Teluk Kelumpang

Teluk Kelumpang, Selat Laut and Selat Sebuku Nature Reserve (Cagar Alam Teluk Kelumpang, Selat Laut dan Selat Sebuku) is a coastal strict nature reserve of about 666 square kilometers (66,650 hectares) in the Kotabaru region of South Kalimantan, Indonesia. ^[1] Designated in September 1981 through Minister of Agriculture Decree No. 827/KPTS/UM/9/81 and managed by the South Kalimantan Natural Resources Conservation Agency (BKSDA Kalsel) under the Ministry of Environment and Forestry, it protects an extensive system of mangroves, tidal flats, estuaries, and adjacent lowland forest along the Makassar Strait coastline near Kotabaru. As a cagar alam (strict nature reserve), it carries Indonesia's highest level of protection, prioritizing the preservation of natural ecosystems and biodiversity over public recreation.

The reserve's coastal and mangrove habitats support a rich assemblage of wildlife, including proboscis monkeys (Nasalis larvatus), endemic to Borneo, long-tailed macaques, and a variety of waterbirds, shorebirds, kingfishers, and herons that depend on the tidal mudflats and estuaries. ^[1] The mangrove and estuarine waters provide nursery habitat for fish, crustaceans, and mollusks, while crocodiles and a range of reptiles inhabit the waterways. These productive wetland ecosystems make the reserve an important refuge for both resident and migratory bird species along the southeastern coast of Kalimantan.

Vegetation is dominated by mangrove forest, with characteristic genera such as Rhizophora, Avicennia, Sonneratia, and Bruguiera fringing the tidal channels and coastline. Nipa palm thrives in brackish estuarine zones, and transitional and lowland forest occurs on higher ground inland of the mangroves. These plant communities are adapted to saline, waterlogged, and tidally influenced soils, and they perform essential ecological functions including shoreline stabilization, sediment trapping, and carbon storage typical of well-developed Bornean mangrove systems.

The reserve occupies a low-lying coastal plain along the Makassar Strait, built up from alluvial and marine sediments deposited by rivers and tidal action. Soft muds, sand bars, and tidal flats characterize the terrain, which is continually reshaped by the deposition and erosion of fine sediment. The flat, waterlogged ground lies near sea level and is laced with tidal channels and estuaries, a geomorphology that creates and sustains the extensive mangrove ecosystems for which the reserve is valued.

The reserve has a hot, humid tropical climate with high rainfall throughout the year and only modest seasonal variation. The wetter months generally fall between November and April under the influence of the monsoon, while the period around the middle of the year tends to be somewhat drier. Coastal conditions, tides, and onshore winds strongly influence the local environment. High humidity and warm temperatures, typically in the high 20s to low 30s degrees Celsius, prevail year-round.

The Kotabaru coast of South Kalimantan has long supported fishing communities and Banjar and other local populations who use its waters, mangroves, and estuaries for fishing, gathering, and small-scale trade. Mangrove areas have traditionally provided timber, fuelwood, and fishing grounds. The designation of the reserve reflects growing recognition of the ecological value of these coastal wetlands and the need to protect them from conversion to fish ponds, settlement, and other development pressures common along Indonesia's tidal coasts. The reserve has faced documented encroachment from oil palm plantations despite its protected status. ^[1]

Teluk Kelumpang, Selat Laut and Selat Sebuku was established as a strict nature reserve (cagar alam) on September 24, 1981, through Minister of Agriculture Decree No. 827/KPTS/UM/9/81, securing protection for one of South Kalimantan's most significant coastal wetland complexes. ^[1] It is administered by BKSDA South Kalimantan under the national Ministry of Environment and Forestry (KLHK/KSDAE). Its cagar alam status restricts activities to research, monitoring, and conservation, reflecting the reserve's primary purpose of safeguarding intact mangrove and estuarine ecosystems.

As a strict nature reserve, Teluk Kelumpang is not developed for general tourism, and access is restricted to permitted research and conservation activities. Its principal values lie in the expansive mangrove forests, tidal estuaries, and the wildlife they support, including proboscis monkeys and abundant birdlife. Any authorized visits are typically conducted by boat through the tidal channels, offering opportunities to observe the coastal ecosystem, though such access requires coordination with the managing authority.

The reserve lies along the coast near Kotabaru, roughly 35 kilometers from the town, and is reached primarily by boat through its network of tidal waterways. There are no tourist facilities, as the area is managed for strict protection rather than recreation. Visitors with legitimate research or conservation purposes must obtain permits and coordinate with the South Kalimantan BKSDA office, and local boat operators provide the practical means of navigating the mangrove channels.

Conservation efforts center on protecting the reserve's large and ecologically valuable mangrove and estuarine ecosystems, which provide fisheries support, coastal protection, and carbon storage. As a strict nature reserve, Teluk Kelumpang is shielded from most extractive use, but it still faces documented pressures including alleged encroachment by oil palm plantations, illegal logging, conversion of mangroves to aquaculture ponds, and sedimentation linked to upstream land use. ^[1] BKSDA South Kalimantan works to monitor and safeguard the area, recognizing its importance for biodiversity and for the resilience of the surrounding coastal communities.