Mainly Humans, who kill them for the bushmeat trade and also destroy habitat.
Chimps also make regular hunts on Black colobus monkies using advanced hunting tactics. The males will make the kill, but females will receive some as meat is often traded for both immediate and increased chance of future sexual allowances.
Also snakes, and other large predators i guess.
King colobus was created in 1780.
Olive colobus was created in 1838.
Angola colobus was created in 1860.
Black colobus was created in 1838.
Pennant's colobus was created in 1838.
Ursine colobus was created in 1834.
Colobus monkeys eat leaves, branches, and bamboo.
The Colobus monkey has an intermembral index in the 50-105 range. I've seen a couple of sources stating the number is in the high 70s. Also: Kikuyu is not the most common name of the colobus monkey (Colobus guereza). It is more commonly referred to as the black and white colobus or abyssinian colobus.
Colobus monkeys eat leaves, branches, and bamboo.
Black and White Colobus live in Kenya.
Western red colobus was created in 1792.
Udzungwa red colobus was created in 1900.