A quarter of all mammals and 13 % of bird species are heading towards a similar fate . Latest estimate of threats to animal and plant species published by international conservation group . Nearly 20,000 species now face threat of extinction including 40 % of fish and 33 % of reef building species . Report is ` ` clarion call to world leaders gathering in Rio , '' says WWF director general Philippe Marton - Lefevre . WWF director general warns Rio ` ` doomed to ridicule '' if world leaders do n't act decisively .
Latest estimate of threats to animal and plant species published by international conservation group . Nearly 20,000 species now face threat of extinction including 40 % of fish and 33 % of reef building species . Report is ` ` clarion call to world leaders gathering in Rio , '' says WWF director general Philippe Marton - Lefevre . WWF director general warns Rio ` ` doomed to ridicule '' if world leaders do n't act decisively .