Taninthayi Forest Corridor

Description

The Taninthayi Forest Corridor (TFC) is one of the largest remaining areas of unprotected low and mid-elevation, seasonal evergreen forest in Southeast Asia. It is located in the Taninthayi Range that straddles the southern Thai-Myanmar border and contains a multitude of globally threatened species. Taninthayi and Lenya National Parks (TNP, LNP) were proposed in 2002, followed by LNP Extension in 2004, but none have been gazetted. Between TNP and LNP Extension there is a 65-km gap. This gap, which is partially covered by the Thagyet Reserved Forest (TRF), covers 290,100 hectares. If this and the other proposed NPs were gazetted, they would form a contiguous 1 million-hectare corridor stretching from TNP in the north to LNP in the south, a distance of 280 km.

The TFC lies within the northern section of the Indochinese-Sundaic zoological transition zone, which divides Indo-Chinese flora and fauna from Sundaic species (Hughes et al. 2003). The corridor contains some of the southernmost dry seasonal evergreen forests before they transition to aseasonal wet evergreen forest further to the south. It provides habitat for several EN species including the Asian Elephant, Gurney’s Pitta, and Sunda Pangolin.

The four parts of the corridor are described summarized below:

TNP

Location: 12°41'16” N, 98°10'32” E; Area: 364,284 hectares

The northernmost of the four parts, TNP was proposed in 2002. It consists primarily of evergreen forest. It is home to the world’s smallest known mammal, the VU Kitti’s Hog-Nosed Bat (Craseonycteris thonglongyai). This species is only known from in small colonies in southern Myanmar and adjacent Thailand (Bates et al. 2008; Pereira et al. 2006-10). TNP is contiguous with 482,225-hectare Kaeng Krachan NP, which was added to Thailand’s TL in 2011 for criterion x (UNESCO World Heritage Centre 2013). The eastern boundary follows the Taninthayi River, which also forms the border between Myanmar and Thailand.

TRF

Location: 12°05'31” N, 99°21'24” E, Area: 290,100 hectares

The 65 km gap between TNP and LNP is unprotected.  It is partly covered by the TRF. From inspection of satellite images, the forest cover is in good condition and the area is believed to have similar values to TNP.  But no biodiversity surveys have been carried out here for security reasons. It would lie next to Kuiburi NP in Thailand.

LNP Extension

Location: 11°35'37" N, 99°19'30 E, Area: 185,258 hectares

L NP and LNP Extension were proposed following the discovery of a large population of Gurney’s Pitta (Pitta gurneyi), which resulted in its conservation status changing CR to EN. LNP Extension (also known as the Nawun Reserved Forest) contains 99% of the global population of the species (the other 1% is in Thailand). The extension includes similar habitat to both TNP and LNP.  LNP Extension is contiguous with Thailand’s Sadeth Naikrom-Krom Luang Chumporn (North) Wildlife Sanctuary.

LNP

Location: 11°08'47” N, 99°03'01" E, Area: 184,792 hectares

L NP shares a border with Namtok Huai Yang NP in Thailand and is composed of seasonal lowland and mid-elevation seasonal evergreen forest. It shares the natural values and characteristics of the other parts of the corridor. Some of LNP is being used for logging and has been allocated for palm oil plantations.

Justification of Outstanding Universal Value

TFC contains the largest remaining block of lowland evergreen forest in Mainland Southeast Asia. Its position in the transition zone between Indo-Chinese and Sundaic flora and fauna give it a high diversity of both locally endemic and globally threatened species. This transition zone is recognized as one of the most biologically diverse regions in the world (Woodruff 2010).  The series of range disjunctions that occur in this transition create a unique assemblage of flora and fauna from both biogeographic zones, creating globally distinct species assemblages.  They also shed light on the evolutionary interplay between habitat type, ecological history, and species range.

The four parts of the property cover more than 1-million hectares and include sufficient elevation range and habitat types to preserve the diverse flora and fauna of the region. If all four sections are gazetted, they connect meta-populations over a large contiguous area and provide a north-south corridor for adaptation to climate change.  The size of the corridor is also provides opportunity to conserve wide-ranging species including the Tiger, Asian Elephant, and Plain-pouched Hornbill.  In 2004, 100-150 elephants were thought to be in the corridor (Leimgruber et al. 2011).  Conservation of the property is essential for the survival of Gurney’s Pitta. The corridor’s value is further augmented by its connection to more than 6 million hectares of protected area in Thailand, including more than 482,000 hectares nominated as a WHS.  These properties together provide an outstanding potential for conserving wet and lowland evergreen forests in Southeast Asia at a landscape scale.

Criterion (ix): The TFC would form one of the largest protected areas of lowland and mid-elevation evergreen forest in Southeast Asia, preserving ecological and evolutionary processes over 1 million hectares.  It also provides insights into the history of these processes by encompassing the transition zone between Indo-Chinese and Sundaic biogeographical regions.  The floral and faunal transitions are gradual and disjunct, providing an area rich in opportunities for the study of biogeography.

Criterion (x): The property contains multiple threatened and regionally-endemic species. LNP and LNP Extension hold 99% of the global population of the Gurney’s Pitta and are critical for its continued survival. In addition, the TFC serves as a refuge for Sundaic species that have seen their numbers decrease as palm oil plantations have spread across similar forest Thailand and Malaysia. Key animal species for LNP and LNP Extension (many of which are likely present in Taninthayi NP as well) include (Myanmar Biodiversity (2012):

Statements of authenticity and/or integrity

The TFC is large enough to preserve both ecosystem processes and provide habitat for key species, especially considering contiguous protected areas across the border in Thailand.  It contains some of the largest areas of lowland evergreen forest that have not been converted to plantation in Southeast Asia. While wildlife trade does occur, it may be at relatively lower rates for some species, such as the Sunda Pangolin, under heavy commercial hunting pressure in other parts of Southeast Asia. Major threats are rubber and oil palm concessions inside and outside of proposed protected areas.

Satellite images show deforestation and apparent conversion to agriculture in the southwest corner of TNP. TNP Extension is crossed by a dirt road between Myeik (Myanmar) and Prachuap Khiri Khan (Thailand) that passes a 400-hectare Nong Bwa coalmine near its southern border with LNP Extension. This road may be upgraded in the near future, which would increase access to interior parts of LNP Extension. A Myanmar Timber Enterprises concession overlaps with part of the TNP Extension.

Both LNP and LNP Extension have overlapping concessions.  Satellite images for LNP show deforestation and agricultural plantations in the southeast corner (more easily accessible from Thailand). Small areas of agricultural cultivation are visible in riparian areas in northern LNP Extension. Although these areas are relatively small, they should be excluded from any gazetted protected areas. Of the four parts, TNP would be the most straightforward to gazette because it has no overlapping concessions. However, the value of the corridor lies in its size.  One approach would be to nominate these areas in stages.

Comparison with other similar properties

The most similar property in terms of size and habitat is the Kaeng Krachan Forest Complex (KKFC) in Thailand. It ranges in elevation from 100m to 1,500 m and is made up of three protected areas: Mae Nam Phachi Wildlife Sanctuary, Kaeng Krachan NP, and Kui Buri NP. Kaeng Krachang is the largest NP in Thailand and is also an ASEAN Heritage Park. It is contiguous with TNP.  KKFC is located on the eastern flank of the Tenasserim Range (12°53'20” N, 99°24'28” E) and is part of the larger Western Forest Complex (WFC) of Thailand. Its climate is similar to sites across the border in Myanmar, characterized by year-round humidity and a rainy season (May-October), cool season (October-February), and dry season (February-May). It is 85% covered by evergreen rainforest that provides habitat for similar species as found in TFC.

TFC connects to more than 6 million hectares of protected area in Thailand, including more than 482,000 hectares nominated as a WHS. The continuity between these areas and the TFC provides great potential for a transboundary property. The survival of wide-ranging wildlife would be enhanced by management that encompasses their full range. Conservation work in Thailand’s WFC has shown that tiger populations can quickly increase with adequate protection (WCS 2013). A transboundary property would enhance the ability of Thailand and Myanmar to coordinate management of these forests on a landscape scale and better protect wildlife.  While there is no formal cooperation in place, the governments do share information about poaching through the ASEAN Wildlife Enforcement Network and this relationship could be strengthened in the development of a transboundary site.

The Tropical Rainforest Heritage of Sumatra WHS in Indonesia shares a Sundaic species assemblage and some lowland evergreen forests as part of a large elevation gradient from sea level to 3,805 m. However, its locally endemic species and volcanic landscape distinguish it from the TFC. The Heart of Borneo (HoB) Initiative aims to create the largest area of protected lowland evergreen forest in Southeast Asia, covering more than 220,000 km² of Borneo’s central highland rainforests (WWF 2013).  Wildlife found here include the Orangutan (Pongo pygmaeus), Pygmy Elephant (Elephas maximus borneensis), and Sumatran Rhino (Dicerorhinus sumatrensis harrissoni). The HoB area has extremely high plant biodiversity, with more than 15,000 species of plants and 3,000 tree species, and 37 previously unknown species of orchids have been discovered since 2007 (WWF 2013). The TFC is distinguished by its distinct species assemblage and biogeographical value from its location in the transition zone between Sundaic and Indo-Chinese species.  Prey Lang in Cambodia is one of the largest remaining evergreen forests in Mainland Southeast Asia but at 360,000 hectares it is smaller than TFC and is also contains drier evergreen forest.