African bush elephant

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African bush elephant
Temporal range: Pleistocene–Recent
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An elephant in Kruger National Park.jpg
Adult in Kruger National Park, South Africa
CITES Appendix I (CITES) [1] [note 1]
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Proboscidea
Family: Elephantidae
Genus: Loxodonta
Species:
L. africana [2]
Binomial name
Loxodonta africana [2]
(Blumenbach, 1797)
Subspecies

See text

LoxodontaAfricanaIUCN.svg
Range of the African bush elephant
  Resident
  Possibly resident
  Possibly extinct
  Resident and reintroduced
Synonyms

Elephas africanus

The African bush elephant (Loxodonta africana), also known as the African savanna elephant, is a species of elephant native to sub-Saharan Africa. It is one of three extant elephant species and, along with the African forest elephant, one of two extant species of African elephant. It is the largest living terrestrial animal, with fully grown bulls reaching an average shoulder height of 3.04–3.36 metres (10.0–11.0 ft) and a body mass of 5.2–6.9 tonnes (11,000–15,000 lb); the largest recorded specimen had a shoulder height of 3.96 metres (13.0 ft) and an estimated body mass of 10.4 tonnes (23,000 lb). The African bush elephant is characterised by its long prehensile trunk with two finger-like processes; a convex back; large ears which help reduce body heat; and sturdy tusks that are noticeably curved. The skin is grey with scanty hairs, and bending cracks which support thermoregulation by retaining water.

Contents

The African bush elephant inhabits a variety of habitats such as forests, grasslands, woodlands, wetlands and agricultural land. It is a mixed herbivore feeding mostly on grasses, creepers, herbs, leaves, and bark. The average adult consumes about 150 kg (330 lb) of vegetation and 230 L (51 imp gal; 61 US gal) of water each day. A social animal, the African bush elephant often travels in herds composed of cows and their offspring. Adult bulls usually live alone or in small bachelor groups. During the mating season, males go through a process called musth; a period of high testosterone levels and heightened aggression. For females, the menstrual cycle lasts three to four months, and gestation around 22 months, the longest of any mammal.

Since 2021, the African bush elephant has been listed as Endangered on the IUCN Red List. It is threatened foremost by habitat destruction, and in parts of its range also by poaching for meat and ivory. Between 2003 and 2015, the illegal killing of 14,606 African bush elephants was reported by rangers across 29 range countries. Chad is a major transit country for smuggling of ivory in West Africa. This trend was curtailed by raising penalties for poaching and improving law enforcement. Poaching of the elephant has dated back to the 1970s and 80s, which were considered the largest killings in history. In human culture, elephants have been extensively featured in literature, folklore and media, and are most valued for their large tusks in many places.

Taxonomy and evolution

In the 19th and 20th centuries, several zoological specimens were described by naturalists and curators of natural history museums from various parts of Africa, including:

Today, these names are all considered synonyms. [2]

A genetic study based on mitogenomic analysis revealed that the African and Asian elephant genetically diverged about 7.6 million years ago. [6] Phylogenetic analysis of nuclear DNA of African bush and forest elephants, Asian elephant, woolly mammoth, and American mastodon revealed that the African bush elephant and the African forest elephant form a sister group that genetically diverged at least 1.9 million years ago. They are therefore considered distinct species. Gene flow between the two species, however, might have occurred after the split. [7] Some authors have suggested thatL. africana evolved from Loxodonta atlantica . [8]

The fossil record for L. africana is sparse. The earliest possible records of the species are from the Shungura Formation around Omo in Ethiopia, which are dated to the Early Pleistocene, around 2.44-2.27 million years ago. [9] Another possible early record is from the Kanjera site in Kenya, dating to the Middle Pleistocene, around 500,000 years ago. [10] [11] Genetic analysis suggests a major population expansion between 500,000 and 100,000 years ago. [11] Records become more common during the Late Pleistocene, following the extinction of the last African Palaeoloxodon elephant species, Palaeoloxodon jolensis . [11]

Description

The African bush elephant has grey skin with scanty hairs. Its large ears cover the whole shoulder, [12] and can grow as large as 2 m × 1.5 m (6 ft 7 in × 4 ft 11 in). [13] Its large ears help to reduce body heat; flapping them creates air currents and exposes large blood vessels on the inner sides to increase heat loss during hot weather. [14] The African bush elephant's ears are pointed and triangular shaped. Its occipital plane slopes forward. Its back is shaped markedly concave. Its sturdy tusks are curved out and point forward. [15] Its long trunk or proboscis ends with two finger-like tips. [16]

Size

Average size of adults with the largest recorded individual included African-Elephant-Scale-Chart-SVG-Steveoc86.svg
Average size of adults with the largest recorded individual included

The African bush elephant is the largest and heaviest living land animal. Under optimal conditions where individuals are capable of reaching full growth potential, fully grown mature males are about 3.20 m (10.5 ft) tall at the shoulder and weigh 6.0 t (6.6 short tons) on average (with 90% of fully grown males under optimal conditions being between 3.04–3.36 m (10.0–11.0 ft) and 5.2–6.9 t (5.7–7.6 short tons)). Mature fully grown females are smaller at about 2.60 m (8 ft 6 in) tall at the shoulder and 3.0 t (3.3 short tons) in weight on average under optimal growth conditions (with 90% of fully grown females ranging between 2.47–2.73 m (8 ft 1 in – 8 ft 11 in) and 2.6–3.5 t (2.9–3.9 short tons) in optimal conditions). [17] [18] [19] [20] The maximum recorded shoulder height of an adult bull is 3.96 m (13.0 ft), with this individual having an estimated weight of 10.4 t (11.5 short tons). [17] Elephants attain their maximum stature when they complete the fusion of long-bone epiphyses, occurring in males around the age of 40 and females around 25 years of age. [17]

Dentition

The dental formula of the African bush elephant is 1.0.3.30.0.3.3 × 2 = 26. They develop six molars in each jaw quadrant that erupt at different ages and differ in size. [21] The first molars grow to a size of 2 cm (0.79 in) wide by 4 cm (1.6 in) long, are worn by the age of one year and lost by the age of about 2.5 years. The second molars start protruding at the age of about six months, and grow to a size of 4 cm (1.6 in) wide by 7 cm (2.8 in) long and are lost by the age of 6–7 years. The third molars protrude at the age of about one year, grow to a size of 5.2 cm (2.0 in) wide by 14 cm (5.5 in) long, and are lost by the age of 8–10 years. The fourth molars show by the age of 6–7 years, grow to a size of 6.8 cm (2.7 in) wide by 17.5 cm (6.9 in) long and are lost by the age of 22–23 years. The dental alveoli of the fifth molars are visible by the age of 10–11 years. They grow to a size of 8.5 cm (3.3 in) wide by 22 cm (8.7 in) long and are worn by the age of 45–48 years. The dental alveoli of the last molars are visible by the age of 26–28 years. They grow to a size of 9.4 cm (3.7 in) wide by 31 cm (12 in) long and are well worn by the age of 65 years. [22]

Molar of an adult African bush elephant Loxodonta africana - Molar of an adult.JPG
Molar of an adult African bush elephant

Both sexes have large, curved, maxillary incisors known as tusks that continue growing throughout their lives. In the wild, a large percentage of elephants experience a tusk fracture, although this is more prevalent in captivity. A tusk fracture of any sort usually results in serious infections, as the pulp is exposed to the elements. [23] The tusks erupt when they are 1–3 years old. [21] Tusks grow from deciduous teeth known as tushes that develop in the upper jaw and consist of a crown, root and pulpal cavity, which are completely formed soon after birth. Tushes reach a length of 5 cm (2.0 in). [24] They are composed of dentin and coated with a thin layer of cementum. Their tips bear a conical layer of enamel that is usually worn off when the elephant is five years old. [25] Tusks of bulls grow faster than tusks of cows. Mean weight of tusks at the age of 60 years is 109 kg (240 lb) in bulls and 17.7 kg (39 lb) in cows. [21] The longest known tusk of an African bush elephant measured 3.51 m (11.5 ft) and weighed 117 kg (258 lb). [26]

Distribution and habitat

The African bush elephant occurs in sub-Saharan Africa which includes Uganda, Kenya, Tanzania, Botswana, Zimbabwe, Namibia, Zambia, Angola, Malawi, Mali, Rwanda, Mozambique and South Africa. It moves between a variety of habitats, including subtropical and temperate forests, dry and seasonally flooded grasslands, woodlands, wetlands, and agricultural land from sea level to mountain slopes. In Mali and Namibia, it also inhabits desert and semi-desert areas. [1]

Populations of African bush elephants are increasing in some areas such as the Kruger National Park, where an annual growth of 4.2% was recorded between 2003 and 2015. [27] There are estimated to be at least 17,000 elephants in the park's vicinity, as of 2015–the most of any area in South Africa. [28] [29] The increase in population occurred after the discontinuation of culling in the mid-1990s. [30] This large elephant population is considered a problem to both the environment and its creatures. As such, with the use of natural processes, conservationists aim to control the ever-growing population. [31] [28] In other places in southern Africa, the elephant population continues to increase. [32] Botswana in particular hosts more African bush elephants than any other country, at 130,000. [33] In a 2019 study, populations were found to be steady, though the authors also noted an unusual increase in carcasses, possibly due to a new wave of poaching which was uncommon at the time. [34]

In East Africa there are roughly 137,000 elephants distributed across six countries in a wide array of habitats, such as grasslands and woodlands. They are most threatened by illegal hunting activities, such as poaching. In one instance, between 2006 and 2013, the population in East Africa fell by 62% due to high poaching pressures. Tanzania (where 80% of the East African population reside) lost the most elephants, while the resident population in Somalia went locally extinct. South Sudan, on the other hand, experienced an increase in elephants. Following successful conservation and governmental actions, Kenya also saw an increase in their elephant numbers. [35] In Ethiopia, the African bush elephant has historically been recorded up to an elevation of 2,500 m (8,200 ft). By the late 1970s, the population had declined to one herd in the Dawa River valley and one close to the Kenyan border. [36] As of 2015, there are estimated to be 1,900–2,151 elephants in the country, a decrease from 6,000–10,000 in the 1970s. It is estimated that between the 1980s and 2010s, elephants in Ethiopia experienced a decline of around 90%–hence the endangered assessment. [35]

In West and Central Africa, the population of elephants are threatened, in large part due to habitat loss and fragmentation, and rapid growth in human populations. Elephants occur in isolated pockets throughout the region and are for the most part decreasing in number. [37]

Behavior and ecology

Social behavior

Herd of Elephants.jpg
Elephant family in Amboseli National Park, Kenya
Down the water hole.jpg
Young bulls in a bachelor group in Hwange National Park, Zimbabwe

The core of elephant society is the family unit, which mostly comprises several adult cows, their daughters, and their prepubertal sons. Iain Douglas-Hamilton, who observed African bush elephants for 4.5 years in Lake Manyara National Park, coined the term 'kinship group' for two or more family units that have close ties. The family unit is led by a matriarch who at times also leads the kinship group. [38] [39] Groups cooperate in locating food and water, in self-defense, and in caring for offspring (termed allomothering). [38] Group size varies seasonally and between locations. In Tsavo East and Tsavo West National Parks, groups are bigger in the rainy season and areas with open vegetation. [40] Aerial surveys in the late 1960s to early 1970s revealed an average group size of 6.3 individuals in Uganda's Rwenzori National Park and 28.8 individuals in Chambura Game Reserve. In both sites, elephants aggregated during the wet season, whereas groups were smaller in the dry season. [41]

Young bulls gradually separate from the family unit when they are between 10 and 19 years old. They range alone for some time or form all-male groups. [42] A 2020 study highlighted the importance of old bulls for the navigation and survival of herds and raised concerns over the removal of old bulls as "currently occur[ring] in both legal trophy hunting and illegal poaching". [43]

Temperature regulation

The African bush elephant has curved skin with bending cracks, which support thermoregulation by retaining water. [44] These bending cracks contribute to an evaporative cooling process which helps to maintain body temperature via homeothermy regardless of air temperature. [45]

Diet

A bull elephant stretching up to break off a tree branch in the Okavango Delta, Botswana African elephant (Loxodonta africana) reaching up 3.jpg
A bull elephant stretching up to break off a tree branch in the Okavango Delta, Botswana

The African bush elephant is herbivorous. It is a mixed feeder, consuming both grasses, as well as woody vegetation (browse), with the proportions varying wildly depending on the habitat and time of year, ranging from almost exclusively grazing to near-total browsing. [46] African bush elephants' consumption of woody plants, particularly their habit of uprooting trees, has the ability to alter the local environment, transforming woodlands into grasslands. [47] African bush elephants also at times consume fruit and serve as seed dispersers. [48] Adults can consume up to 150 kg (330 lb) of food per day. [49] To supplement their diet with minerals, they congregate at mineral-rich water holes, termite mounds, and mineral licks. [50] Salt licks visited by elephants in the Kalahari contain high concentrations of water-soluble sodium. [51] Elephants drink 180–230 litres (50–60 US gal) of water daily, and seem to prefer sites where water and soil contain sodium. In Kruger National Park and on the shore of Lake Kariba, elephants were observed to ingest wood ash, which also contains sodium. [52]

Communication

Africa bush elephants use their trunks for tactile communication. When greeting, a lower ranking individual will insert the tip of its trunk into its superior's mouth. Elephants will also stretch out their trunk toward an approaching individual they intend to greet. Mother elephants reassure their young with touches, embraces, and rubbings with the foot while slapping disciplines them. During courtship, a couple will caress and intertwine with their trunks while playing and fighting individuals wrestle with them. [53]

Elephant vocals are variations of rumbles, trumpets, squeals, and screams. Rumbles are mainly produced for long-distance communication and cover a broad range of frequencies which are mostly below what a human can hear. Infrasonic rumbles can travel vast distances and are important for attracting mates and scaring off rivals. [53]

Growls are audible rumbles and happen during greetings. When in pain or fear, an elephant makes an open-mouthed growl known as a bellow. A drawn-out growl is known as a moan. Growling can escalate into a roaring when the elephant is issuing a threat. Trumpeting is made by blowing through the trunk and signals excitement, distress, or aggression. Juvenile elephants squeal in distress while screaming is done by adults for intimidation. [53]

Musth

Bull in musth African Elephant (Loxodonta africana) eye close-up showing the Musth gland opening (16689303126).jpg
Bull in musth

Bulls in musth experience swelling of the temporal glands and secretion of fluid, the musth fluid, which flows down their cheeks. They begin to dribble urine, initially as discrete drops and later in a regular stream. These manifestations of musth last from a few days to months, depending on the age and condition of the bull. When a bull has been urinating for a long time, the proximal part of the penis and the distal end of the sheath show a greenish coloration, termed the 'green penis syndrome' by Joyce Poole and Cynthia Moss. [54] Males in musth become more aggressive. They guard and mate with females in estrus, who stay closer to bulls in musth than to non-musth bulls. [55] Urinary testosterone increases during musth. [56] Bulls begin to experience musth by the age of 24 years. Periods of musth are short and sporadic in young bulls up to 35 years old, lasting a few days to weeks. Older bulls are in musth for 2–5 months every year. Musth occurs mainly during and following the rainy season when females are in estrus. [57] Bulls in musth often chase each other and are aggressive towards other bulls in musth. When old and high-ranking bulls in musth threaten and chase young musth bulls, either the latter leave the group or their musth ceases. [58]

Young bulls in musth killed about 49 white rhinoceros in Pilanesberg National Park between 1992 and 1997. This unusual behavior was attributed to their young age and inadequate socialisation; they were 17–25-year-old orphans from culled families that grew up without the guidance of dominant bulls. When six adult bulls were introduced into the park, the young bulls did not attack rhinos anymore, indicating older bulls suppress the musth and aggressiveness of younger bulls. [59] [60] Similar incidents were recorded in Hluhluwe-Umfolozi Park, where young bulls killed five black and 58 white rhinoceros between 1991 and 2001. After the introduction of ten bulls, each up to 45 years old, the number of rhinos killed by elephants decreased considerably. [61]

Reproduction

Elephant (Loxodonta africana) mating ritual composite.jpg
Mating ritual in Addo Elephant Park
African bush elephants (Loxodonta africana) female with six-week-old baby.jpg
Cow with six-week-old calf in Zimbabwe
African bush elephant (Loxodonta africana) baby 6 weeks.jpg
Calf of six weeks in Zimbabwe

Spermatogenesis starts when bulls are about 15 years old. [62] However, males have not begun sexual cycles, not experiencing their first musth period until they are 25 or 30 years of age. [63] Cows ovulate for the first time at the age of 11 years. [64] They are in estrus for 2–6 days. [65] In captivity, cows have an oestrous cycle lasting 14–15 weeks. Foetal gonads enlarge during the second half of pregnancy. [66]

African bush elephants mate during the rainy season. [64] Bulls in musth cover long distances in search of cows and associate with large family units. They listen for the cows' loud, very low frequency calls and attract cows by calling and by leaving trails of strong-smelling urine. Cows search for bulls in musth, listen for their calls, and follow their urine trails. [67] Bulls in musth are more successful at obtaining mating opportunities than those who are not. A cow may move away from bulls that attempt to test her estrous condition. If pursued by several bulls, she will run away. Once she chooses a mating partner, she will stay away from other bulls, which are threatened and chased away by the favoured bull. Competition between bulls sometimes overrides the cow's choice of mating partner. [65] After the mating period, females will undergo a gestation of 22 months. The interval between births was estimated at 3.9 to 4.7 years in Hwange National Park. [64] Where hunting pressure on adult elephants was high in the 1970s, cows gave birth once in 2.9 to 3.8 years. [68] Cows in Amboseli National Park gave birth once in 5 years on average. [65]

The birth of a calf was observed in Tsavo East National Park in October 1990. A group of 80 elephants including eight bulls had gathered in the morning in a 150 m (490 ft) radius around the birth site. A small group of calves and cows stood near the pregnant cow, rumbling and flapping their ears. One cow seemed to assist her. While she was in labour, fluid streamed from her temporal and ear canals. She remained standing while giving birth. The newborn calf struggled to its feet within 30 minutes and walked 20 minutes later. The mother expelled the placenta about 100 minutes after birth and covered it with soil immediately. [69]

Captive-born calves weigh between 100 and 120 kg (220 and 260 lb) at birth and gain about 0.5 kg (1.1 lb) weight per day. [70] Cows lactate for about 4.8 years. [71] Calves exclusively suckle their mother's milk during the first three months. Thereafter, they start feeding independently and slowly increase the time spent feeding until they are two years old. During the first three years, male calves spend more time suckling and grow faster than female calves. After this period, cows reject male calves more frequently from nursing than female calves. [72]

The maximum lifespan of the African bush elephant is between 70 and 75 years. [73] Its generation length is 25 years. [74]

Predators

Adult elephants are considered invulnerable to predation. [75] Calves, usually under two years, are sometimes preyed on by lions and spotted hyenas. [16] Adult elephants often chase off predators, especially lions, by mobbing behavior. [76] Juveniles are usually well defended by protective adults though serious drought makes them vulnerable to lion predation. [77]

In Botswana's Chobe National Park, lions attacked and fed on juvenile and subadult elephants during the drought when smaller prey species were scarce. Between 1993 and 1996, lions successfully attacked 74 elephants; 26 were older than nine, and one was a bull of over 15 years. Most were killed at night, and hunts occurred more often during waning moon nights than during bright moon nights. [78] In the same park, lions killed eight elephants in October 2005 that were aged between 1 and 11 years, two of them older than 8 years. Successful hunts took place after dark when prides exceeded 27 lions and herds were smaller than 5 elephants. [79]

Pathogens

Observations at Etosha National Park indicate that African bush elephants die due to anthrax foremost in November at the end of the dry season. [80] Anthrax spores spread through the intestinal tracts of vultures, jackals and hyaenas that feed on the carcasses. Anthrax killed over 100 elephants in Botswana in 2019. [81] It is thought that wild bush elephants can contract fatal tuberculosis from humans. [82] Infection of the vital organs by Citrobacter freundii bacteria caused the death of an otherwise healthy bush elephant after capture and translocation. [83]

From April to June 2020, over 400 bush elephants died in Botswana's Okavango Delta region after drinking from desiccating waterholes that were infested with cyanobacteria. [84] Neurotoxins produced by the cyanobacteria caused calves and adult elephants to wander around confused, emaciated and in distress. The elephants collapsed when the toxin impaired their motor functions and their legs became paralysed. Poaching, intentional poisoning, and anthrax were excluded as potential causes. [85]

Elephants may also be host for a variety of parasites and bacteria such as Pasteurella , [86] Salmonella , Clostridium, [87] coccidian, nematode, and trematode. [88] The elephant endotheliotropic herpesvirus (EEHV) is a member of the Proboscivirus genus, a novel clade most closely related to the mammalian betaherpesviruses. [89] In benign infections found in some wild and captive African elephants, these viruses can affect either the skin or the pulmonary system. [90]

Intelligence

Both African and Asian elephants have a very large and highly complex neocortex, a trait also shared by humans, apes and certain dolphin species. [91] Elephants manifest a wide variety of behaviors, including those associated with grief, learning, mimicry, playing, altruism, tool use, compassion, cooperation, self-awareness, memory, and communication. [92] [93] [94] In a 2013 study, it was suggested that elephants may understand pointing, the ability to nonverbally communicate an object by extending a finger, or equivalent. [95] The intelligence of elephants is described as being on a par with that of cetaceans, [96] and various primates. [91]

Threats

The African bush elephant is threatened primarily by habitat loss and fragmentation following conversion of natural habitat for livestock farming, plantations of non-timber crops, and building of urban and industrial areas. As a result, human-elephant conflict has increased. [1]

Poaching

An African bush elephant killed by Theodore Roosevelt Roosevelt safari elephant.jpg
An African bush elephant killed by Theodore Roosevelt

Poachers target foremost elephant bulls for their tusks, which leads to a skewed sex ratio and affects the survival chances of a population. Access of poachers to unregulated black markets is facilitated by corruption and periods of civil war in some elephant range countries. [97] During the 20th century, the African bush elephant population was decimated. [98] Poaching of the elephant has dated back to the years 1970 and 1980, which were considered the largest killings in history. The species is placed in harm's way due to the limited conservation areas provided in Africa. In most cases, the killings of the African bush elephant have occurred near the outskirts of the protected areas. [1]

Between 2003 and 2015, the illegal killing of 14,606 African bush elephants was reported by rangers across 29 range countries. Chad is a major transit country for smuggling of ivory in West Africa. This trend was curtailed by raising penalties for poaching and improving law enforcement. [99] Before this in June 2002, a container packed with more than 6.5 t (6.4 long tons; 7.2 short tons) ivory was confiscated in Singapore. It contained 42,120 hanko stamps and 532 tusks of African bush elephants that originated in Southern Africa, centered in Zambia and neighboring countries. Between 2005 and 2006, a total of 23.461 t (23.090 long tons; 25.861 short tons) ivory plus 91 unweighed tusks of African bush elephants were confiscated in 12 major consignments being shipped to Asia. [100]

When the international ivory trade reopened in 2006, the demand and price for ivory increased in Asia. The African bush elephant population in Chad's Zakouma National Park numbered 3,900 individuals in 2005. Within five years, more than 3,200 elephants were killed. The park did not have sufficient guards to combat poaching, and their weapons were outdated. Well-organized networks facilitated smuggling the ivory through Sudan. [101] Poaching also increased in Kenya in those years. [102] In Samburu National Reserve, 41 bulls were illegally killed between 2008 and 2012, equivalent to 31% of the reserve's elephant population. [103] These killings were linked to confiscations of ivory and increased prices for ivory on the local black market. [104] About 10,370 tusks were confiscated in Singapore, Hong Kong, Taiwan, Philippines, Thailand, Malaysia, Kenya and Uganda between 2007 and 2013. Genetic analysis of tusk samples showed that they originated from African bush elephants killed in Tanzania, Mozambique, Zambia, Kenya, and Uganda. Most of the ivory was smuggled through East African countries. [105]

In addition to elephants being poached, their carcasses may be poisoned by the poachers to avoid detection by vultures, which help rangers detect poaching activity by circling dead animals. This poses a threat to those vultures or birds that scavenge the carcasses. On 20 June 2019, the carcasses of two tawny eagles and 537 endangered Old World vultures including 468 white-backed vultures, 17 white-headed vultures, 28 hooded vultures, 14 lappet-faced vultures and 10 Cape vultures found dead in northern Botswana were suspected to have died after eating the poisoned carcasses of three elephants. [106] [107] [108] [109]

Intensive poaching leads to strong selection on tusk attributes; African elephants in areas with heavy poaching often have smaller tusks and a higher frequency of congenitally tuskless females, whereas congenital tusklessness is rarely if ever observed in males. [110] A study in Mozambique's Gorongosa National Park revealed that poaching during the Mozambican Civil War led to the increasing birth of tuskless females when the population recovered. [111]

Habitat changes

Vast areas in Sub-Saharan Africa were transformed for agricultural use and the building of infrastructure. This disturbance leaves the elephants without a stable habitat and limits their ability to roam freely. Large corporations associated with commercial logging and mining have fragmented the land, giving poachers easy access to the African bush elephant. [112] As human development grows, the human population faces the trouble of contact with the elephants more frequently, due to the species need for food and water. Farmers residing in nearby areas come into conflict with the African bush elephants rummaging through their crops. In many cases, they kill the elephants as soon as they disturb a village or forage upon its crops. [98] Deaths caused by browsing on rubber vine, an invasive plant, have also been reported. [83]

Conservation

African bush elephants mating in Tierpark Berlin Berlin Tierpark Friedrichsfelde 12-2015 img13 African elephant.jpg
African bush elephants mating in Tierpark Berlin

Both African elephant species have been listed on Appendix I of the Convention on International Trade in Endangered Species of Wild Fauna and Flora since 1989. In 1997, populations of Botswana, Namibia, and Zimbabwe were placed on CITES Appendix II, as were populations of South Africa in 2000. Community-based conservation programmes have been initiated in several range countries, which contributed to reducing human-elephant conflict and increasing local people's tolerance towards elephants. [1] Researchers discovered that playing back the recorded sounds of African bees is an effective method to drive elephants away from settlements. [113]

In 1986, the African Elephant Database was initiated to collate and update information on the distribution and status of elephant populations in Africa. The database includes results from aerial surveys, dung counts, interviews with local people, and data on poaching. [99]

Status

In 2008, the IUCN Red List assessed the African elephant (then considered as a single species) as vulnerable. Since 2021, the African bush elephant has individually been assessed Endangered, after the global population was found to have decreased by more than 50% over 3 generations. [114] More than 50% of its range is located outside protected areas. [1] In 2016, the global population was estimated at 415,428 ± 20,111 individuals distributed in a total area of 20,731,202 km2 (8,004,362 sq mi), of which 30% is protected. Approximately 42% of the total population lives in nine southern African countries comprising 293,447 ± 16,682 individuals; Africa's largest population lives in Botswana with 131,626 ± 12,508 individuals. [99]

In captivity

The social behavior of elephants in captivity mimics that of those in the wild. Cows are kept with other cows, in groups, while bulls tend to be separated from their mothers at a young age and are kept apart. According to Schulte, in the 1990s, in North America, a few facilities allowed bull interaction. Elsewhere, bulls were only allowed to smell each other. Bulls and cows were allowed to interact for specific purposes such as breeding. In that event, cows were more often moved to the bull than the bull to the cow. Cows are more often kept in captivity because they are easier and less expensive to house. [115]

Cultural significance

In Africa, elephants have found a prominent role in human culture since ancient times and were most priced for their ivory tusks, which were considered valuable commercial goods. [116] In Kenya, the Maasai people have been known to use elephants for their tusks and often regard them as akin to humans. They feature extensively in Maasai culture, going by the local name of Arkanjowe (a being that is large and/or powerful). According to a Maasai legend, the elephant came to be when a woman, who was on her way to her partner's place for marriage, turned her back before reaching the destination. This event caused the woman to shape-shift into an elephant. [117]

Prehistoric North Africans depicted the elephant in Paleolithic age rock art. For example, the Libyan Tadrart Acacus, a UNESCO World Heritage Site, features a rock carving of an elephant from the last phase of the Pleistocene epoch (12,000–8000 BC) [118] rendered with remarkable realism. [119] There are many other prehistoric examples, including Neolithic rock art of south Oran (Algeria), and a white elephant rock painting in 'Phillip's Cave' by the San in the Erongo region of Namibia. [120] From the Bovidian period [a] (3550–3070 BCE), elephant images by the San bushmen in the South African Cederberg Wilderness Area suggest to researchers that they had "a symbolic association with elephants" and "had a deep understanding of the communication, behaviour and social structure of elephant family units" and "possibly developed a symbiotic relationship with elephants that goes back thousands of years." [123]

See also

Notes

  1. ↑ The populations of Botswana, Namibia, South Africa, and Zimbabwe are listed in Appendix II for control of commercial trading, though they are not necessarily threatened with extinction.
  1. ↑ During the African pastoral 'Bovidian period', there were many depictions of Bovid herds, suggesting the development of animal domestication [121] During this period humans began to domesticate animals, and transition to a seminomadic lifestyle as farmers and herders. [122]

Related Research Articles

<span class="mw-page-title-main">Elephant</span> Largest living land animal

Elephants are the largest living land animals. Three living species are currently recognised: the African bush elephant, the African forest elephant, and the Asian elephant. They are the only surviving members of the family Elephantidae and the order Proboscidea; extinct relatives include mammoths and mastodons. Distinctive features of elephants include a long proboscis called a trunk, tusks, large ear flaps, pillar-like legs, and tough but sensitive grey skin. The trunk is prehensile, bringing food and water to the mouth and grasping objects. Tusks, which are derived from the incisor teeth, serve both as weapons and as tools for moving objects and digging. The large ear flaps assist in maintaining a constant body temperature as well as in communication. African elephants have larger ears and concave backs, whereas Asian elephants have smaller ears and convex or level backs.

<span class="mw-page-title-main">Ivory</span> Material derived from the tusks and teeth of animals

Ivory is a hard, white material from the tusks and teeth of animals, that consists mainly of dentine, one of the physical structures of teeth and tusks. The chemical structure of the teeth and tusks of mammals is the same, regardless of the species of origin, but ivory contains structures of mineralised collagen. The trade in certain teeth and tusks other than elephant is well established and widespread; therefore, "ivory" can correctly be used to describe any mammalian teeth or tusks of commercial interest which are large enough to be carved or scrimshawed.

<span class="mw-page-title-main">Mammoth</span> Extinct genus of mammals

A mammoth is any species of the extinct elephantid genus Mammuthus. They lived from the late Miocene epoch into the Holocene until about 4,000 years ago, with mammoth species at various times inhabiting Africa, Asia, Europe, and North America. Mammoths are distinguished from living elephants by their spirally twisted tusks and in at least some later species, the development of numerous adaptions to living in cold environments, including a thick layer of fur.

<span class="mw-page-title-main">Poaching</span> Illegal hunting of wildlife

Poaching is the illegal hunting or capturing of wild animals, usually associated with land use rights. Poaching was once performed by impoverished peasants for subsistence purposes and to supplement meager diets. It was set against the hunting privileges of nobility and territorial rulers.

<span class="mw-page-title-main">Elephantidae</span> Family of mammals

Elephantidae is a family of large, herbivorous proboscidean mammals collectively called elephants and mammoths. In some cases, all members of the family can be referred to as elephants. They are large terrestrial mammals with a snout modified into a trunk and teeth modified into tusks. Most genera and species in the family are extinct. Only two genera, Loxodonta and Elephas, are living.

<span class="mw-page-title-main">African forest elephant</span> African elephant species

The African forest elephant is one of the two living species of African elephant, along with the African bush elephant. It is native to humid tropical forests in West Africa and the Congo Basin. It is the smallest of the three living elephant species, reaching a shoulder height of 2.4 m. As with other African elephants, both sexes have straight, down-pointing tusks, which begin to grow once the animals reach 1–3 years old. The forest elephant lives in highly sociable family groups of up to 20 individuals. Since they forage primarily on leaves, seeds, fruit, and tree bark, they have often been referred to as the 'megagardener of the forest'; the species is one of many that contributes significantly to maintaining the composition, diversity and structure of the Guinean Forests of West Africa and the Congolese rainforests. Seeds of various plants will go through the elephant's digestive tract and eventually pass through in the animal's droppings, thus helping to maintain the spread and biodiversity of the forests.

<span class="mw-page-title-main">Asian elephant</span> Second largest elephant species

The Asian elephant, also known as the Asiatic elephant, is a species of elephant distributed throughout the Indian subcontinent and Southeast Asia, from India in the west to Borneo in the east, and Nepal in the north to Sumatra in the south. Three subspecies are recognised—E. m. maximus, E. m. indicus and E. m. sumatranus. The Asian elephant is characterised by its long trunk with a single finger-like processing; large tusks in males; laterally folded large ears but smaller in contrast to African elephants; and wrinkled grey skin. The skin is smoother than African elephants and may be depigmented on the trunk, ears or neck. Adult males average 4 tonnes in weight, and females 2.7 t.

<span class="mw-page-title-main">Musth</span> Condition in male elephants

Musth or must is a periodic condition in bull (male) elephants characterized by aggressive behavior and accompanied by a large rise in reproductive hormones. It has been known in Asian elephants for 3000 years but was only described in African elephants in 1981. There is evidence that similar behaviour occurred in extinct proboscideans like gomphotheres and mastodons.

<span class="mw-page-title-main">African elephant</span> Genus comprising two living elephant species

African elephants are members of the genus Loxodonta comprising two living elephant species, the African bush elephant and the smaller African forest elephant. Both are social herbivores with grey skin. However, they differ in the size and colour of their tusks as well as the shape and size of their ears and skulls.

Zakouma National Park is a 3,000 km2 (1,158 sq mi) national park in southeastern Chad, straddling the border of Guéra Region and Salamat Region. Zakouma is the nation's oldest national park, declared a national park in 1963 by presidential decree, giving it the highest form of protection available under the nation's laws. It has been managed by the nonprofit conservation organization African Parks since 2010 in partnership with Chad's government.

<span class="mw-page-title-main">Sri Lankan elephant</span> Subspecies of the Asian elephant

The Sri Lankan elephant is native to Sri Lanka and one of three recognised subspecies of the Asian elephant. It is the type subspecies of the Asian elephant and was first described by Carl Linnaeus under the binomial Elephas maximus in 1758. The Sri Lankan elephant population is now largely restricted to the dry zone in the north, east and southeast of Sri Lanka. Elephants are present in Udawalawe National Park, Yala National Park, Lunugamvehera National Park, Wilpattu National Park and Minneriya National Park but also live outside protected areas. It is estimated that Sri Lanka has the highest density of elephants in Asia. Human-elephant conflict is increasing due to conversion of elephant habitat to settlements and permanent cultivation.

<span class="mw-page-title-main">Straight-tusked elephant</span> Extinct species of elephant native to Europe and West Asia

The straight-tusked elephant is an extinct species of elephant that inhabited Europe and Western Asia during the Middle and Late Pleistocene. One of the largest known elephant species, mature fully grown bulls on average had a shoulder height of 4 metres (13 ft) and a weight of 13 tonnes (29,000 lb). Straight-tusked elephants likely lived very similarly to modern elephants, with herds of adult females and juveniles and solitary adult males. The species was primarily associated with temperate and Mediterranean woodland and forest habitats, flourishing during interglacial periods, when its range would extend across Europe as far north as Great Britain and Denmark and eastwards into Russia, while persisting in southern Europe during glacial periods. Skeletons found in association with stone tools and in one case, a wooden spear, suggest they were scavenged and hunted by early humans, including Homo heidelbergensis and their Neanderthal successors.

The 2006 Zakouma elephant slaughter refers to a series of poaching massacres of African elephants in the vicinity of Zakouma National Park in southeastern Chad. These killings were documented in aerial surveys conducted from May through August 2006 and total at least 100 animals.

<span class="mw-page-title-main">North African elephant</span> Extinct subspecies of elephant

The North African elephant is an extinct subspecies of the African bush elephant, or possibly a separate elephant species, that existed in North Africa, north of the Sahara, until it died out in Roman times. These were the famous war elephants used by Carthage in the Punic Wars, their conflict with the Roman Republic. Although the subspecies has been formally described, it has not been widely recognized by taxonomists. Other names for this animal include the North African forest elephant, Carthaginian elephant, and Atlas elephant. Its natural range probably extended along the coast of the Red Sea, in what is now Egypt, Sudan, and Eritrea, but it may have extended further across northern Africa.

<span class="mw-page-title-main">Woolly mammoth</span> Extinct species of mammoth

The woolly mammoth is an extinct species of mammoth that lived from the Middle Pleistocene until its extinction in the Holocene epoch. It was one of the last in a line of mammoth species, beginning with the African Mammuthus subplanifrons in the early Pliocene. The woolly mammoth began to diverge from the steppe mammoth about 800,000 years ago in Siberia. Its closest extant relative is the Asian elephant. The Columbian mammoth lived alongside the woolly mammoth in North America, and DNA studies show that the two hybridised with each other. Mammoth remains had long been known in Asia before they became known to Europeans. The origin of these remains was long a matter of debate and often explained as being remains of legendary creatures. The mammoth was identified as an extinct species of elephant by Georges Cuvier in 1796.

Floppy trunk syndrome is a condition that causes trunk paralysis in African bush elephants. Initially observed in 1989, the syndrome primarily affected bull elephants in several select regions in Zimbabwe. Afflicted elephants exhibit paralysis in their trunk, often having to adapt to feed. The loss of their trunks' prehensile abilities results in malnutrition and possibly death. The condition is a result of degeneration of nerves in the trunk, and is suggested to be a result of either heavy metals or toxins. There is debate over whether the condition is reversible.

<i>Loxodonta atlantica</i> Extinct species of mammal

Loxodonta atlantica is an extinct African species of elephant in the genus Loxodonta. It was larger than modern African elephants, with more progressive dentition. It includes Pleistocene fossils from Ternifine, Algeria, Middle Pleistocene fossils from Elandsfontein, South Africa and Late Pliocene fossils from the Omo River, Ethiopia. It is suggested to have an extinction date of around 400,000 years ago, during the Middle Pleistocene. L. atlantica has been suggested to have probably derived from L. adaurora; or L. exoptata. It is likely ancestral to the living African bush elephant, L. africana, with which it coexisted during the Middle Pleistocene prior to its extinction. The species is divided into two subspecies: L. atlantica atlantica and L. atlantica zulu. The type for Loxodonta atlantica is housed in the Muséum national d'histoire naturelle in Paris, but is listed without a specimen number.

<span class="mw-page-title-main">Knysna elephants</span> Group of African bush elephants

The Knysna elephants were the relicts of once substantial herds of African bush elephant in the Outeniqua/Tsitsikamma region of southernmost South Africa. As of 2022, the herds have been reduced to a lone adult female. The elephant herds roamed the southern tip of Africa into the 19th century and the 20th century, when contact with European farmers and hunters led to their decimation. It is conjectured that about 1,000 elephants historically roamed the Outeniqua/Tsitsikamma area. A 2006 DNA analysis of dung samples revealed the presence of at least 5 cows and possibly some bulls and calves, moving within an area of 121,000 hectares of forest managed by SANParks – the only unfenced elephant group in South Africa. However, by 2019, researchers realised that a mature female at the Knysna Forest was the last to survive.

Joyce Hatheway Poole is a biologist, ethologist, conservationist, and co-founder/scientific director of ElephantVoices. She is a world authority on elephant reproductive, communicative, and cognitive behavior.

<span class="mw-page-title-main">Elephant communication</span> Communication between elephants

Elephants communicate via touching, visual displays, vocalisations, seismic vibrations, and semiochemicals.

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