The founder of an animal conservation NGO, who received numerous death threats for battling international ivory-trafficking, has been killed in Tanzania.

Wayne Lotter, 51, was shot as he rode in a taxi from Dar as Salaam Airport to a hotel.

Police said the car was stopped by another vehicle on Wednesday evening (16 August). Two men, one armed, then opened his car door and shot him. An investigation has been launched.

The South African was co-founder of the PAMS Foundation, an NGO that aims to protect elephants and giraffes by providing anti-poaching support to communities and governments in Africa.

Lotter, who had worked in conservation for nearly three decades, had received numerous death threats since he started the foundation in 2009.

His organisation finances Tanzania's National and Transnational Serious Crimes Investigation Unit, which has arrested some 2,000 poachers and ivory traffickers and boasts an 80% conviction rate since 2012.

The unit's scalps include the 2015 arrests of Boniface Matthew Maliango and "ivory queen" Yang Feng Glan, two of the country's most notorious poaching and ivory trading kingpins.

"Wayne devoted his life to Africa's wildlife. From working as a ranger in his native South Africa as a young man to leading the charge against poaching in Tanzania," said the PAMS Foundation.

"He died bravely fighting for the cause he was most passionate about."

However, poaching, habitat loss and a growing human population have had a catastrophic impact on wildlife across Africa in recent years, driving several species to the brink of extinction.

A census last year found that Africa's elephant population had plummeted by 30% between 2007 and 2014, leaving just 352,271 animals across 93% of their range.

Tanzania has been cited as the centre of this catastrophic decline, losing some 60% of all its elephants in just five years.

In 2014 the United Nations put the Selous game reserve, in southern Tanzania, on its list of world heritage sites in danger, because of rampant poaching.

Lotter leaves behind his wife Inge and two daughters, Cara Jayne and Tamsin.