Longevity & Causes of Death

Elephants

Longevity & Causes of Death

Longevity

  1. The average lifespan of elephants is about 65 years of age or more.
  2. An elephant calf's first year of life is its most vulnerable time with mortality rates exceeding 30%.

Predators

  1. Carnivores (meat eaters) such as lions, hyenas, and crocodiles may prey upon young, sick, orphaned, or injured elephants. Humans are the greatest threat to all elephant populations.

Disease

  1. Anthrax is one of the most fatal diseases impacting elephants. Anthrax is a bacterium that causes high fever, shivering, ulcers, and swellings. This disease may be spread through contaminated water or soil.
  2. There are a host of illnesses that are specific to elephants, such as trunk paralysis and elephant pox.
  3. Elephants are susceptible to some diseases spread by mosquitoes and to some inflictions that affect humans, such as intestinal colic, nettle rash, pneumonia, constipation, and even the common cold.
  4. Tuberculosis is a disease caused by bacterium that affects the lungs. It is through tiny droplets in the air and can infect humans and elephants. It is characterized by chronic weight loss, nasal discharge, coughing, and diminished appetite.
  5. When ill, elephants help themselves in a variety of ways. Digestive diseases may be treated through fasting or through natural treatments such as consuming bitter herbs, bark, or alkaline (basic) earth. Wounds may be protected from insect or worm infestation by coating them with mud.

Human Impact

  1. The main threats to elephant populations today are habitat loss/ fragmentation and poaching.
  2. Elephants may require a few hundred to a few thousand square kilometers of habitat as a home range. With increased human settlement, elephant migration routes have been greatly obstructed.
  3. African elephant populations are threatened by poaching for ivory and habitat loss/fragmentation. Due to the overall smaller tusk size in Asian elephants, poaching is not a primary concern to their conservation.
  4. Poaching for Ivory
    • Elephants have long been hunted for the ivory in their tusks. Some African tribes have utilized the water-absorbing properties of ivory as rain predictors. However, the greatest use of ivory is for the carving and creation of billiard balls, piano keys, bagpipes, buttons, and ornamental items. In 1988, the going price for ivory was between $200US and $300US per kg ($100US to $150US per lb.).
    • Currently it is illegal to poach elephants. As long as there is a demand for ivory, however, poaching will continue. Today, an estimated about 70,000 African elephants are killed annually for the ivory trade. Some of this ivory comes from legal sources, such as culling (legalized killing), but about 80% is derived from poached tusks.

      Poaching has led to the indiscriminate shooting of elephants of all ages, resulting in a decrease in the average tusk size of surviving elephants' offspring. The average tusk weight for an African elephant in 1982 was 9.7 kg (21 lb.). The average tusk weight in 1988 was 5.9 kg (13 lb.). In 1990 the average weight was reportedly 3 kg (6.6 lb.). In 2004 the average weight was reportedly 3.6 kg (8 lb.).

      The primary ivory-importing nations are Japan, Hong Kong, the United States and several European countries.

      Unfortunately, the elephants' home may also provide retreats for armed opposition groups during times of war and political unrest. This adversely affects elephant and other animal populations by reducing the number of areas they may safely inhabit. Funding for some civil wars is partially obtained from the sale of poached ivory.


    • Poaching Repercussions

    • Survival is a great challenge for orphaned young due to the sociological importance of maternal upbringing. The lack of guidance, leadership, and experience make orphaned young more susceptible to predators, injuries, and diseases.
    • Abnormal behaviors may develop in orphaned young bulls that have not benefited from proper maternal care. Documented behaviors include abnormal aggressiveness, including fatal attacks, and reproductive inexperience.
  5. Habitat Loss
    • Elephant ranges throughout Africa and Asia are increasingly coming into contact with human settlements, leading to the Human-Elephant Conflict (HEC). Each year HEC poses a grave threat to both humans and elephants.
    • Rapid human population growth and development has fragmented many elephant habitats; thereby compressing populations into a smaller areas. Due to the large dietary requirements of elephants, the fragmented habitats may become over-exploited and damaged.
    • Habitat fragmentation reduces breeding opportunity thus decreasing populations and limiting genetic variability.


    • Crop Damage

    • As the human and elephant populations grow closer together in proximity, there are increased occurrences of crop raiding by elephants. Crops provide a dense amount of food in one area and are convenient for elephants. An elephant herd can satisfy all of its dietary requirements for 24 hours by spending just seven or eight hours in a cultivated field.

    An adult male Asian elephant entering a village in Nepal
    foraging for food.

    • Many field owners can lose an entire year's crop in just one night of these raids in addition to risking starvation for themselves and their families. A herd of 20 elephants can eat and trample down two hectares (five acres) of crops in a single night. Commercial agricultural crops, such as oil palm and rubber, can net millions of dollars in losses annually.


    • Woodland Destruction

    • There has been significant debate in regards to woodland destruction by elephants. Elephants debark and push over trees for feeding and strength trials. Damaged trees may be susceptible to wood-boring insects and fungi, as well as wind and brushfire damage. There is no consensus as to whether elephant feeding is the sole cause of woodland damage. Other factors such as a rising water table, causing increased soil salinity may result in difficulty for tree roots to absorb water. Additionally, there is evidence that fire caused by drought significantly alters trees' propagation. Therefore the challenge of tree regeneration may not be directly attributed to elephant feeding habits. There is argument not only about what causes woodland damage, but how to solve it and whether or not it is a part of natural elephant vegetation cycles.


      Contaminated Water Sources

    • Due to the increasing number of elephant populations in increasingly smaller areas, many elephant populations share limited resources. Overcrowding can lead to contamination of water resources and increased occurrences of parasitic diseases.


    Culling

    • Culling is the legalized killing of an animal and is a controversial and debated topic. Due to habitat fragmentation, there are increased numbers of elephants in smaller spaces of land; thereby contributing to over-exploitation of natural resources in the area. Elephant culling has been used in areas where there are too many elephants for the habitat to support. Comparisons have been drawn between culling and legal hunting measures that are taken to manage deer overpopulation.
      • Deer, like many animals, if they overpopulate have to go further to search for food. These searches often lead them into cities and highways, which may increase human-conflicts and/or getting injured by vehicles. Legal hunting is a preventative measure that averts deer from becoming overpopulated and reduces instances of starvation and injuries.
    • Overall, African elephant populations are classified as threatened. The justification for culling is generally that the number of individuals has surpassed the habitat's carrying capacity (the amount of available resources that a habitat has to sustain life). Culling is not an indication of the overall conservation status of a species.
    • Entire populations are generally culled within minutes, in order to reduce distress on other herds in the area, prevent abandoned offspring, and minimize trauma. Refer to poaching repercussions.
      Refer to poaching repercussions.
  6. Large Game Trophy Hunts
    • Long revered for strength and size, elephants have been sought after for large game trophy hunts. Affluent individuals, primarily of American and European origin, spend between $15,000 and $20,000 to hunt an elephant.
    • A game warden usually supervises the hunting expedition and a technician accompanies them to prepare legal trophies, usually from the tusks and feet. Meat is distributed amongst local people in the area.
    • In some African regions, large game trophy hunts may generate more income from mediocre (average to below average) lands than from conventional agriculture due to the challenging environment for crop growth.