Tightened restrictions on the ivory trade have led to an increase in the trade in hippopotamus teeth, wildlife campaigners warn, with potentially dire consequences for a species already listed as “vulnerable to extinction”.
When the UK announced a near-total ban on elephant ivory trade last June, an animal welfare charity studied what was happening on three widely used online marketplaces.
“We detected the increase in the hippopotamus ivory trade in the UK within a month of the near-total ban on elephant ivory being introduced,” said Frankie Osuch, lead author of a report released in September by Born Free.
This was “deeply concerning evidence of an increased demand for hippopotamus ivory, whose numbers are endangered in the wild,” the report said.
Researchers say this pattern was evident as far back as 1989, when a global ban on the ivory trade was first agreed.
Like ivory, hippopotamus teeth and tusks are often used for decorative carvings, but they are cheaper and easier to obtain.
Hippopotamus body parts can still be traded under the Convention on International Trade in Endangered Species (CITES), although an export license is required for all international sales.
It has been calculated that between 1975, when CITES records began, and 2017, 770,000 kg of hippopotamus teeth were legally traded. But there is also illegal trade.
In 2020, hippopotamus teeth were among the most commonly seized mammal body parts in the EU, according to a report by the European Commission.
“There are more and more cases of sniffer dogs detecting hippopotamus teeth at various airports in Africa these days, and the detection doesn’t mean they’ve all been caught, maybe just half,” said Philip Muruthy, vice president of Africa Wildlife Funding.
A 2016 study by the International Union for Conservation of Nature (IUCN) estimated that the global population of the common hippopotamus was between 115,000 and 130,000 – a 30% decline since 1994.
Ten countries in West and Central Africa say numbers have plummeted due to poaching and land degradation.
They proposed a blanket trade ban last month ahead of a CITES meeting in Panama, but under CITES rules this would only have been possible if the population had declined by more than 50% in the last 10 years, and an IUCN analysis did not support this conclusion.
The 10 West and Central African countries then proposed an action called “annotation” that would have resulted in a zero quota for wild specimens traded for commercial purposes. But this proposal was not backed by the EU or by Eastern and Southern African countries, which say hippopotamus populations remain at healthy levels.
Some of the Eastern and Southern African countries – Tanzania, Uganda, Zambia and Zimbabwe – are also the source of three quarters of the estimated 13,909 hippos whose parts and products were traded between 2009 and 2018.
Joanna Swabe, senior director of public affairs at Humane Society International, points out that little work has been done since 2016 to establish hippopotamus numbers.
“Very little scientific research has been done on the actual hippopotamus population in any of these countries,” she says. “At the same time, different countries know what happens to their hippos within their territory, so they should not be ignored.”
Hippopotamuses have a low birth rate, producing only one offspring every two years, so a reduction in population size could have a long-term effect.
All hippos live in Africa – there are two species, the common hippopotamus (population estimated at 115,000 to 130,000 in 2016) and the pygmy hippopotamus (2,000-3,000)
The common hippopotamus was classified as “Vulnerable to Extinction” in 2016 on the International Union for Conservation of Nature (IUCN) Red List.
The parts and products of an estimated 13,909 hippos were legally traded between 2009 and 2018 – three-quarters of these came from Tanzania, Uganda, Zambia and Zimbabwe
Between 1975 and 2017, 770,000 kg of hippopotamus teeth were legally traded – the extent of the illegal trade is unknown
Wildlife experts also say the legal and illegal trade in hippopotamus teeth should be closely monitored.
The common hippopotamus is listed on Appendix II of CITES, meaning it could be threatened with extinction unless trade is tightly controlled.
The 10 countries pushing for a global ban on commercial paper claim there is strong evidence of the “mixing of legal and illegal hippopotamus ivory”, suggesting that poached ivory is “laundered in the legal market”.
Without tighter controls, campaigners warn, hippos could share the fate of elephants, which are endangered — or critically endangered in the case of the African bush elephant — because so many have been killed by poachers for their tusks.