1. Sustaining species and ecosystems

Priority will be given towards implementing inventories and assessment of the conservation status of Rare, Threated or Endangered species, and the development of relevant management strategies for their long-term survival.

For aquatic Communities inventories of naturally occurring species have been Initiated, along with a stepwise assessment of the commercial value of any of those studied. This information will form the basis for developing programs for sustainable consumptive use of aquatic resources, non-consumptive use (recreation and nature tourism. Further on, a study of habitat restoration will also be implemented.

Studies of exotic and/or invasive species will determine effective methods of economic use, control or eradication; habitat restoration including replanting of species of long-term economic or conservation value; non-consumptive use including recreation and tourism. Appropriate effective long-term protocols for commercial harvest and sustainable use for all species are being assembled. Effective methods of economic use, eradication or long-term management of exotic / invasive species, to remove or mitigate large-scale negative economic impacts, will be implemented via biological control or economic exploitation. Support for the control of faunal species causing intermittent disturbance to subsistence agriculture, or endangering human life or property. Close cooperation and coordination is sought from relevant local and regional government authorities in these endeavors.


Species conservation targets

Surveys by Yayasan Ulin’s partner scientists and a conservation staff have been conducted on a regular basis since 2009, and have indicated that healthy populations of both the Critically Endangered Siamese Crocodile (Crocodylus siamensis) and the Endangered Sunda Gharial (Tomistoma schlegelii) currently persist, but remain threatened by human activities, including plantation agriculture. At least seven Critically Endangered, or Endangered Species have been confirmed occupy the various terrestrial and aquatic habitats in Mesangat. Those confirmed and their current conservation status are listed below.


* IUCN Redlist of species

** CE = Crotocally Endangered, E = Endangered, V = Vulnerable


Population monitoring

Initial findings of studies on the population ecology of the crocodiles Crocodylus siamensis and Tomistoma schlegelii) were published in 2018, and long-term monitoring efforts of these populations are in progress. YU has also currently entered into a research MoU with the Faculty of Science and Mathematics of Universitas Mulawarman – Samarinda, in Kalimantan Timur. In addition to crocodile monitoring and assessment inventories of the mammal fauna, with a focus on the flat-headed cat, and for herpetofauna and population studies of Orlitia borneensis will be priorities for 2019. An update on earlier fish, crustacean and botanical surveys is also planned.

Commercial harvest and management

Crocodile species, are accidentally caught on hooks by the fishermen, who are compensated by a small payment to report these animals to the Foundation so that staff may obtain morphometric and spatial data. A compensation and release program with local subsistence fishermen, for hook removal, and measurement of body parameters, and tagging, suspended since 2011, has been resumed in January 2017, Furthermore, records of unusual species (or their nests) from local people are formally documented by entry into a permanent database. The YU staff are hoping to resume monitoring the catch of all consumptively used fish and turtle species by fishermen of the raft village of the wetland. Future research projects will concentrate on detailed studies for long-term management.

Control and consumptive use of exotic species

The highly disturbed areas of Danau Mesangat and it neighboring wetland, Kenohan Suwi, are now inhabited by a full range exotic species, either inadvertently or intentionally introduced. Among others are the aquatic water hyacinth (Eichornia crassipes) and water fern (Salvinia molesta). The latter have invaded extensive areas of open water, choking off waterways formerly used by fishermen to reach many of their favorite areas, and at some other sites creating excess biomass that rots to fomr mats of dead vegetation leading to senescence of these areas and the odor of toxic hydrogen sulfide from anaerobic decomposition. YU has joined with the Southeast Asia Center for Tropical Biology to introduce biological control by two herbivorous weevils specific to the plants in question. YU staff will be trained in the culture, release and monitoring of these insects, for their eventual control or eradication.

The apple snail (Pomacea canaliculata), South American sucker catfish (Hypostomus plecostomus) and the East Asian Snakehead (Channa micropeltes) are among the abundant animal exotics that could potentially be included in consumptive use. The East Asian Snakehead is already commercially harvested by local fishermen, but for commercial use of the others, further studies are needed.

Headstarting and Reintroduction

Headstarting of C. siamensis, T. schlegelii and O. borneensis through collection and incubation of eggs or assisting groeth of juveniles in captivity until the latter are no longer threatened by predators, are being considered to extend these populations back to occupy their original range in Kalimantan Timur. Such programs also have the potential as an additional draw for ecotourism in the Mesangat area.

2. RTE species and current threats

To overcome threats ,YU and REA KON[1] staff, in cooperation with the staff and students of local and international universities have identified, visited and photographed approximately 50 sites occupied by RTE species (Appendix IB ) throughout Mesangat and Kenohan Suwi. which include: Moderate to severe alteration of natural habitats (e.g., for estate crops (oil palm, or timber extraction), Such as uncontrolled timber extraction and often disastrous dry season fires Invasive exotics (Eichornia crassipes water hyacinth, Salvinia sp water fern, apple snails) must be controlled, and may possibly be turned into consumptively used species. Contrarily, unsustainable harvest and sale of and natural species or disturbance of their feeding or reproduction: i.e., collection of crocodile eggs, harvest and sale of riverine/wetland turtles, hunting of monkeys as food, accidental or intentional capture of species with fishing gear, rearing Endangered species as pets, etc must be curbed or eliminated.

Currently, invasive water weeds are controlled through the use of toxic chemical pesticides obtained from agriculture supply stores, so that better means of control must be sought.

The most serious threat lies with potential large-scale conversion of natural wetland habitats for plantation agriculture, that has slowed in recent years, but not ceased. Fortunately, use of the higher ground to plant oil palm by smallholders is currently controlled and not considered a threat (because suitable areas are small, and located away from the core wetland areas). More troubling is the complete removal of all natural vegetation (and the bulldozing of rivers) by irresponsible plantation companies for maximizing the amount of oil palm that can be planted. This results in serious erosion and subsequent siltation of the river and wetlands, an impact that is increasingly seen in higher flood levels and longer duration of these seriously destructive floods. Fertilizer runoff from plantations is also assumed to have stimulated rapid growth of exotic invasive plants, which can lead to rapid senescence in certain sections of the Mesangat and Suwi habitat.

3. Physical parameters

Weather data (Oregon Scientific automatic weather station) and water levels (standing indicator) are recorded daily at the YU’s Raft station, downloaded, reported monthly and archived.

4. Monitoring of local flora/fauna

In a YU “Compensate and Release” program, in which traditional fishermen notify YU of any crocodiles or turtles accidentally captured on their fish hooks or in fish traps, and are then paid a visit by YU staff. The fisherman is paid a small compensation (USD1.00-2.00) in return, any hook carefully removed from the jaw or throat, whereupon the animal is sexed, weighed, measure, tagged with a small number, and released at the point of capture.