The first ever pan-African survey of savanna elephants has revealed that nearly one third, or at least 144,000 of the continent's largest elephants, have been wiped out between 2007 and 2014.
Over the past two years, Elephants Without Borders principal investigator Dr Mike Chase has been counting the animals from a light plane for the Great Elephant Census.
"We spent thousands of hours on transits flying over areas where elephants historically occurred, but are no longer present in these habitats. Some landscapes we saw more dead elephants than live elephants," said Dr Chase.
"I don't think anyone in the world has seen the number of dead elephants that I've seen over the last two years at the Great Elephant Census and for me, this becomes a lot more personal."
Of the 18 countries surveyed, the biggest drops in numbers were recorded in Angola, Mozambique and Tanzania.
Botswana, where Dr Chase is based, has more elephants than any other country in Africa, with a population of more than 130,000.
Elephants in Africa are in danger of being wiped out as ivory trades continue to drive poaching across the continent (AAP) Source: AAP
But he said elephants were under constant threat of poachers.
Since the early 2000s, the rise of the middle class in Asia has fueled demand for ivory products.
The black market wholesale price for ivory soared in China from $120 a kilo in 2002, to more than $2000 a kilo in 2014.
Environmentalist, Sir David Attenborough, told CNN the possible extinction of African elephants is unacceptable.
"Well I think it's a crime, and a crime that if it happens, will rest heavily on humanity's shoulders. What a dreadful thing to do. Appalling. And for what reason? For vanity, or for, I mean, people believe that ivory is magical in some kind of way.
"Well I can't argue about that, but it's not that magical that it justifies exterminating a wonderful, extraordinary animal like that," Sir Attenborough said.
He is one of many scientists who want the sale and possession of ivory to be outlawed around the globe.
"I think in the end it's going to have to come to it that they're going to become totally protected, and that the sale of ivory - certainly of ivory collected or no more than 100 years old - should be illegal.
"I don't see any way of getting round it."
Experts say if poaching is stopped, elephants might have a chance at regenerating populations.
An official inspects the stock during a tour of the country's ivory stockpile at the Zimbabwe National Parks Headquarters in Harare. (AAP) Source: AAP
Simon Hedges from the Wildlife Conservation Society told the BBC anti-poaching laws must be better enforced across borders.
"We need to refocus as a conservation community that the governments in those countries and the conservation partners ... provide effective law enforcement at the key sites and do as much as we can to (stop) trafficking ... ivory and the demand for ivory in East Asia," said Mr Hedges.
Botswana's response
In response to the poaching, more than 700 soldiers now guard Botswana's borders. Armed teams spend days on foot with a mandate to "shoot dead" poachers.
They are a highly organised groups of about 12 people, some with special forces training.
A way forward?
Despite the worrying findings, researchers said there were some signs of hope.
In a handful of countries, elephant populations were stable, with some slightly increasing.
Elephant herds were also found in Ethiopia and Kenya, in areas where local populations were thought to be extinct.
But satellite data showed that the animals were avoiding places where there was danger.
"You know elephants clearly have a cognitive ability to understand where they are threatened and where they are safe, and in this case, they are seeking refuge and sanctuary in Botswana - where they're well protected," Dr Chase said.
African savanna elephants graze in Serengeti National Park in Tanzania. (AAP) Source: AAO
The quest for a long-term plan
Speaking with the BBC, the Director of Wildlife and National Parks, Major General Tiroyamodimo said wildlife sanctuaries were now becoming crowded.
"Currently we are housing a lot refugee elephants in Botswana. Currently the biomass of elephants in Botswana is so high per square kilometer that it puts a lot of pressure on the environment."
Researchers said they hoped the data from the Great Elephant Census would help guide policy decisions aimed at better protecting elephants.
The findings come ahead of the International Union for the Conservation of Nature congress in Hawaii commencing this week, and the
It comes ahead of an International Conservation meeting in Hawaii, and the Trade in Endangered Species of Wild Fauna and Flora summit in South Africa, which is expected to be held in the coming weeks.
Key findings from the Great Elephant Census
- Savanna elephant populations declined by 30 per cent (equal to 144,000 elephants) between 2007 and 2014.
- The current rate of decline is 8 per cent per year, primarily due to poaching. The rate of decline accelerated from 2007 to 2014.
- 352,271 elephants were counted in the 18 countries surveyed. This figure represents at least 93 per cent of savanna elephants in these countries.
- 84 per cent of the population surveyed was sighted in legally protected areas while 16 per cent were in unprotected areas. However, high numbers of elephant carcasses were discovered in many protected areas, indicating that elephants are struggling both inside and outside parks.
