The Siang River is a transboundary river which flows in Tibetan plateau, China in the name of Yarlung Psangpo and after entering India in Arunachal Pradesh, it is known as Siang which meets river Brahmaputra in Assam, 230 km downstream.
The Siang river valley is home to many tribal communities who are dependent on the river for their livelihood. The ichthyofaunal diversity recorded 82 fish species belonging to eight orders, 24 families and 53 genera in the river (Das et al, 2014). This river is a lifeline to Arunachal Pradesh and Assam and supports the livelihood of the populace, human health, economic growth and ecological diversity.
The communities adjoining the river are dependent on the river for their household consumption. Some of them also depend on the river for their livelihood through fishing. But in the last two years due to habitat alteration, there is a sharp decline in fish catch from the river, which is directly affecting the livelihood of the fishermen community. A case of a migratory fisherman from Bihar, Ramesha Sahani, depicts the critical situation of the fishers in the Siang River. The river is a common pool resource and the word “fishing” is directly related to capture fisheries and those who are involved in such activities are called fishers. Fishers belong to the lower strata of society. Sahani primarily belongs to the fishermen community of Bihar where they migrate to other parts of the country to earn their livelihood. This migration may happen due to the favourable climate, better availability of fish, lesser competition, profitable employment, the availability of natural resources for fishing, lack of a job in native place, better availability of food supply etc.
Fishers migrate for livelihood
Migration is a well-known livelihood strategy among the populace dependent on common pool resources for their livelihoods. Sahani from Barye village, Chhapra in Bihar is engaged in fishing since the 1990s in the Brahmaputra and the Siang rivers. The factors that motivated him to migrate from Chhapra to Oiramghat, Assam include unemployment, low income, poverty, migration of his relatives and villagers to the Siang and the Brahmaputra river areas.
He is a fulltime fisher, exclusively dependent on the Siang for the last 10 years. Fishing is performed/practised for almost nine months in a year, except the abrupt monsoonal months due to heavy flood situation which may threaten the lives of him and others like him. For the last two years, he is getting very less fish from the river. Earlier, his monthly income, excluding operational cost and consumption cost, was Rs 10,000-Rs 12,000 per month. Since October 2017, however, due to changing water environment of the river, his gross monthly average income has come down to Rs 7000. It was reported by ICAR- Central Inland Fisheries Research Institute, Barrackpore during October 2017 that the river water suddenly turned grayish-black and muddy owing to the presence of unusual slag and silts. The thick layer of sediment has accumulated over stretches of the river bed and contributed to the high magnitude of turbidity of river water. This disturbed the inherent biota of the river.
Earlier in 2017 (prior to this perturbation/adverse condition), Sahani used to stay in the sandy islands of the river (locally known as Char in Assam) for nine months for fishing in a temporary shack. But in 2018, he stayed only for five months due to the diminution of his income. He says that fishing from river Siang is no more profitable venture due to the stiff decline of fish catch from the river. He perceives that high turbidity and heavy siltation have changed the river habitat which has caused mortality or recruitment failure in fishes of the Siang.
Change in water condition leads to decline in fish catch
The socio-economic survey of the local populace and other migrant fishers by a team of scientists of ICAR-CIFRI, Barrackpore in Oiramgat and Pasighat areas shows that there was a sharp decline in fish catch over the last two years due to continuous uncongenial water condition in the river, which may be the root cause of an average of 35 percent turn down in the income of the migratory fishermen. The catch per unit effort has also declined (1-4kg/km), which is roughly one-fourth of the catch per unit length of the river in 2015-16. People living along the Siang River also perceives that the unnatural muddy and sticky suspended particles may cause distress situation for the fish in the river.
In October 2017, The ICAR-CIFRI team recorded the water transparency <4.0 cm across the stretch and turbidity ranged from 258-405 NTU against the permissible range of <10NTU as per ISI and CPCB. The considerable higher turbidity indicates an unnatural high particle load in the water compared to the observations made during 2014 (92.1-99.8 NTU). The low abundance of phytoplankton (55-936 ul-1 ) was also recorded during the period. These adverse attributes are directly affecting the aquatic biodiversity of the rivers which is ultimately distressing the livelihood of the fishermen including migratory fishermen.
Fishermen migrate to sustain their lives and livelihoods. Due to economic, social and technical factors, fishers are not able to earn adequately to meet their essential needs. Thus, available natural resources play a crucial role in uplifting the economic status and livelihood of fishers. If these resources are at risk, it will affect the lives and livelihoods of the poor fishers as well. Hence, it is imperative to sustain the aquatic diversity and the river-dependent livelihoods.
Disclaimer: The views and opinions expressed in this article are those of the author/s and do not necessarily reflect the policy or position of India Water Portal.