DECIMATION: African elephants decline by staggering 77% over 5 decades

A new study has analysed 53 years of elephant population survey data across Africa, concluding that habitat loss and poaching have driven dramatic declines in African elephants.

The study, titled 'Survey-based inference of continental African elephant decline', published in Proceedings of the National Academy of Sciences, noted it was challenging to measure elephant numbers and monitor changes across the entire continent.

According to the study, from 1964 to 2016, forest elephant populations decreased on average by 90%, while savanna elephant populations declined by 70%.

Overall, elephant populations in Africa declined by 77% on average.



Shining a light

Survey data from 475 sites in 37 countries were looked at, including Namibia, making it the most comprehensive assessment of African elephants to date.

Declines were not uniform across the continent, with some populations disappearing completely and others showing rapid growth.

Identifying success stories where elephant populations are stable or increasing could help with their conservation, the report stated.

"This paper shows the scale of the declines and how widespread they are across the continent," said Colorado State University Professor George Wittemyer, one of the architects of the study and chair of the scientific board of Save the Elephants. "It shines a light on how quickly even something as big and noticeable as elephants can just disappear."

The study found that surveys of savanna elephants were done by spotters in planes, and forest elephants were counted on foot patrols.



Varying degrees

The report said drones are not yet capable of the long flights over remote areas necessary to survey elephants, and processing drone imagery is also resource intensive.

It pointed out that Africa is more than three times the size of the United States, and each African country has its own wildlife management policies and political system in place. Some places survey regularly, and others not at all. Existing surveys were conducted through careful logistical planning and resource investment.

As elephant populations declined, some protected spaces were condensed and survey borders changed, the study noted.

The study authors looked at site-based trends to get a picture of the overall distribution of trends.

"It's not a metric of the number of elephants left on the continent," Wittemyer said. "It is an assessment of how each population is doing, and they're generally not doing great."



Decimated and thriving

The study examined how African elephants fared by species and region. In the war-torn Sahel region of northern Africa, elephant populations have been decimated, the survey found.

Eastern and central Africa generally saw declines from ivory poaching as well as from human population growth and wilderness conversion crowding out elephants.

However, elephants are thriving in parts of southern Africa, particularly in Botswana, where populations have been protected and sustainably managed.

The authors said the study's comprehensive assessment of the status of African elephants is fundamental to management decisions like knowing where to invest limited funding and capabilities to best protect elephants.

"The overall story is one of decline, but we are focusing on long-term stability of the species," Wittemyer said. "I think we can do that in a bunch of places, but not all places."

The co-authors of the study include Kathleen Gobush (University of Washington), Fiona Maisels (Wildlife Conservation Society and University of Stirling), Dave Balfour (Nelson Mandela University) and Russell Taylor (WWF Namibia).