"I managed to catch a glimpse of its tail", "I saw its shadow," "Lucky if you spot one!"This usual banter among tourists at the tiny Keibul Lamjao National Park (KLNP) in Manipur -- the world's only floating national park -- is not about catching the Unicorn.They are talking about the endangered and elusive Sangai or Eld's deer -- popularly known as the "dancing deer" by the locals. Celebrated for its gait, it is ubiquitous in Manipuri art, culture and folklore.Now untreated human waste is threatening its already jeopardised survival at the park, its last remaining refuge.Spread around 40 square kilometres, KLNP is the protected southern rim of the saucer-shaped freshwater lake, the iconic Loktak, and is about a quarter of the size of Assam's famous Kaziranga National Park.The swampy Loktak, originally a "wetland of wetlands" and the "lifeline" of the Manipur Valley's people, is famous for the phumdis -- the squelchy mass of vegetation, soil and organic matter bunched together and in various stages of decomposition -- that has thickened to form floating meadows.It is the largest freshwater lake in northeast India, bordering Myanmar and straddling the Barak-Chindwin river basin in the Indo-Myanmar region.At Sendra, the highest point of the lake, about an hour-and-a-half's drive from state capital Imphal, one gets a bird's eye-view of the phumdis dotting the water body.
Rings of green stretching across the clear blue expanse of the lake bring to mind images of crop circles synonymous with rumours of alien visitors.These floating meadows harbour around 260 of the animals, whose dainty gait is said to inspire Manipuri dance traditions and folklore.Under attack from water pollution due to untreated waste, these islets have thinned down -- making it tough for the deer to live on and off them.Of the 40 square km of the national park, about 65 per cent (26 square kilometre) is covered with thick and almost contiguous mat of floating meadows."To support the weight of Sangai (weighing between 90 kg and 150 kg) and sustain a stable population of the deer, the phumdis needs to be at least a metre thick," Chongpi Tuboi of the Wildlife Institute of India (WII) told IANS.Tuboi, a project scientist, in the WII's conservation action plan for Sangai, says the phumdis that have formed recently (it may take up to 20 years for one phumdi to form) are less than a metre in thickness."Overall, only nine square kilometres of the total park area has the required phumdi thickness of at least one metre," Tuboi said.
Loktak's water woes are mainly linked to loss of vegetation cover in its catchment and construction of the Ithai Barrage in the southern part of the lake.While poor water quality has altered the vegetation cover and composition of the phumdis and hence their potential to sustain the Sangais, the construction of the barrage in 1983 disrupted the waterbody's natural flushing mechanism."The Lake was a seasonally flooded wetland with several small wetlands which used to be separated during low water levels and merged into one during the monsoon," Tuboi explained.After the construction of the barrage, the water level in the Lake is maintained at a regular 769.12 metres above mean sea level so as to support the hydro-power project.The lake is, as Tuboi says, in stress due to "permanent flooding".
This hinders the phumdis from settling down on to the water bed during the dry season and picking up nutrients and soil to maintain the desired thickness.From 2008 to 2010, Tuboi and his colleagues Syed Ainul Hussain and Michelle Irengbam tested water samples across 11 sites of the wetland, which is fed by around 30 rivers and streams, including the heavily polluted Nambul and Nambol rivers.The Ithai Barrage is the only outlet for this lake.Both liquid effluents and solid wastes discharged from Imphal city are drained directly into Loktak via the Nambul river which flows through the city.The results of the study published in journal Physics and Chemistry of the Earth in October reinforce the message that the Loktak lake is "severely polluted" due to the "influx of sewage and other wastes from the Nambul and Nambol rivers."
In addition, surface runoff from the surrounding agricultural and catchment areas is also diminishing the lake's water quality, as indicated by high nitrogen concentration.The researchers recommend setting up sewage treatment plants at strategic locations, such as at the inlet channel at Toubul village, which is surrounded by the lake.Meanwhile, Tuboi and his team have been surveying spots within the lake where a satellite population of the Sangai could be re-located."Sangai is the flagship species. If we save it, we save everything else. Before the fragile balance between the lake ecosystem and the local cultural practices are permanently lost, the lake needs to be restored by improving its water quality and hydrological regime," Tuboi added.