過去50年間，象牙盜獵和棲地喪失帶給非洲象沉重的生存壓力。世界自然保育聯盟受脅物種紅皮書，現把非洲森林象列為極度瀕危級（Critically Endangered, CR），非洲莽原象列為瀕危級（Endangered, EN）。
在此次更新前，非洲象被視為單一物種，受脅等級屬於易危級（Vulnerable, VU）。由於新的遺傳證據出現，世界自然保育聯盟（International Union for Conservation of Nature, IUCN）受脅物種紅皮書首次對這兩個物種分別進行評估。
專家們根據最新大象族群遺傳學研究後，決定將非洲森林象（African Forest Elephant，學名：Loxodonta cyclotis）和非洲莽原象（African Savanna Elephant，學名：Loxodonta africana）視為兩個單獨的物種。還有第三種物種亞洲象，但此次評估未包含在內。
IUCN物種存續委員會主席羅德里格（Jon Paul Rodríguez）博士說，這樣的評估結果，有助將保育重點放在瀕危非洲森林象和非洲莽原象上。
《保護野生動物遷徙物種公約（Conservation of Migratory Species of Wild Animals）》執行秘書弗蘭克爾（Amy Fraenkel）說，「非洲森林象和非洲莽原象，現已在公約附錄二列為兩個不同物種。」
部分非洲莽原象族群的個體數量已保持穩定或成長了數十年，尤其是在卡萬戈－贊比西邊疆保護區（Kavango-Zambezi Transfrontier Conservation Area），這裡有非洲大陸上最大的草原象亞族群。
Poaching for ivory and loss of habitat over the past five decades have taken a grim toll on African elephants. The African forest elephant, Loxodonta cyclotis, is now listed as Critically Endangered and the African savanna elephant, Loxodonta africana, is listed as Endangered on the authoritative Red List of Threatened Species compiled by the International Union for the Conservation of Nature, IUCN.
Before today’s update, African elephants were treated as a single species, listed as Vulnerable to extinction. This is the first time the two species have been assessed separately for the IUCN Red List, after the emergence of new genetic evidence.
The 2016 IUCN African Elephant Status Report provides the most recent reliable estimate of the continental population of the two species combined, at around 415,000 elephants.
The IUCN Red List now covers 134,425 species of which 37,480 are threatened with extinction.
Two Separate African Elephant Species Emerge
The decision to treat African forest and savanna elephants as two separate species is the result of the consensus that has emerged among experts following new research into the genetics of elephant populations. There is also a third species, the Asian elephant, which is not covered in this assessment.
Forest elephants occur in the tropical forests of Central Africa and in a range of habitats in West Africa. They rarely overlap with the range of the savanna elephant, which prefers open country and is found in a variety of habitats in Sub-Saharan Africa including grasslands and deserts.
Long considered to be a subspecies of the African elephant, the African forest elephant is now believed by many scientists to be a species separate from the African savanna or bush elephant. They are smaller than the better-known savanna elephant, have tusks that are straight and point downward, unlike the savanna elephants’ curved tusks.
The forest elephant, which has a more restricted natural distribution, is thought to occupy only a quarter of its historic range today, with the largest remaining populations found in Gabon and the Republic of the Congo.
Forest elephants have the slowest reproductive rate of the three elephant species, according to the Kenya-based nonprofit African Wildlife Foundation. “The sexually mature age of these elephants is not until 23 and then the average gestation period is about two years. In this case, any population decline caused by poaching, bushmeat trade, logging operations, and natural resource extraction is more devastating. If poaching was stopped today, then scientists say it would take 81 years to reverse the 62 percent decline experienced in the last decade.”
Dr. Jon Paul Rodríguez, who chairs the IUCN Species Survival Commission, said, “These two Red List assessments reflect the outcome of the IUCN SSC African Elephant Specialist Group taking a bold, collaborative, evidence-based decision to assess the African elephant as two separate species for the first time and understanding the implications and consequences of this shift.”
“The outcome is robust assessments that provide users with the options to focus conservation efforts appropriately for the Critically Endangered forest elephant and the Endangered savanna elephant,” he said.
“For these assessments, a team of six assessors used data from as far back as the 1960s and a fully data-driven modeling approach to consolidate the decades-long efforts of many survey teams for the first time,” said Dr. Kathleen Gobush, lead assessor of the African elephants and member of the IUCN Species Survival Commission African Elephant Specialist Group.
“The results quantify the dramatic extent of the decline of these ecologically important animals. With persistent demand for ivory and escalating human pressures on Africa’s wildlands, concern for Africa’s elephants is high, and the need to creatively conserve and wisely manage these animals and their habitats is more acute than ever,” Dr. Gobush said.
“The Forest Elephant and the Savannah Elephant are already listed as two separate species on Appendix II of the Convention on Migratory Species,” said Amy Fraenkel, executive secretary of the Convention on the Conservation of Migratory Species of Wild Animals. “We welcome IUCN’s recognition of two distinct African elephant species and hope that it will lead to greater conservation actions for both species. In particular, the Forest Elephant has suffered drastic declines over the past few decades.”
The latest assessments reveal a broad decline in African elephant numbers across the continent. The number of African forest elephants fell by more than 86 percent over a period of 31 years, while the population of African savanna elephants decreased by at least 60 percent over the last 50 years, according to the assessments.
Both species have declined since 2008 due to an increase in poaching, which peaked in 2011 but continues to threaten elephant populations. The ongoing conversion of their habitats to agricultural and other land uses is another threat.
Dr. Dave Balfour, an assessor of the African elephants and member of the IUCN Species Survival Commission African Elephant Specialist Group, said, “While the results of the assessment place the continental population of savanna elephants in the Endangered category, it is important to keep in mind that at a site level, some subpopulations are thriving. For this reason, considerable caution and local knowledge are required when translating these results into policy.”
These latest assessments do show the impact of successful conservation efforts despite the overall declining trend of both African elephant species. Anti-poaching measures on the ground, together with more supportive legislation and land use planning which seeks to foster human-wildlife coexistence, have been key to successful elephant conservation, the IUCN says.
As a result, some forest elephants have stabilized in well-managed conservation areas in Gabon and the Republic of the Congo.
Savanna elephant numbers have also been stable or growing for decades especially in the Kavango-Zambezi Transfrontier Conservation Area, which harbors the largest subpopulation of this species on the continent.