fence! I think these sound like great ideas because they are neither harmful to the humans or the elephants (other than a couple of bee stings and some spicy nasal passages). These also sound economically friendly because they seem to work, and are much cheaper than other more invasive methods. This makes me wonder why we don’t hear more about these “natural” fences, as they seem much easier. Farmers and gardeners have numerous cheap and natural methods for warding off weeds and pests, they should apply this mindset to larger cases of endangered species, such as the elephants.

    1. Mackenzie Platt

      I enjoy that there are more and more creative, behaviorally based methods of deterrents coming into play. I wish keeping out elephants from crops was as easy as warding off weeds however elephants seem to find ways around every deterrent because they are so smart and stubborn!

  4. leorah

    These are great concepts and a great post! I like that you distinguished the bee fences as guiding behavior, not necessarily 100% preventative. I think of these things were used in combination it could be really effective, although the chili fences do sound really high-maintenance.
    As for the bees, do farmers have to plant additional flowering crops to sustain the bees throughout the year, in order for it to be effective? Or is that not an issue in these regions?

    1. Mackenzie Platt

      The bees would need a certain amount of flowering plants to be able to sustain their hives. There are definitely other factors to these methods that have yet to be considered. Unless the habitat is good enough for the bees they will not stay in the hives and this method would be useless.

  5. reneev

    I like that you mentioned several possible solutions and explained why they might work! I thought the chili fences were particularly interesting because it seems like such a simple idea, but it apparently works pretty well! I think it’s great that there’s several non-lethal options to keep elephants from interfering with humans, especially since it seems like most people just want to get rid of the elephants that engage in this behavior.

    1. Mackenzie Platt

      From a zoology viewpoint I wish humans and elephants could get along better, however I also see the viewpoint of the farmers who depend entirely for food and money on these crops that can be completely destroyed in a single night by one hungry elephant. Non-lethal deterrents can hopefully begin mending this relationship and allow for better conservation efforts to save the elephants.

  6. amajor

    Hmm, I too have never thought that an elephant was so scared of bee (at least it’s a better and reasonable fear than the stereotypical idea of elephants being afraid of mice), but understanding Africanized killer bees, it makes sense that they would be scared to death of them. I love that you’ve described that not only can the “bee fence” prevent elephants from getting into crops, but can also safely guide them away from cultivated lands. I also find it grand and interesting to mention the chili fences as well, interesting usage of the elephant’s senses in a cheap way. But I will say this, while you get great on showing the downsides of the chili fences, you didn’t mentioned the downside of the beeline fences (such as you need a large supply of flowers or nectar-like substance to sustain those hives and so on) and how that can be showed (You could either always raised flowering crops or that while you can have real bee hives, you can also add on mechanical “false beehives” that give out the illusion of them being real beehives, always making buzzing sounds and vibrating on physical contact). But other than that, I would have to say that this is a grand deal you presented, a grand deal indeed.

    1. Mackenzie Platt

      There are downsides as you mentioned to the beehive fences as well as the chili pepper ropes. The reason that the beehive fences work however is the negative reinforcement of the bee stings. Using fake beehives only work on elephants the first time and when they learn there is no bees they completely ignore the fake hives. Using fake hives would be a much simpler and economic solution however elephants are quick learners and too smart for their own good!

  7. Lisa Angeloni

    It seems some of the most creative solutions to human-wildlife conflict have been developed for deterring elephants. I had also heard of noise and light alarms, but I believe elephants tend to habituation to those fairly quickly. One interesting possibility with the beehives is that they could provide economic incentives as well, if farmers can make money from selling the honey they produce. Save the Elephants has started promoting “Elephant-Friendly Honey” with this in mind (http://savetheelephants.org/human-elephant-conflict/elephants-bees).

    1. mplatt Post author

      I agree with you that a big incentive for using bee-hive fences is the economic possibility of selling the honey! I do know one paper mentioned however that it can be dangerous for the humans because if African killer bees, which have the biggest impact on elephants, are used than the humans have a large chance of getting injured as well.

  8. Lacey Humphreys

    I love the idea of the bee hive and chili paste fences. A very unique and affordable way to solve a very real problem. For the bee fences, what kind of fauna do you have to have around in order to sustain a large population? Also, would the planting of these flowers in order to sustain the bees cause more fragmentation to the land?

    1. mplatt Post author

      I would have to do more research into the specific type of flowers that certain species of bees in Africa use however this should not cause fragmentation as elephants will be able to walk right through this fauna

  9. Amy D'Arcey

    The chili fences cracks me up, what a great idea! Along the same vein as Austin’s thoughts, what if you could simulate the presence of bees? You could find out how they detect the bees, if it’s sound or vibration and mimic that with a recording or something. Since the methods being used now don’t seem to work that well it’s urgent for the elephants’ and the farmers’ sakes to find something that does and these are some creative ideas.

    1. mplatt Post author

      If only it were that easy, however elephants are so smart and stubborn that after their first encounter with the “fake” hives they learn there are no bees and promptly ignore them. There has to be the presence of the negative reenforcement (aka the stings of the bees) to keep them away.

  10. sberg

    That’s pretty funny that they don’t like bees like most humans! They are just so big and a tiny bees and their sting scares them. The chili fence is really good idea because the chili is a very stingy scent that could really make your nostrils run if you get to close. I love your ideas really cool!

    1. mplatt Post author

      Thanks! I hope researchers can use these behavioral methods and perfect them to really help conserve the elephants and decrease human-elephant conflict!

  11. ssteele1

    These are some amazing solutions to the crop-raiding problem, but I wonder why these aren’t already being implemented. Behavior is one of my main interests and I think it should be more carefully considered when dealing with these kinds of problems. These are really great ideas, are they expensive to maintain? The olfactory solution seems really promising, but does the smell have a time limitation and need constant re-application?

    1. mplatt Post author

      The chili pepper paste must be reapplied often, especially in the rainy season which is a lot of upkeep. Both ideas are being used in some places however they don’t work for every place it depends on many factors.

  12. mplatt Post author

    No solution is perfect unfortunately and neither of these solutions have a perfect success rate at keeping elephants out of cropland. Bee hive fences require bees which require flowers and the chili pepper rope does require constant upkeep, especially in the rainy season when the paste washes off quicker. I agree with you that issues such as these should be carefully considered and the behavior of the animal should be factored in when coming up with solutions.

  13. Savimay

    I think you have some amazing ideas here. It makes sense to use what we know about elephant behavior to prevent crop raiding. I was wondering if perhaps farmers could plant crops that elephants are not interested in but would still provide an income where they could purchase food elsewhere. For instance if the elephants hate chilli, farmers could maybe grow chilli crops to sell and the elephants would naturally avoid the area. Or maybe even buffering the area with chilli crops around the food crops in the center. Just some food for thought, great article Mackenzie!

Comments are closed.