Leopard (Panthera pardus) predation on a red-tailed monkey (Cercopithecus ascanius) in the Issa Valley, western Tanzania

Abstract

Predation is predicted to be an important selection pressure for primates. Evidence for this hypothesis is rare, however, due to the scarcity of direct observations of primate predation. We describe an observation of leopard (Panthera pardus) predation on a red-tailed monkey (Cercopithecus ascanius schmidti) at the Issa Valley, a savanna-woodland mosaic landscape in western Tanzania. We compare rates of evidence of leopard presence between Issa and other primate study sites in sub-Saharan Africa. An increase in direct observations of leopards at Issa in recent years suggests that leopards may be habituating to researcher presence.

Leopard predation on gelada monkeys at Guassa, Ethiopia

“…If, as we suspect, concealment is important to a leopard's predatory success on geladas, then the microhabitat occupied by geladas should influence their risk of predation. Indeed, many primate species are known to increase vigilance rates in high‐risk areas or avoid these areas altogether (olive baboons: Matsumoto‐Oda, 2015; white‐faced capuchins, Cebus capucinus : Campos & Fedigan, 2014; patas monkeys: Burnham & Riordan, 2012; red‐tailed monkeys, Cercopithecus ascanius : McLester, Sweeney, Stewart, & Piel, 2019). Additional observations of gelada‐predator interactions are needed to evaluate whether geladas alter their vigilance behavior in high‐risk microhabitats or their ranging patterns after encounters with predators.…”

Cercopithecine and Colobine Abundance Across Protected and Unprotected Land in the Greater Mahale Ecosystem, Western Tanzania

“…In forests, primates are particularly vulnerable to land conversion that reduces tree cover, while in woodlands and grasslands, primates are more easily hunted or ensnared (Isaac and Cowlishaw 2004;Kümpel et al 2008). In heterogeneous environments, primates that utilize multiple vegetation types, e.g., red-tailed monkeys (McLester et al 2018;Tapper et al 2019), should therefore encounter a greater diversity of threats, which may exacerbate population decline.…”

Food abundance and weather influence habitat‐specific ranging patterns in forest‐ and savanna mosaic‐dwelling red‐tailed monkeys (Cercopithecus ascanius)

“…At Issa, however, forest configuration and a large home range mean that monkeys may not travel to distant patches if reducing DTD and increasing group spread are more efficient alternatives (Ganas & Robbins, ). Potential predators are frequently encountered by red‐tailed monkeys at both sites (e.g., chimpanzees; crowned‐hawk eagles, Mitani et al, ; Watts & Mitani, ; McLester et al, ). Anti‐predator responses include hiding or changing group travel direction (Cords, ), which affect time spent in an area.…”

“…The region is characterized by two distinct seasons: wet from November to April and dry (<100 mm monthly rainfall) from May to October (Piel et al, ; see Results). Chimpanzees also prey upon red‐tailed monkeys at Issa (C. Giuliano unpublished data), and possible predators include both crowned‐hawk eagles and five large carnivores: leopards ( Panthera pardus ), lions ( P. leo ), African wild dogs ( Lycaon pictus ), East Africa black‐backed jackal ( Canis mesomelas schmidti ), and spotted hyenas ( Crocuta crocuta ; McLester, Sweeney, Stewart, & Piel, ). We followed one habituated group at Issa: K0 included between one and four adult males at any one time and increased from about 35–55 total individuals during the study.…”