Campaign group Mighty Earth says aerial drones, satellite imaging and field research show farmers carried out forest-burning for fast food giants soy suppliers
Jaguars, giant anteaters and sloths have all been affected by the disappearance of around 700,000 hectares (1,729,738 acres) of forest land between 2011 and 2015.
The campaign group Mighty Earth says that evidence gathered from aerial drones, satellite imaging, supply-chain mapping and field research shows a systematic pattern of forest-burning.
Local farmers carried out the forest-burning to grow soybeans for Burger Kings suppliers Cargill and Bunge, the only two agricultural traders known to be operating in the area.
Glenn Hurowitz, Mighty Earths CEO, said: The connections are quite clear. Bunge and Cargill supply Burger King and other big meat sellers with grain. McDonalds, Subway and KFC are not perfect but theyre doing a hell of a lot more to protect the forests. If Burger King does not respond immediately to people who want to know where their food comes from, then people should shop elsewhere.
The destruction of tropical forest and savannah land highlighted in the report is concentrated in Bolivias lowland forests and in the Brazilian Cerrado, where the pace of deforestation is now outstripping that of the Amazon.
One of Burger Kings suppliers buys soy from Bunge that originates in the Brazilian Cerrado, according to commodities data provided by the Stockholm Enterprise Institute.
Cargill has also sponsored Burger Kings annual convention in 2015, and donated a five-figure sum to the Burger King McLamore Foundation in 2014.
Last year, nearly 2m hectares of land was deforested in Brazil up from 1.5m in 2015 while an estimated 865,000 hectares of forest was cleared in Bolivia, compared to 667,000 a year in the 2000s.
Not all of the forest clearing was linked to soy production, but Mighty Earth says food companies are not doing enough to prevent deforestation in areas they operate in, and offer financial incentives that spur the process in the first place.
Burger King, which is owned by the Brazilian investment firm 3G Capital, does not disclose details of its suppliers but has refused to rule out buying products produced on deforested land.
Sharon Smith, a tropical forests manager at the Union of Concerned Scientists, said: Burger King is one of the worlds largest fast food companies, but consistently ranks last in the industry when it comes to environmental protection policies. The fast food giant needs to follow its competitors like McDonalds and demand that its suppliers are not destroying tropical forests as part of their business model.
The fast food giant, which operates at least one joint venture with Cargill, declined to respond to requests for comment.