Image caption The illegal trade in ivory has seen elephant numbers plummet

The world's biggest conference on species protection has opened in South Africa amid concern and division over the survival of elephants.

The Convention on the International Trade in Endangered Species (Cites) will address proposals impacting more than 500 plants and animals.

But elephants are likely to top the bill with countries bitterly divided over the best way to protect the ponderous pachyderms.

The meeting lasts until 5 October.

Poaching surge

Billed as the largest gathering in the 43-year history of the convention, the 17th Conference of the Parties (COP) will see more than 2,500 delegates from more than 180 countries come together in Johannesburg.

While there are proposals affecting lions, sharks, rhinos, pangolins and dozens of other species, the main focus will be on elephants.

There have been growing international concerns about the surge in poaching for ivory that has seen elephant numbers plummet by 30% in the past seven years.

And while Cites Secretariat has argued that there has been a slowdown in the trend, some new figures released at the meeting cast doubt on this view.

The Elephant Trade Information System (ETIS) is the world's most comprehensive database on the illicit trade in elephant products. It is managed by Traffic, the wildlife monitoring network, on behalf of Cites.

Speaking to BBC News, Dr Richard Thomas from Traffic said that new information presented at this meeting suggested that what appeared to be a downturn in illegal ivory activities in 2014 might have been a false dawn.

"The indications were that the 2014 figure, it looked like there was a drop, now the 2015 data has been put in there for ivory it is certainly at the level it was in 2012/13 and that's very disheartening," he said.

"We don't know what it means in terms of poaching but it's likely to be a fairly simple equation, with high levels of ivory meaning high levels of poaching."

Image caption Percentage change estimates are per year for 2010-2014, so total losses are three or four times the percentages indicated on the graphic

At this meeting there are a number of proposals reflecting very different approaches to the elephant problem.

Namibia and Zimbabwe are seeking to liberalise the restrictions that see them prevented from selling ivory, even though the elephants in their countries are categorised as Appendix II, a lower level of protection that normally allows countries to trade in a species or its parts.

However, a counter proposal from a number of other African countries seeks to raise all African elephants to Appendix I to ensure there is no legal loophole for any ivory trade.

Legacy issues

Several conservation groups are backing this tougher stand.

"There is no greater protection for imperilled species from detrimental trade than an Appendix I listing," said Iris Ho from Humane Society International.

"A continued split-listing of the African elephant is akin to a declaration by Cites to open the ivory trade for business. The conservation legacy of Cites is at stake, and so is the survival of the African elephant."

Image caption Loss of habitat has also affected elephant numbers

Many have also taken issue with the Cites Secretariat, who have advised countries meeting here to reject the up-listing of all African elephants to Appendix I, arguing that it might provoke some nations to opt out of Cites altogether and resume an unsupervised trade.

"The secretariat has over-stepped its powers in trying to influence policy before a proposal has even been discussed," said Robert Hepworth, a former chair of the Cites Standing Committee and now an adviser to the David Shepherd Wildlife Foundation.

There are other underlying factors that bring an added urgency to the discussions here on elephants.

Back in 2007 similar divisions on the issue of elephants ultimately forced a compromise at Cites, where a one-off sale of ivory was allowed in 2008 and all other proposals for sales were off limits until 2017.

"One of the parts of that deal in 2007 was that there would be a process devised, a mechanism would be established, to sell ivory and that hasn't happened," said Dr Thomas.

"The countries that signed up to it in the belief that they would be able to trade in the future, they don't want to see that part of the deal fall through."

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