Sleeping site selection by golden-backed uacaris, Cacajao melanocephalus ouakary (Pitheciidae), in Amazonian flooded forests

Abstract

In Amazonian seasonally flooded forest (igapó), golden-backed uacaris, Cacajao melanocephalus ouakary, show high selectivity for sleeping trees. Of 89 tree species in igapó, only 16 were used for sleeping (18%). Hydrochorea marginata (Fabaceae) and Ormosia paraensis (Fabaceae) were used most frequently (41% of records) despite being uncommon (Ivlev electivity ratios were 0.76, and 0.84, respectively), though the third most commonly used species (11%), Amanoa oblongifolia (Euphorbiaceae), was selected at near parity. All three species have broad, open canopies with large horizontal limbs and uncluttered interiors. Compared with random trees, sleeping trees had above average diameter at breast height (DBH) and height, lacked lianas and wasp nests, and were more frequently within 5 m of open water. Uacaris generally slept one adult per tree or widely separated in the same canopy and on the outer third of the branch. These behaviours are interpreted as maximising detection of both aerial and arboreal predators.

Sleeping site and tree selection by Sichuan snub‐nosed monkeys (Rhinopithecus roxellana) in Baihe Nature Reserve, Sichuan, China

“…On a smaller spatial scale, the characteristics of sleeping trees are also important, particularly for arboreal primate species (von Hippel, ; Hankerson, Franklin, & Dietz, ). They have been shown to select different characteristics of sleeping trees to (1) make access more difficult for terrestrial predators, that is, tall emergent trees (Bitetti, Vidal, Baldovino, & Benesovsky, ; Cui, Tai, Lin, & Wen, ), higher first branches (Liu & Zhao, ; Li et al, ), and crowns without lianas (Barnett, Shaw, Spironello, MacLarnon, & Ross, ; Fei et al, ; Phoonjampa, Koenig, Borries, Gale, & Savini, ); (2) enhance their field of view to better monitor the surrounding environment, that is, less shrub cover (Hankerson et al, ), close proximity to riverbanks (Bernard, Matsuda, Hanya, & Ahmad, ; Thiry et al, ); (3) provide escape routes by utilizing arboreal connectivity between surrounding trees (Bernard et al, ; Fan & Jiang, ; Hankerson et al, ); (4) shelter from extreme climatic conditions in both tropical and temperate habitats, that is, utilizing dense canopies (Cui et al, ; Xiang, Nie, Chang, Wei, & Ming, ); palm trees and tree hollows (Heymann, ). Sleeping site and tree selection can also be influenced by other factors, for example, group size (Anderson, ; Bitetti et al, ) and to minimize parasitic infections (Feilen & Marshall, ).…”

Crying Tapir: The Functionality of Errors and Accuracy in Predator Recognition in Two Neotropical High-Canopy Primates

“…The mass of adult uacaris averages some 3 kg [Smith and Jungers, 1997]. Predation by eagles has been observed [Barnett et al, 2011], and predator avoidance appears to structure terrestrial foraging activity [Barnett et al, 2012a] and sleeping tree choice [Barnett et al, 2012b]. As with other pitheciines, uacaris are difficult to study, being timid and often requiring up to a year of contact before studies can be conducted [Pinto et al, 2013].…”

Terrestrial Foraging by Cacajao melanocephalus ouakary (Primates) in Amazonian Brazil: Is Choice of Seed Patch Size and Position Related to Predation Risk?

“…Data on terrestrial feeding were collected as part of a broader study of C. m. ouakary habitat and diet selection [Barnett et al, 2008[Barnett et al, , 2011[Barnett et al, , 2012Barnett, 2010], for which scan sampling was used to quantify diet choice and time budget, and ad libitum sampling was used to collect data on rare or previously unrecorded behaviours. Because terrestrial foraging (a) was not previously recorded for C. m. ouakary and (b) occurred in individual bouts that were always of short duration, all sampling relating to uacari behaviours on the ground were ad libitum.…”

“…As has long been appreciated [De Vore and Hall, 1965;Terborgh, 1983;van Schaik et al, 1983], avoiding predation touches nearly all aspects of primate life from foraging, vigilance, cover use and time spent grooming [Hart, 2007], to choice of sleeping trees [Barnett et al, 2012]. Indeed, it may well be one of the major activities structuring the rhythm and form of the primate day [Ferrari, 2009].…”