And elephant populations have also gone up, thanks to a blitz on illegal ivory hunters, the president’s office said.
It was not immediately possible to explain the discrepancy between the estimates from Tanzania’s government and Cites, the group that aims to ensure trade in animals and plants does not threaten their survival.
President John Magufuli spoke out against wildlife crime when he took office in 2015, urging security forces to arrest all those involved trafficking.
Within months, four Chinese men arrested at the Malawi border for smuggling rhino horns were jailed for 20 years.
“As a result of the work of a special taskforce launched in 2016 to fight wildlife poaching, elephant populations have increased from 43,330 in 2014 to over 60,000 presently,” officials said.
Elephant numbers in Tanzania plummeted by 60 per cent between 2009 to 2014, from 110,000 to just over 43,000, a 2015 census showed.
Conservation groups blamed rampant poaching, with much of the slaughter happening around the extensive Selous game reserve and the adjacent Mikumi National Park.
In one park, Ruaha, half the elephants – more than 4,000 – were killed by poachers in 2015 alone, research found.
Mark Jones, head of policy at wildlife charity the Born Free Foundation, said both rhinos and elephants breed slowly so attributed any population increases to other factors.
“This sounds like very good news but we should view these figures with caution until there’s independent verification – there’s no way that has occurred through breeding and protection alone,” he said.
It’s estimated there are just 415,000 elephants across Africa, down from 10m 90 years ago.
Demand for ivory has mostly come from China and Vietnam, where it is turned into jewels and ornaments. Research has found some buyers believed tusks and horns grew back.
Tanzania’s claim was published as wildlife investigators worldwide revealed thousands of species had been seized in a major crackdown at borders last month.
UK teams seized two bear skulls and skins, and four products derived from crocodiles, 10 tanned skins, and four ivory products including binoculars.