Duikers are split into two groups based on their habitat - forest and bush duikers. All forest species inhabit the rainforests of sub-Saharan Africa]], while the only known bush duiker, grey common duiker occupies savannas. Duikers are very shy, elusive creatures with a fondness for dense cover those that tend to live in more open areas, for example, are quick to disappear into thickets for protection. Because of their rarity and interspersed population, not much is known about duikers thus, further generalizations are widely based on the most commonly studied red forest, blue, yellow-backed, and common grey duiker. In tropical rainforest zones of Africa, people nonselectively hunt duikers for their hide, meat, and horns at highly unsustainable rates. Population trends for all species of duikers, excluding the common duiker and the smallest blue duiker, are significantly decreasing Aders' and particularly the larger duiker species such as the Jentink's and Abbott's duikers, are now considered endangered by the IUCN Red List of Threatened Species .