The last male Sumatran rhinoceros in Malaysia has died, as conservationists warn the news should be a "wake-up call" to protect wildlife.

The critically-endangered Sumatran rhino, which is the smallest species of rhinoceros, was declared extinct in the wild in Malaysia in 2015.

Experts estimate only 30 to 80 Sumatran rhinos are left in the world, with many on the Indonesian island of Sumatra and the Indonesian side of Borneo.

Tam the rhino, who was about 30 years old, had been living at a wildlife reserve on Borneo island since being found wandering on a palm oil plantation in 2008.

The Borneo Rhino Alliance announced his death on Monday, saying: "It is with heavy hearts that we share the tragic news that Tam, Malaysia's last male Sumatran rhino, has passed away.


Image: Only 30 to 80 Sumatran rhinos are left in the wild, estimates say

"We will share more details in due time, but right now we need some time to mourn his passing."

Local media reported he had been suffering from kidney and liver problems for some time.

A female Sumatran rhino named Iman, who was captured in 2014, is now the only surviving member of the species left in Malaysia.

Puntung, another female rhino kept at the reserve, died of cancer in 2017.

WWF Malaysia paid tribute to Tam on Twitter, writing: "Today, we bid farewell to Tam, our last surviving male Sumatran #rhino.

"Our hearts are filled with sadness as we mourn the loss of a species. With Tam gone, we now only have Iman left, our last female rhino.

"Let the loss of Tam be the wakeup call. Our #wildlife needs protection."

Today, we bid farewell to Tam, our last surviving male Sumatran #rhino. Our hearts are filled with sadness as we mourn the loss of a species. With Tam gone, we now only have Iman left, our last female rhino. Let the loss of Tam be the wakeup call. Our #wildlife needs protection pic.twitter.com/3E6LbY5EzN — WWF-Malaysia (@WWFMy) May 27, 2019

The Sumatran rhino could be extinct within decades, according to conservation group International Rhino Foundation.

The subspecies is often isolated due to habitat loss and poaching, meaning they rarely breed.

Malaysia has been attempting to breed the rhinos in captivity using IVF, but has not been successful.

Tam's genetic material has been preserved for future attempts to reproduce the species, and an official told MSN News that Indonesia's government will resume talks on using advanced reproductive technology to try breeding Malaysia's last remaining female rhinoceros.