The forest elephant population within a supposed "sanctuary" in Central Africa declined by more than 80 percent over a decade's time due to poaching, new research finds.

The loss, representing about 25,000 elephant deaths, highlights how sanctuaries — while necessary to separate defined wilderness regions from more populated areas — can also increase threats to certain animals, since their populations then become so concentrated in particular areas.

In this case, documented in the journal Current Biology, the killings occurred at Gabon's Minkébé National Park, one of Central Africa's largest and most important preserves.

"Across Central Africa, forest elephant populations are being more and more restricted to protected areas, and so these will be the areas targeted by poachers," lead author John Poulson told Seeker.

Poulson, an assistant professor of tropical ecology at Duke University's Nicholas School of the Environment, and his colleagues had to overcome challenges in attempting to estimate numbers of the forest elephants in the park. He explained that most other elephants live in savanna regions, where aerial surveys can be used to accurately count elephants.

In forests, however, researchers must depend upon field teams walking over long distances to count elephant dung piles. Densities of poop piles are then converted to densities of elephants, with great care needed to factor in weather effects, such as the fact that greater rainfall can lead to faster decay of the elephant waste.

Using this method, the scientists determined that the population of forest elephants in the central and northern parts of the park between 2004 and 2014 was basically erased. Losses also occurred over the same period in the southern part of the park, but were not as substantial.

Photo: A lone forest elephant in Gabon's Minkébé National Park. Credit: John Poulson, Duke University

Numerous eyewitness accounts and the still-flourishing ivory trade offer evidence that poachers killed the forest elephants. Poulson said that Cameroon's national road, which runs very close to the central and northern parts of the park, makes it fairly easy for Cameroonese poachers to access the park and transport their illegal haul back to their nation's largest city, Douala, which is a major hub of the international ivory trade.

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Largely because of reports of poaching in Minkébé National Park, the Gabon government raised the status of forest elephants to "fully protected" in 2011, Pouson said. That same year, the federal authorities doubled the budget of the country's Parks Agency, growing its protection staff by 300 people.

They also created the National Park Police, posting 100 military personnel permanently in Minkébé to shore up protection of the park and to attempt to quell the extermination of elephants. In 2012, Gabon became the first Central African country to burn its entire ivory stock.

Poulson said, "While these efforts are admirable and necessary, by themselves they didn't stop poaching in the area, as evidenced by continued poaching of elephants in recent years."

Guards are posted along the Cameroon-Gabon border and other important entry points, but Poulson said, "The problem is that the area is very large, and poachers will always find a way to slip through if the stakes are high enough."

Poachers obviously have not forgotten the elephants and their ivory, but Poulson and others use the word "forgotten" to describe forest elephants due to both the ongoing threats to the pachyderm's populations and the elephant's status within the conservation community. It is estimated that 100,000 forest elephants live in Gabon now.

Poulson primarily believes forest elephants are forgotten "because of the failure of the international community to recognize the forest elephant as a distinct species. Currently, IUCN (International Union for Conservation of Nature) and CITES (Convention on the International Trade in Endangered Species) only recognize the African elephant, which includes the forest and savanna subspecies, and which is listed as 'vulnerable.'"

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The argument for recognizing forest elephants as a distinct species lies in the fact that the genetic differences separating these elephants from African savanna elephants is comparable in magnitude to the differences between modern Asian elephants and the extinct mammoths.

Photo: Young forest elephant in Gabon. Credit: Nathan Williamson for Gabon National Parks

Forest elephants do not become pregnant for the first time until they are 23 years of age, and they produce only one calf every five to six years. Savanna elephants, on the other hand, begin breeding at around 12 years of age and typically produce young at three to four year intervals. Forest elephants also tend to be much smaller, in terms of both stature and weight, than savanna elephants.

Politics could help to explain why forest elephants are "forgotten" and have not been recognized as a unique species.

"There is concern that two different species have not been recognized because that would reduce the estimated population of savanna elephants, and trade of its ivory would no longer be permitted," Poulson said. "This could result in 3 southern African nationals pulling out of CITES because they want to sell their ivory stocks."

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In addition to calling for distinct species recognition of the forest elephant, Poulson calls for the creation of new multinational protected areas and coordinated international law enforcement both to better protect the existing forest elephants and to ensure the prosecution of foreign nationals who commit, or encourage, wildlife crimes in other countries.

He hopes that the multinational Elephant Protection Initiative, of which Gabon is a founding member, will grow and strengthen, such that all elephant range states will adhere to it. The initiative works towards closing domestic ivory markets and putting stockpiles beyond economic use, such as by burning or otherwise taking ivory out of the marketplace.

"African-wide and national action plans must be implemented," Poulson said, "while there are still elephants left to manage."