Sumatran orangutans are primarily frugivores, favoring when it is available fruit that is soft and has pulp, and feeding on figs when it is not. Insects, plants, vegetables and bark also contribute to Sumatran orangutan diet, however these contributions are much less significant than that of the fruit.
The figs they consume do not fruit on a seasonal basis, meaning they are generally available at any given time of the year (WICH). Unlike figs, the fruiting of soft pulpy fruits does occur on a seasonal basis, however it is also altitude dependent, so orangutans are able to access this preferred food during multiple seasons by relocating between altitudes (within their home range) (BUIJ). The combination of availability of figs year-round and …show more content…
A close relative of the Sumatran orangutan, the Bornean orangutan (Pongo Pygmaeus), is affected by these mast seeding occurrences and their diets are modified to include a higher percentage of plants and leaves during years of lower fruit production. This is not the case, however, for Sumatran orangutans because even in years of low fruit production, they are still able to maintain their fruit intake due to higher output of figs in Sumatra. While mast seedings have correlated with decreased fertility and reproduction rates in Bornean orangutans, Sumatran orangutan fertility and reproduction rates have been found to be unaffected by it. …show more content…
Out of three categories of male orangutans (dominant adult males, other adult males and subadult/flanged males) dominant males have the smallest home ranges, which corresponds to their decreased difficulty in finding a mate due to their sexual favorability. Other adult males and subadult males require larger home ranges in order to allow them to find a female who will willingly mate with them, or in the case of subadult males, who can be overpowered. Males of this species, like females do not display territorial behavior and individual’s home ranges, again, often overlap.
The figs they consume do not fruit on a seasonal basis, meaning they are generally available at any given time of the year (WICH). Unlike figs, the fruiting of soft pulpy fruits does occur on a seasonal basis, however it is also altitude dependent, so orangutans are able to access this preferred food during multiple seasons by relocating between altitudes (within their home range) (BUIJ). The combination of availability of figs year-round and …show more content…
A close relative of the Sumatran orangutan, the Bornean orangutan (Pongo Pygmaeus), is affected by these mast seeding occurrences and their diets are modified to include a higher percentage of plants and leaves during years of lower fruit production. This is not the case, however, for Sumatran orangutans because even in years of low fruit production, they are still able to maintain their fruit intake due to higher output of figs in Sumatra. While mast seedings have correlated with decreased fertility and reproduction rates in Bornean orangutans, Sumatran orangutan fertility and reproduction rates have been found to be unaffected by it. …show more content…
Out of three categories of male orangutans (dominant adult males, other adult males and subadult/flanged males) dominant males have the smallest home ranges, which corresponds to their decreased difficulty in finding a mate due to their sexual favorability. Other adult males and subadult males require larger home ranges in order to allow them to find a female who will willingly mate with them, or in the case of subadult males, who can be overpowered. Males of this species, like females do not display territorial behavior and individual’s home ranges, again, often overlap.