Orangutans depend on social learning for the acquisition of survival skills. The development of skills is not usually assessed in rescued orphans’ pre-release. We collected data of seven orphans over an 18-months-period to monitor the progress of ontogenetic changes. The orphans, 1.5–9 years old, were immersed in a natural forest environment with human surrogate mothers and other orphans. Social interactions deviated significantly from those of wild mother-reared immatures. Infants spent more time playing socially with peers, at the expense of resting and solitary play. Infants were also more often and at an earlier age distant from their human surrogate mothers than wild immatures are from their biological mothers. We found important changes towards an orangutan-typical lifestyle in 4- to 7-year-old orphans, corresponding to the weaning age in maternally reared immatures. The older orphans spent less time interacting with human surrogate mothers or peers, started to use the canopy more than lower forest strata and began to sleep in nests in the forest. Their time budgets resembled those of wild adults. In conclusion, juvenile orphans can develop capacities that qualify them as candidates for release back into natural habitat when protected from humanising influences and immersed in a species-typical environment.

Historically, and based on the latest conditions, Samboja Research Forest has a fairly high vulnerability to the presence of invasive species that can interfere with ecosystem stability and forest succession. However, data collection and risk assessment of invasive species have not been conducted in the forest area. The study was carried out to support the management of Samboja Research Forest, particularly in controlling invasive species. The study was conducted with exploration techniques in open areas, secondary forests, and primary forests. The density and frequency data of invasive plants were obtained using random plots in secondary and primary forest areas. The results showed the presence of 52 invasive plant species in the Samboja Research Forest area with dominance by shrubs and herbs. Based on plants distribution and density, four crucial invasive plant species in Samboja Research Forest were identified, namely: Acacia mangium, Spathodea campanulata, Miconia crenata, and Piper aduncum. The management of invasive species was carried out in two stages, short term, through manual weeding, and in the long term, with the prevention, eradication, and periodic risk assessment.Keywords: invasive alien species, Kalimantan, eradication, Spathodea campanulata

Indonesia is the largest archipelagic country in the world, with 17,000 islands of varying sizes and elevations, from lowlands to very high mountains, stretching more than 5000 km eastward from Sabang in Aceh to Merauke in Papua. Although occupying only 1.3% of the world’s land area, Indonesia possesses the third-largest rainforest and the second-highest level of biodiversity, with very high species diversity and endemism. However, during the last two decades, Indonesia has been known as a country with a high level of deforestation, a producer of smoke from burning forests and land, and a producer of carbon emissions. The aim of this paper is to review the environmental history and the long process of Indonesian forest management towards achieving environmental sustainability and community welfare. To do this, we analyze the milestones of Indonesian forest management history, present and future challenges, and provide strategic recommendations toward a viable Sustainable Forest Management (SFM) system. Our review showed that the history of forestry management in Indonesia has evolved through a long process, especially related to contestation over the control of natural resources and supporting policies and regulations. During the process, many efforts have been applied to reduce the deforestation rate, such as a moratorium on permitting primary natural forest and peat land, land rehabilitation and soil conservation, environmental protection, and other significant regulations. Therefore, these efforts should be maintained and improved continuously in the future due to their significant positive impacts on a variety of forest areas toward the achievement of viable SFM. Finally, we conclude that the Indonesian government has struggled to formulate sustainable forest management policies that balance economic, ecological, and social needs, among others, through developing and implementing social forestry instruments, developing and implementing human resource capacity, increasing community literacy, strengthening forest governance by eliminating ambiguity and overlapping regulations, simplification of bureaucracy, revitalization of traditional wisdom, and fair law enforcement.

Three new Begonia species from Kalimantan, Indonesian Borneo are described here, namely Begonia kapuashuluensis, B. patar and B. sangkulirangensis, and one species is reported as a new record for Kalimantan. Colour plates, as well as notes on distribution, habitat and conservation status are provided. On conservation status, we provisionally assess B. kapuashuluensis as near threatened, B. patar as critically endangered and B. sangkulirangensis as vulnerable.

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