Dibrugarh: Dibru-Saikhowa National Park, situated in eastern Assam’s Tinsukia district and known for its rich biodiversity, has been facing an existential threat due to unabated erosion caused by surrounding rivers.
Dibru-Saikhowa, with an area of 340 sq km, is among the most vibrant wilderness landscapes and is distinct for its pristine scenic beauty.
The National Park, located in the floodplains of the Brahmaputra, serves as a safe haven for many extremely rare and endangered species of wildlife.
The park, which is surrounded by six rivers—Lohit, Dibang and Disang on the north, and Anantnala, Dangori and Dibru on the south—is also facing a major threat in the form of erosion by these rivers.
“Due to river erosion, Dibru-Saikhowa has been shrinking, and the landmass of the National Park has been going into the river. Every year Dibru-Saikhowa NP has been losing landmass. We are very much concerned about the National Park because if it continues, then one day the National Park will vanish,” said environmentalist Niranta Gohain.
According to official records, over 36 per cent of Dibru-Saikhowa National Park has been eroded in its 25 years of existence, shrinking it to only 216.53 sq km at present.
“Climate change has adversely affected Dibru-Saikhowa National Park, with the massive flood in 2024 inundating half of the National Park, and the constant erosion by rivers posing a serious threat to the park,” said an expert.
The National Park, spread across Dibrugarh and Tinsukia districts in Upper Assam on the bank of the Brahmaputra, was declared a National Park in 1999 with a forest area of 340 sq km.
However, satellite images of 2023 obtained by the Environment and Forest Department of Assam showed that the Park’s present area is only 216.53 sq km.
“The Dibru-Saikhowa National Park is considered the habitat of a variety of flora and fauna such as the White-Winged Wood Duck, Feral Horses, River Dolphins, and migratory birds, but due to the erosion, the flora and fauna are at high risk,” said an expert.
The Dibru-Saikhowa ecosystem consists of moist mixed semi-evergreen forests, moist mixed deciduous forests, canebrakes, and grasslands; it is also the largest Salix swamp forest in northeastern India, with a tropical monsoon climate and abundant rainfall.
“Dibru-Saikhowa witnessed major floods in 2004, 2012, 2017, and due to that, hydrological changes have been observed in the National Park. A major portion of Dibru-Saikhowa was primary grassland, but now, due to flash floods, it has converted into shrubland, destroying the ecology of the park. Day by day, the landmass of Dibru-Saikhowa has been shrinking,” said researcher Imon Abedin.
According to a study, in 2000, grasslands were the dominant land cover (28.78%), followed by semi-evergreen forests (25.58%). By 2013, shrubland became the most prominent class (81.31 sq km), and degraded forest expanded to 75.56 sq km. During this period, substantial areas of grassland (29.94 sq km), degraded forest (10.87 sq km), semi-evergreen forest (12.33 sq km), and bare land (10.50 sq km) were converted to shrubland. In 2024, degraded forest further increased, covering 80.52 sq km (23.47%).
“This change resulted as numerous areas of shrubland (11.46 sq km) and semi-evergreen forest (27.48 sq km) were converted into degraded forest. Furthermore, significant shifts were observed in grassland, shrubland, and degraded forest, indicating a substantial and consistent decline in grassland. These changes are largely attributed to recurring Brahmaputra River floods and increasing anthropogenic pressures,” the study said.
The study recommends a targeted Grassland Recovery Project, control of invasive species, improved surveillance, increased staffing, and the relocation of forest villages to reduce human impact and support community-based conservation efforts.
“Protecting the landscape through informed LULC-based management can help maintain critical habitat patches, mitigate anthropogenic degradation, and enhance the survival prospects of native floral and faunal assemblages in Dibru-Saikhowa National Park,” the study said.
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