which seem to have some sort of cardiovascular health benefit for western lowland gorillas, and are a known part of the natural diets for many wild populations. A study published in 2007 announced the discovery of this species fighting back against possible threats from humans. They "found several instances of gorillas throwing sticks and clumps of grass". This is unusual, because western lowland gorillas usually flee and rarely charge when they encounter humans. One mirror test in Gabon shows that western lowland gorilla silverbacks react aggressively when faced with a mirror, although refusing to look fully at their reflection. Conservation status The World Conservation Union lists the western gorilla as critically endangered, the most severe denomination next to global extinction, on its 2007 Red List of Threatened Species. The Ebola virus might be depleting western gorilla populations to a point where their recovery might become impossible, and the virus reduced populations in protected areas by 33% from 1992 to 2007, which may be equal to a decline of 45% for a period of just 20 years spanning 1992 to 2011. Poaching, commercial logging and civil wars in the countries that compose the western gorillas' habitat are also threats. Furthermore, reproductive rates are very low, with a maximum intrinsic rate of increase of about 3% and the high levels of decline from hunting and disease-induced mortality have caused declines in population of more than 60% over the last 20 to 25 years. Rather, under the optimistic estimate scenarios, population recovery would require almost 75 years. Yet within the next thirty years, habitat loss and degradation from agriculture, timber extraction, mining and climate change will become increasingly larger threats. Thus, a population reduction of more than 80% over three generations (i.e., 66 years from 1980 to 2046) seems likely. In the 1980s, a census taken of the gorilla populations in equatorial Africa was thought to be 100,000. Researchers adjusted the figure in 2008 after years of poaching and deforestation had reduced the population to approximately 50,000. Surveys conducted by the Wildlife Conservation Society in 2006 and 2007 found around 125,000 previously unreported gorillas have been living in the swamp forests of Lake Tele Community Reserve and in neighbouring Marantaceae (dryland) forests in the Republic of the Congo. This discovery could more than double the known population of the animals, though the effect that the discovery will have on the gorillas' conservation status