Loxodonta africanaAfrican bush elephant

Geographic Range

The range of African elephants (Loxodonta africana) is patchily distributed across central and southern Africa in the Ethiopian Region. Remnant populations exist as far northwest as Guinea-Bissau and as far northeast as Ethiopia. Disjunct populations exist southward into northern South Africa, and include contiguous populations in Gabon, Tanzania, Botswana, and Zambia. Once present in Burundi, Gambia, and Mauritania, they've now been extirpated from those countries. These elephants were extirpated from Swaziland, as well, but have been re-introduced here in recent years. (Blanc, 2008; Laursen and Bekoff, 1978; Thomas, et al., 2008)

Habitat

African elephants are found in many habitats of Africa such as savannas, rain forests, woodlands, scrub forests, occasionally deserts, and beaches. However, due to poaching threats protected sanctuaries are their main habitats. Within these sanctuaries, these elephants will inhabit areas that have sources of water and abundant vegetation for foraging. Across these habitats, the elevation level ranges from sea level (0 meters) to 4000 meters. (Duffy, et al., 2011; Harris, et al., 2008; Laursen and Bekoff, 1978; Mashintonio, et al., 2014)

  • Range elevation
    0 to 4000 m
    0.00 to 13123.36 ft

Physical Description

Currently, African elephants are the largest terrestrial organism. Female elephants can range from 2,000 to 3,500kg in mass and stand 2.2 to 2.6m at shoulder height. Male elephants are larger, ranging from 4,500 to 6,100kg in mass and standing 3.2 to 4m at shoulder height. Distinguishing characteristics between the sexes include head shape, width of forehead, saddle-back vs straight back, and tusk size. Males are broader with a curvy build. Both sexes have two thick, ivory tusks which are curved and can reach up to 350 cm in length. African elephants have muscular trunks that are able to grab objects and can be used for breathing purposes. They can grab objects due to the unique shape at the end of the trunk. Their sizable ears are triangular and can help keep them cool in the hot, summer months.

African elephants have creased, gray skin covered with papillae. The thick (up to 30 mm), immobile skin covers the majority of the body, while bumpy skin covers areas that require a lot of movement. Smooth skin can be found on delicate areas of the body. Hair that varies in color, length, and thickness can be found along the body. Hair that grows along the back and tail is flattened dark hair that can grow to 0.80 m in length. Hair around the eyes is long in order to prevent foreign objects from entering the eyes. Calves have different hair coloring and texture. Their hair is softer with a lighter tone such as a red or brown.

The dental formula for African elephants is i 1/0, c 0/0, p 3/3, m 3/3. At birth, calves do not have tusks but instead have temporary premaxillary incisors. These incisors are replaced at about a year of age with incisors that will ultimately form the tusks. Adult African elephants have lophodont dentition, with 6 molars that grow and move forward, like on a conveyor belt. They are worn down, lost, and replaced throughout their lives. Once the sixth set of molars is worn down, there are no additional teeth to replace them and the elephant is not able to process forage. (Laursen and Bekoff, 1978; Nowak, 1999)

  • Range mass
    2000 to 6100 kg
    4405.29 to 13436.12 lb
  • Range length
    2.2 to 4 m
    7.22 to 13.12 ft

Reproduction

The estrus state is how bulls know if cows are ready to mate. This is done by a scent in female urine and genital area. During the courtship process, bulls approach females and attempts to use their trunk to stroke her. Bulls will put up a fight in order to mate, by chasing the females if they retreat. When females stop retreating, they will join the bulls in stroking each other with their trunks. The courtship continues by females surrendering their hindquarters to the males. Bulls then mount the females to begin mating. The males will thrust repeatedly into the females for up to 2 mins. While females are in an estrus state, they may mate with several different bulls, and are considered polygynandrous. They are cooperative breeders, in which females have help raising young by other members of the family or "clan." (Laursen and Bekoff, 1978; Poole, et al., 2007)

African elephants are viviparous animals, meaning that they birth their young live. They breed year-round with no seasonal differences. The number of offspring is usually limited to one for each birthing period but in rare cases, twins may be born. They breed once every 3-9 years, and will give birth to an average of four calves in their lifetime. The gestation period is about 22 months but is strongly influenced by environmental factors. The gestation period may be shorter if the environmental factors are favorable for newborns survival. Newborn African elephants will weigh between 90-120 kg, with 100 kg being the average birth weight. Offspring are completely dependent on their mother's milk until they are weaned at four months, but continue to occasionally drink their mother's milk for up to three years. Young African elephants will gain their full independence around eight years of age. Sexual maturity occurs at different ages for males and females. Males will reach sexual maturity around 20 years of age, while females will reach sexual maturity around 11 years of age. (Hildebrandt, et al., 2006; Laursen and Bekoff, 1978; Poole, et al., 2007)

  • Breeding interval
    African elephants breed once every 3-9 years
  • Breeding season
    African elephants breed throughout the year
  • Range number of offspring
    1 to 2
  • Average number of offspring
    1
  • Average number of offspring
    1
    AnAge
  • Average gestation period
    22 months
  • Average gestation period
    670 days
    AnAge
  • Average weaning age
    4 months
  • Average time to independence
    8 years
  • Average age at sexual or reproductive maturity (female)
    11 years
  • Average age at sexual or reproductive maturity (female)
    Sex: female
    4018 days
    AnAge
  • Average age at sexual or reproductive maturity (male)
    20 years
  • Average age at sexual or reproductive maturity (male)
    Sex: male
    3650 days
    AnAge

In African elephant herds, primarily the mother and other females assist in taking care of the young. When female elephants give birth, they will move away from the herd in order to allow space for the offspring. When they return, all members of the herd will inspect the new elephant thoroughly. Until young elephants are around 4 years of age, they will closely follow their mother. During this time, mothers will feed their young through breast milk and help them move around obstacles. Until young offspring are independent, around 8 years of age, they will depend on the rest of the herd to teach them how to use their trunks, forage for food, and move around tough obstacles. Maternal position only affects the young if the mother is the leader of the herd, in which case, the young will be the next leader of the herd. (Laursen and Bekoff, 1978; Miller and Andrews, 2013)

  • Parental Investment
  • female parental care
  • pre-hatching/birth
    • provisioning
      • female
  • pre-weaning/fledging
    • provisioning
      • female
    • protecting
      • female
  • pre-independence
    • provisioning
      • female
    • protecting
      • female
  • post-independence association with parents
  • extended period of juvenile learning
  • maternal position in the dominance hierarchy affects status of young

Lifespan/Longevity

African elephants reportedly have been known to live up to a maximum of 65 years in captivity. However, unpublished reports have stated that African elephants may live up to 80 years in captivity. In the wild, African elephants live for an average of 60-70 years. (Carey and Judge, 2000; Nowak, 1999; Weigl, 2005; Wiese and Willis, 2004)

Behavior

African elephants generally are slow moving creatures. Their regular pace is 6 km/hour but, they can reach speeds of up to 24 km/hour when running. How much they travel each day depends on the amount of resources in close proximity that they require; the average walking distance for African elephants is around 10 km a day. Before African elephant populations were constricted to large reservations for protection, they migrated hundreds of kilometers seasonally, from high to low altitudes and vice versa.

African elephants are active animals for the majority of time in a 24-hour period, due to the amount of food they must consume each day. They are dormant in the early morning hours with an additional sleep midday for a total of 4 hours of sleep every day. During this time they scavenge for food and groom themselves. Grooming consist of African elephants using their trunks to cover themselves with mud or water, and the process helps them maintain hydration.

Female African elephants are social animals that live in herds of 6 to 70 members. These herds have a matriarchal order, and consist of females (cows) and their young. The alpha elephant in these herds tends to be the biggest and most dominant. Male African elephants (bulls) tend to only live within a herd if they are not old enough to go out on their own or for mating purposes. Bulls will live a life in solitary or with a few other bulls. (Greco, et al., 2016; Laursen and Bekoff, 1978; Lee and Moss, 2012; Miller, et al., 2016; Thouless, 1996)

Home Range

If enough essential resources are present African elephants will move as little as 1.5 Km a day. When resources are scarce, African elephants may travel as much as 40 km a day. Thouless (1996) reported that African elephants' home range can vary from 102 to 5527 km within a period of 25 months. (Miller, et al., 2016)

Communication and Perception

African elephants communicate acoustically with others of their species. Many of their calls are low frequency calls of ca. 20Hz. They can make a variety of calls including rumble, trumpet, snort, roar, bark, and grunt. Soltis (2010) reports 3 other calls made by these elephants. They include "rev, croak, and chuff." A trumpet, roar, or growl could show signs of aggression. A "soft chirp" shows submission or intimidation. Infant elephants will gurgle during play and squeal when frightened. The African elephants can hear one of these calls from over 2km away. They will make these calls to warn or gather others in their herd or to signal they are ready to mate. African elephants watch and listen to their surrounding environment for signs of something amiss. They communicate visually by using their trunks or ears to signal other herd members. Tactile communication is between a mother and her child or two elephants trying to mate. Forms of chemical communication along with scent marking among African elephants is done by males who are mating with the females in a clan. Around the clan the males will mark trees or bushes with their tusks or by secreting a substance onto the bush. (Laursen and Bekoff, 1978; O’Connell-Rodwell, et al., 2006; Soltis, 2010)

Food Habits

African elephants have a herbivorous diet consisting of tree foliage, fruits, herbs, grasses, and wood including roots, twigs, and bark. Their source of fiber comes from chewing on bark but not digesting the bark itself. In order to obtain bark or roots, African elephants will overturn a tree to for easier access. Using their trunks as a temporary container or holding, African elephants use their trunks to gather water and shoot it into their mouths. African elephants will feed continuously throughout the day, eating opportunistically. They must consume around 50 gallons of water everyday in order to stay hydrated.

African elephants are both browsers and grazers. Depending on the season and location, herds may depend more on one or the other feeding technique. Typically during the wet seasons, African elephants are more particular about they consume. During this season, they are more likely to forage on grasses. However, during the dry seasons when food is less abundant, they will be more flexible with what they consume. During both seasons, African elephants tend to pick food sources that are high in nutritional content. (Archie, et al., 2006; Chafota and Owen-Smith, 2012; Codron, et al., 2006; Codron, et al., 2013; Laursen and Bekoff, 1978)

  • Plant Foods
  • leaves
  • roots and tubers
  • wood, bark, or stems
  • fruit

Predation

Due to their size, African elephants are not easy prey for many predators. While lions (Panthera leo), wild dogs (Lycaon pictus), hyenas (Crocuta crocuta), and Nile crocodiles (Crocodilus niloticus) are predators of African elephants, the majority of these predators prey on the young elephants that lag behind the rest of their group. These predators will attempt to hunt elephants at night, due to the safety level decreasing because the herd cannot see well at night. However, these predators are not the problem for the African elephant population. Humans (Homo sapiens) hunt these creatures for their ivory tusks and leathery skin. (Joubert, 2006; Laursen and Bekoff, 1978)

Ecosystem Roles

African elephants are thought to be a keystone species, because in small numbers, they have lasting impacts. They often are labelled as bioengineers. For example, their destruction or altering of trees positively influences herpetofaunal diversity, as they create more three-dimensional habitat diversity for these herps.

There are many parasitic species that use African elephants as their host. There is a wide variety to the kind of parasites that infect African elephants such as flukes (Protofasciola robusta), ticks, blood sucking flies (Anthomyidae), roundworms (Strongyloides papillosus, Haemonchus contortus, Trichostrongylus colubriformis, Murshidia, Oesophagostomum columbianum), lice, botflies (Pharyngobolus africanus, Platycobboldia loxodontis, Rodhainomyia roverei, Ruttenia loxodontis, Neocuterebra squamosa>>), warble flies (Hypoderma), protozoan parasites (Babesia, Eimeria bovis), and hookworms (Ancylostoma duodenale). African elephants do have a mutualistic relationship with birds, as the birds will feed on the skin parasites of the elephants, providing them a meal while ridding the elephants of some parasites.

White egrets Bubulcus ibis may have a mutualistic rlationship with African elephants. These species often are seen together, with the egret below or atop the elephant. The presumption is that the birds are feeding on parasites. (Baines, et al., 2015; Laursen and Bekoff, 1978; McLean, et al., 2012; Nasseri, et al., 2011; Zumpt and Wetzel, 1970)

Mutualist Species
Commensal/Parasitic Species
  • warble flies (Hypoderma)
  • blood sucking flies (Anthomyidae)
  • roundworms (Murshidia)
  • roundworms (Oesophagostomum columbianum)
  • roundworms (Strongyloides papillosus)
  • roundworms (Haemonchus contortus)
  • roundworms (Trichostrongylus colubriformis)
  • flukes (Protofasciola robusta)
  • botflies (Pharyngobolus africanus)
  • botflies (Platycobboldia loxodontis)
  • botflies (Rodhainomyia roverei)
  • botflies (Ruttenia loxodontis)
  • botflies (Neocuterebra squamosa)
  • protozoan parasites (Eimeria bovis)
  • protozoan parasites (Babesia)
  • lice (Siphonaptera)
  • ticks (Acari)

Economic Importance for Humans: Positive

African elephants are used for a variety of reasons that benefit humans, often involving the killing of these elephants. African elephants can simply be used as large sport hunting for trophies or they can be hunted for their tusks, ears, feet, and meat. Because their tusks are made of ivory, they have been used for numerous reasons such as billiard balls, dice, piano keys, and most commonly, decorative carvings. Ivory can be sold for a high price, allowing someone to live off the price of a few pounds. Their large ears are converted into leather to make purses. Their feet can be preserved and made into furniture. However, given the conservation status of African elephants, these uses of elephant parts are difficult to justify. (Laursen and Bekoff, 1978; Wittemyer, 2011; Gao and Clark, 2014; Laursen and Bekoff, 1978; Wittemyer, 2011)

  • Positive Impacts
  • food
  • body parts are source of valuable material

Economic Importance for Humans: Negative

African elephants do not have many negative economic impacts on humans. African elephants destroy vegetation by using it as a food source or by knocking it down due to their massive size. If elephants are raiding crops for food and people come to stop them, the elephants might chase down the people and kill them. (Gadd, 2005; Laursen and Bekoff, 1978; Thomas, et al., 2008)

  • Negative Impacts
  • injures humans

Conservation Status

According to the IUCN Red List, African elephants are listed as a "Vulnerable" species. CITES appendices list African elephants in both Appendix I and Appendix II. African elephants in Botswana, Namibia, South Africa, and Zimbabwe are listed in Appendix II, while African elephants in other countries are listed in Appendix I. Appendix I means the species is in danger of extinction. This Appendix protects the species by making international trade illegal when dealing with African elephants. Appendix II states that the species is not endangered, but could become so if poaching is not regulated. The US Federal List have listed African elephants as a "Threatened" species.

The reason some elephant populations are in decline in certain countries is because hunting is legal in these countries. However, illegal poaching that is not prosecuted has the same negative impact. Elephants are sold and bought legally or illegally for their hides, fur, tusks, and meat. Despite an international ban on the sale of ivory since 1989, trade in illegal ivory doubled from 2007-2014. Organized crime combined with corrupt government officials makes it increasingly difficult to punish offenders.

Another reason for the decline of African elephants is that they are losing their habitats due to human development and expansion.

In order to combat further decline of African elephants, some populations have been moved to protected areas to prevent poaching. However, about 70% of the current range is unprotected lands. So, threats are on-going. Some management efforts have been successful at increasing local populations, so much so that contraception or trap-and-relocate programs had to be implemented to sustain the habitat. Another hardship is that herds are treated differently across political boundaries - the legality of hunting, the locals' attitudes towards elephants, and the permissability of or non-action to combat illegal poaching all affect the populations. Larger-scale conservation plans that cross country boundaries may address some of these issues. (Bennett, 2015; Blanc, 2008; Laursen and Bekoff, 1978)

Contributors

Meghan Howard (author), Radford University, Karen Powers (editor), Radford University, Alex Atwood (editor), Radford University, Marisa Dameron (editor), Radford University, Tanya Dewey (editor), University of Michigan-Ann Arbor.

Glossary

Ethiopian

living in sub-Saharan Africa (south of 30 degrees north) and Madagascar.

World Map

acoustic

uses sound to communicate

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

chemical

uses smells or other chemicals to communicate

colonial

used loosely to describe any group of organisms living together or in close proximity to each other - for example nesting shorebirds that live in large colonies. More specifically refers to a group of organisms in which members act as specialized subunits (a continuous, modular society) - as in clonal organisms.

cooperative breeder

helpers provide assistance in raising young that are not their own

desert or dunes

in deserts low (less than 30 cm per year) and unpredictable rainfall results in landscapes dominated by plants and animals adapted to aridity. Vegetation is typically sparse, though spectacular blooms may occur following rain. Deserts can be cold or warm and daily temperates typically fluctuate. In dune areas vegetation is also sparse and conditions are dry. This is because sand does not hold water well so little is available to plants. In dunes near seas and oceans this is compounded by the influence of salt in the air and soil. Salt limits the ability of plants to take up water through their roots.

diurnal
  1. active during the day, 2. lasting for one day.
dominance hierarchies

ranking system or pecking order among members of a long-term social group, where dominance status affects access to resources or mates

endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

female parental care

parental care is carried out by females

fertilization

union of egg and spermatozoan

folivore

an animal that mainly eats leaves.

food

A substance that provides both nutrients and energy to a living thing.

frugivore

an animal that mainly eats fruit

herbivore

An animal that eats mainly plants or parts of plants.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

keystone species

a species whose presence or absence strongly affects populations of other species in that area such that the extirpation of the keystone species in an area will result in the ultimate extirpation of many more species in that area (Example: sea otter).

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

nocturnal

active during the night

nomadic

generally wanders from place to place, usually within a well-defined range.

polygynandrous

the kind of polygamy in which a female pairs with several males, each of which also pairs with several different females.

rainforest

rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.

scent marks

communicates by producing scents from special gland(s) and placing them on a surface whether others can smell or taste them

scrub forest

scrub forests develop in areas that experience dry seasons.

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

sexual ornamentation

one of the sexes (usually males) has special physical structures used in courting the other sex or fighting the same sex. For example: antlers, elongated tails, special spurs.

social

associates with others of its species; forms social groups.

tactile

uses touch to communicate

terrestrial

Living on the ground.

threatened

The term is used in the 1994 IUCN Red List of Threatened Animals to refer collectively to species categorized as Endangered (E), Vulnerable (V), Rare (R), Indeterminate (I), or Insufficiently Known (K) and in the 1996 IUCN Red List of Threatened Animals to refer collectively to species categorized as Critically Endangered (CR), Endangered (EN), or Vulnerable (VU).

tropical

the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.

tropical savanna and grassland

A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.

savanna

A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.

temperate grassland

A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.

visual

uses sight to communicate

viviparous

reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.

year-round breeding

breeding takes place throughout the year

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