The World Wildlife Fund warned that although South Africa had managed to bring down rhino deaths due to poaching by 25 percent in 2018, the animals were still endangered and the crisis engulfing them was far from over.
Figures released via South Africa's Department of Environmental Affairs, as cited by the WWF in a statement, showed 769 rhinos were killed last year compared to 1,028 in 2017.
"The fact that fewer rhinos have been lost in South Africa in 2018 is good news and merits credit for the hard work and commitment of all those involved," doctor Jo Shaw, African Rhino Lead for WWF International, said in a statement.
"In spite of lower poaching numbers for 2018, the crisis for rhinos is far from over and it is important to consider the number of live rhinos remaining as well as the number of poaching losses," the WWF report said.
It was the first time in five years that the number of rhinos killed had dropped below 1,000.
Kruger National Park in the northeast is one of South Africa's main natural reserves, and it is home to the majority of the country's rhino population.
Fewer rhinos were killed in the park last year than the previous year - 421 in 2018 versus 504 in 2017 - but it was still the area where most of the killings happened.
The WWF said 229 alleged poachers were arrested last year in or near the park, 40 more suspects on the previous year.
Kruger was also the scene of 71 elephant killings at the hands of poachers in 2018, according to the organization.
The country has a population of about 5,000-5,400 black rhinos, which the WWF lists as "critically endangered," and between 19,600-21,000 white rhinos, listed as "near threatened."
"The overall status of our rhino populations remains a concern and we need continued commitment to address the systemic challenges for rhinos across the region," said Shaw.
South Africa has been fighting a serious escalation of poaching since 2008.
Poachers hunt the animals for their horns, which are then sold mostly on Asian markets.
Rhino horns are used in traditional Chinese medicine where they are mistakenly believed to have aphrodisiac and healing properties.
"Whilst 2018 saw some major arrests and successful convictions, the frequent granting of bail, especially to those in the crime syndicates co-ordinating rhino horn trafficking, is a serious concern," WWF warned.
"We need targeted efforts to address corruption and more effective international collaboration on investigations into syndicates operating in Asia to address the entire criminal supply chain," it added.