African forest elephants are not the slowest breeding animals in the world; that accolade, unfortunately, goes to the orangutan. But with female forest elephants only reaching sexual maturity after two decades and a slow reproduction rate of giving birth just once every five years, they are definitely on the high end of that list.
Exacerbated by the intense level of poaching they have suffered in the last 15 years, these elusive and shy creatures could be facing extinction a lot sooner than expected as population levels have dropped by more than 60 percent since 2002, according to the first-ever study on forest elephant demographics, published in the Journal of Applied Ecology.
Researchers from the Wildlife Conservation Society (WCS), Cornell Lab of Ornithology’s Elephant Listening Project, Colorado State University, and Save the Elephants studied data collected by lead author Andrea Turkalo of WCS between 1990 and 2013 from the Dzanga Bai in Sangha Trinational, a World Heritage-listed forest in the Congo Basin.
It had been previously assumed that forest elephants, a subspecies of African elephants, gave birth at rates similar to savanna elephants, but Turkalo’s team discovered that it takes more than 20 years for females to start reproducing and that the average time period between births was five to six years, meaning population growth is actually three times slower than their savanna counterparts.
This isn’t good news when statistical data from the study shows that forest elephants are experiencing the greatest levels of poaching in Africa, with a 62 percent population decrease between 2002 and 2011 and a 30 percent loss of their geographical range, giving an estimated loss of between 10 and 18 percent of their population every year – all of which makes them “significantly more sensitive to human-induced mortality than their congeneric species.”
“The impact of these data is that forest elephants are facing a huge challenge in recovery from current poaching rates and if the poaching is not curtailed they are faced with extinction sooner than we thought," said Turkalo in a statement. "Unless we can better protect them and curtail the development of extractive industries in areas where forest elephants are present, these animals are condemned.”
The authors suggest that “debates regarding the sustainability of the ivory trade for the species appear to have overestimated growth rates of forest elephants.” According to their findings, this slow reproduction rate means it could take at least 90 years for the species to recover from their rapid population decline.
The paper concludes: “Such slow intrinsic growth challenges current perceptions of historic and contemporary ivory trade impacts on forest elephants, highlighting the urgent need to stem poaching and institute long-term protective measures.”
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