The president of Congo-Brazzaville has set fire to nearly five tonnes of seized elephant ivory at a summit to draw up the first pan-African strategy on wildlife poaching.

Denis Sassou Nguesso held out a long flaming torch to set ablaze the tusks, fuelled by captured illegal timber, then stepped back quickly from the sudden rush of heat. Accompanied by Idriss Déby, the president of Chad, he stood and applauded amid a throng of officials and camera crew.

Organisers of the illegal wildlife trade conference in the capital, Brazzaville, hope the ceremony will send a clear message. “Symbolism matters in these things,” said Anthony Kwaku Ohemeng-Boamah, country representative of the UN Development Programme. “It shows this is something the world community abhors. Burning is how most Asian societies dispose of dead bodies. We are disposing of the elephants that have been poached and we wish they were alive.”

Facebook Twitter Pinterest Thai customs officials display seized ivory in Bangkok. Photograph: Xinhua/Corbis

The trade has earned comparisons with drugs, arms and human trafficking as a global crime worth an estimated $23bn (£15bn) a year. Poachers in Africa are using cyanide, night-vision goggles and AK-47 rifles to keep up with demand in Thailand and China, where one elephant’s ivory can fetch $18,000. About 20,000 elephants were killed in 2013.

Ohemeng-Boamah said: “A conference of this nature, where all Africa comes together, is very important because animals know no boundaries. It’s like air pollution: when the wind blows, you don’t know where it will take you. There is an awareness in Africa that we need to do something. If we do not have equal strength jurisdictions, no one can say, ‘I’m saving elephants’.”

Déby told the summit that whereas Chad boasted 50,000 elephants half a century ago, its current population was just 1,500. “Poaching has gone beyond national borders and is part of an international mafia trade,” he said. “Chad is completely committed to the fight against the scourge, not only in Africa but at the international level and the world.”

Facebook Twitter Pinterest Déby sets alight tusks during a ceremony at Zakouma national park last year. Photograph: AFP/Getty

Celebrities including Prince William, David Beckham, a footballer, and Jackie Chan, an actor, have been involved in campaigns to raise public awareness. But while the international community has been ringing alarm bells, Africa has been accused of complacency and taking its abundance of natural wonders for granted.

Some of its 54 countries are said to be dragging their feet in dealing with the complex transnational trade despite pressure from the UK, organiser of a big conference in London last year, and other global partners. The African Union-backed conference in Brazzaville is pursuing an action plan that will dismantle mafia networks and show the continent speaking with one voice.

Philip Muruthi, senior director of conservation science at the African Wildlife Foundation, said: “Africans have to be angrier. You cannot make change if you have the status quo: ‘Elephants are dying, so what?’ Other people are saying there’s a crisis but we have to care. A lot of Africans think there is a lot of wildlife. Why? They’ve seen it at some point in their lives. An elephant goes into your garden and you think there are lots of elephants.”

Quick and concerted action is vital, he said. “In the area of corruption, kingpins not being prosecuted, we need to escalate the level of seriousness. That’s where collaborations are very important. Everybody says this is a serious crime like money laundering, governments are saying that, so what action is being taken? We should be seeing more people arrested, convicted and given deterrent punishments, but we are not.”

Facebook Twitter Pinterest One of the dwindling population of African giraffe, in Kouré, Niger. Photograph: Godong/Robert Harding World Imagery/Getty Images

Certain subspecies in Africa are near breaking point, Muruthi noted. The west African giraffe, found in Niger, is down to fewer than 500, and all types of the species are in decline. Fewer than 7,000 wild dogs remain, while the population of Grévy’s zebra is below 3,000. There are only five northern white rhino left on the planet.

“Unfortunately the number of species moving to vulnerable and endangered to critically endangered is on the increase. The rapid level of killing not only endangers the species but also several roles it plays in the ecosystem.”

Facebook Twitter Pinterest Game rangers free a female eland antelope from an illegal snare at Ol Pejeta Conservancy in Kenya. Photograph: Tony Karumba/AFP/Getty Images

Loss of elephants, for example, also damages trees whose seeds must pass through an elephant’s gut for germination, while a decline in predators such as lions has a “cascade effect” that can lead to overpopulation and overgrazing. The wildlife trafficking crisis is combined with a crisis of habitat loss, he added, as well as eroding livelihoods for millions of people in Africa.

Muruthi said: “I’m hoping for an action plan from this conference. It will be a folly if we just end up with a list of recommendations. These meetings are useful in that they keep awareness up but they can’t only do that.”

Some African states have been criticised for a lack of political will. The Republic of the Congo, Mozambique, South Africa and Tanzania are among those being urged to invest more resources, hire more park rangers and toughen legislation and sentences.

Congo-Brazzaville follows Kenya and Ethiopia which last month incinerated stockpiles of ivory to show their opposition to the trade. Henri Djambo, Congo-Brazzaville’s forest economy and sustainable development minister, said: “The main message is that you have to destroy the objects of shame.”

Poaching reduced the number of elephants here to 10,000 in the 1980s, but it has since recovered to 40,000, Djambo said, though strains on natural habitat mean the animals encroach on villages. “Our population has gained some ecological awareness that they’re not supposed to be killing the animals. But poaching is carried out by those with no sense of civil responsibility for personal gain.”

Facebook Twitter Pinterest A Kenyan wildlife official watches as a 15-tonne pile of ivory burns. Photograph: AFP/Getty

Estimates show a decline of 62% in forest – as opposed to savanna – elephants in the central African region encompassing Congo-Brazzaville, the neighbouring Democratic Republic of the Congo, the Central African Republic and Gabon between 2002 and 2012.

Djambo, 63, is also a novelist and playwright whose works often contain an ecological message. One of his plays, about children taking on the roles of game ranger, customs official and police officer to combat wildlife crime, was staged at the conference. “I start from the observation that people don’t read very much in this country. This is a country of oral traditions so I think this is the best way of communicating with the people.

“African political will and determination are key for the continent to be able to realise this massive undertaking. Everybody who’s concerned with an issue has to run in your direction when you’re calling them. Anybody [who] turns their back on the burning edifice of African biodiversity is someone who refuses to participate in extinguishing the fire.”

A document and a draft action plan from the conference will be taken to an African Union summit to be held in South Africa in June. Ibrahim Thiaw, assistant secretary general of the UN, told delegatesthe meeting could be an “epoch-making stage in the management of natural resources in Africa”.