Comparisons of food availability and group density of Japanese macaques in primary, naturally regenerated, and plantation forests

Abstract

We compared food availability and group density of Japanese macaques in Yakushima, southern Japan, among primary forest and two habitats that had been disturbed by logging and had different regeneration histories. The study was conducted in an undisturbed national park, forest that was logged 7-18 years ago and later naturally regenerated, and forest that was logged 19-27 years ago and later planted with Japanese cedar (Cryptomeria japonica) trees. The plantation forest was primarily composed of large Cryptomeria japonica trees at low stand density, while the naturally regenerated forest was composed of many small trees. The total basal area and number of trees in the primary forest were comparable to those in the plantation forest. Annual fruit production was greatest in the naturally regenerated forest, intermediate in the primary forest, and negligible in the plantation forest. Herb availability was high in the naturally regenerated forest, but low in the primary and plantation forests. The group density of Japanese macaques was high in the naturally regenerated forest, intermediate in the primary forest, and low in the plantation forest. Since group size in the naturally regenerated forest was small, individual density was almost the same as in the primary forest. These results suggest that the effects of regeneration on macaques vary between the two habitats. The plantation forest consisted mostly of Cryptomeria japonica, which supplies only flowers as food in a limited season, and had a lower density of macaques. On the other hand, in the naturally regenerated forest, fruit production and herb availability were high (probably because of the enhanced light conditions after logging), and the density of macaques was as high as in the primary forest.

Sleeping site selection of Francois’s langur (Trachypithecus francoisi) in two habitats in Mayanghe National Nature Reserve, Guizhou, China

“…We estimated annual wild fruit production by noting the number of fleshy fruits on marked branches of each tree. When this was impossible, we estimated the total fruits of an individual tree by the percentage in volume of the branch to the total crown (Haya et al 2005). Crop fruit availability was estimated on the basis of the plantation area of crops in the home range.…”

Assessing the diversity of dung beetle assemblages utilizing Japanese monkey feces in cool-temperate forests

“…These microsites are generally avoided by forest dung beetle species (Sasayama et al 1984;Halffter and Arellano 2002). Shrubby or climbing plants that bear berries flourish at these microsites in temperate forests; therefore, most frugivorous mammalian fauna, including monkeys, are attracted to such secondary forests (Hanya et al 2005). In fact, the density of the monkey population in secondary forests was the highest in the study area (see the section ''Study animals'').…”

“…Mature cedar-plantation with a closed canopy is generally of small value in providing feeding sites for monkeys (Hanya et al 2005;Agetsuma 2007), indicating that the supply of monkey feces could be small in this type of forest. Our results showed the biomass of the core species (i.e.…”

Variability in habitat, diet, and social structure ofHapalemur griseus in Ranomafana National Park, Madagascar

“…Second, the success of conservation efforts will depend on what tree species have been removed and introduced, and the regenerative capacity of the forest (Struhsaker, 1997). Third, the effects of logging in particular will depend on the system of logging employed and the time since logging occurred (Hanya et al, 2005). Finally, successful conservation will depend on the flexibility of the primate species themselves, and their ability to alter their diet and social structure according to the existing habitat (Janson and Chapman, 1999;Struhsaker, 1997;Gonzalez-Solis et al, 2001).…”