Population organization of wild pig-tailed macaques (Macaca nemestrina nemestrina) in West Sumatra

Abstract

A field study on wild pig-tailed macaques was conducted in West Sumatra, Indonesia, during three periods from January 1985 to February 1987. During the nine months of the first two periods, unprovisioned monkeys were traced and observed. During the eight months of the last period, monkeys were provisioned and observed mainly at baiting sites. Three troops and ten solitary males appeared at the two baiting sites. Some males immigrated into and emigrated from the troops. The troops had a multi-male multi-female composition. The size of the various troops was 74, 49, and 81 individuals, respectively, and the mean adult sex ratio in the troops was 1:6.3; that is, markedly biased towards females. The home ranges of two of the troops overlapped considerably. When the troops encountered each other at the baiting sites, a clear dominance relationship was recognized.The troops differed in their integration as ranging units: two of the troops did not form subgroups (temporary fission and fusion of each troop), while the other troop frequently split into subgroups. Recent field studies on pig-tailed macaques have suggested a multi-leveled society with harem-type unit groups. However, in the present study, the troops observed had neither a substructure similar to harem-type groups nor a superstructure that emerged as a result of fusion of the troops. The unit group of the pig-tailed macaques appears to be a multi-male, matrilineal group.

Context modulates signal meaning in primate communication

“…We analyzed behavior of adults and subadults (n ϭ 48) because the dominance relationships of juveniles are not yet established. The demographics of our captive population were similar to those reported for natural populations (27)(28)(29) in that males were removed at puberty, females remained in their natal groups, forming matrilines, and adult males were introduced and removed every four years.…”

Life after logging: reconciling wildlife conservation and production forestry in Indonesian Borneo

“…); density: 52.8 ind/km 2 or 0.94 troops/km 2 (Oi 1990). Occurrence on small SE Asian islands Alange, Bangka, Bedung, Iyan, Kangean, Klum, Lingung Nias, Payong and Si Chang (n = 10 +) (Meijaard 2003b).…”

“…Social behaviour Multimale-multifemale matrilineal groups with matrilineal dominance hierarchy; fi ssion/fusion (see footnote under Long-tailed Macaque); average group size of 36 (range 6-81) (Oi 1990), 15-40 (Caldecott 1986, but apparently also seen in larger (>100) groups that are split into loosely-lined subgroups for foraging (Duckworth pers. obs.…”

“…); density: 52.8 ind/km 2 or 0.94 troops/km 2 (Oi 1990). Occurrence on small SE Asian islands Alange, Bangka, Bedung, Iyan, Kangean, Klum, Lingung Nias, Payong and Si Chang (n = 10 +) (Meijaard 2003b).Genus/species age 7.5 Mya/5.0 Mya Habitat Prefers lowland dipterocarp and secondary forests; higher abundance in old secondary compared to primary forest, but not observed in young secondary or riverine forests (Nijman 1997); occasionally seen in plantations (Yasuma & Andau 2000); found up to 1,700 m (Caldecott 1986); also found in coastal, swamp, dry land and montane forest (Caldecott 1986).Activity Terrestrial and arboreal; less terrestrial than M. fascicularis , although this probably depends on forest type; 50% of time on ground, and rest of time evenly distributed arboreally up to 30 m (Nijman 1997); but Caldecott (1986) found use of the ground 8.4%, lower canopy 33.8%, middle canopy 47.4%, upper canopy 10.4% (Caldecott 1986).Movements and migration Home range 62-828 ha (Caldecott 1986); day range 2,000 m (Wrangham et al 1983); males disperse at 5 years of age and remain solitary or peripheral to a group.Feeding ecology Primarily frugivorous; fruit 88%; leaves 22% (Rodman 1978); 73.8% fruit and seeds, 12.2% animal prey (including insects, nestling birds, termite eggs and larvae, and river crabs), 5.4% leaves, 3% buds, 1.1% fl owers (Caldecott 1986).Social behaviour Multimale-multifemale matrilineal groups with matrilineal dominance hierarchy; fi ssion/fusion (see footnote under Long-tailed Macaque); average group size of 36 (range 6-81) (Oi 1990), 15-40 (Caldecott 1986, but apparently also seen in larger (>100) groups that are split into loosely-lined subgroups for foraging (Duckworth pers. obs.…”

Hutan pasca pemanenan: melindungi satwa liar dalam kegiatan hutan produksi di Kalimantan

“…); kepadatan: 52,8 ind/km 2 atau 0.94 kelompok/km 2 (Oi 1990). Keberadaan di pulau kecil di Asia Tenggara Alange, Bangka, Bedung, Iyan, Kangean, Klum, Lingung Nias, Payong dan Si Chang (n = 10 +) (Meijaard 2003b).…”