Estrus females tend to mate with multiple males, though sexual consortships can be formed. Female sooty and Tana River mangabeys have a postconception estrus, which may serve to confuse paternity, though a captive study showed sooty males to be able to tell the difference between a maximal fertile swelling and a postconception swelling. Mangabeys can live around 20-30 years, depending on the species. Humans and mangabeys can compete for the same wild food sources, and they are also hunted by humans for meat and killed as crop-raiding pests. Black mangabeys are also prey for the crowned hawk eagle.
Deforestation is also a continuing problem.
Agile mangabeys and Tana River mangabeys have very similar vocalizations. More is known about the sooty mangabey, a subspecies, than about the red-capped mangabey, the main species. Sooty mangabeys have powerful jaws that can be used to crack nuts that other monkeys cannot crack. Red-capped mangabeys are good swimmers. Sooty mangabeys are the only species of primate besides humans that can acquire leprosy from another member of their own species.