Report indicates static Sangai population
Source: The Sangai Express

Imphal, March 30 2010: The latest study report of Wildlife Institute of India (WII) on the population estimation of Sangai (Brow Antlered Deer) and Hog deer in Keibul Lamjao National Park has maintained that the population of Sangai remains more or less stable though that of Hog Deer has been declining.

Disclosing this to The Sangai Express, a highly placed source said the population estimation of Sangai and Hog Deer in the National Park had been conducted in association with the State Forest Department during 2006, 2007 and 2008 with Syed Ainul Hussain and Ruchi Badola of Wildlife Institute of India as principal investigators.

A copy of the report which was forwarded and received by the Forest Department yesterday pointed out that Sangai was once believed to be extinct from its natural habitat of Keibul Lamjao expanding over an area of 40 sq kms until a small population of around 14 animals was rediscovered in the southern fringe of the Park in 1975.Since then, protection and conservation measures have been taken up.

An observatory tower erected by the State Forest Department for watching Sangai at Keibul Lamjao

According to the WII report, of the total area of the Park, 26 sq km is covered by thick and almost contiguous mat of floating biomass called Phumdi and the remaining 14 sq km is open water and three hillocks.

Within the park, the population of Sangai is largely confined to 20 to 25 sq km area in the southwestern part of the Loktak lake.

In the last population estimation of Sangai which was conducted by the State Forest Department in 2003, the estimated number of Sangai in the park was counted as 180, thus the intrinsic rate of increase in the population between 1975 and 2003 was approximately 10 percent per annum.

The report, however, pointed out that there is potential threat to this endangered species largely because of deteriorating habitat conditions.

The habitat in the Park has deteriorated primarily because of the change in water regime due to construction of Ithai barrage.

The phumdi, which used to settle during lean season and get replenished with soil and nourishment, are now continuously floating resulting in their thinning.

Consequently, they are increasingly becoming defunct in supporting the weight of the deer.

Besides, the release of water from the Ithai barrage, drifting of phumdi towards north reduces availability of phumdi to Sangai.

The report also noted that inspite of strict protection measures, there is competition between Sangai and Hog Deer and the domestic livestock for grazing in the park area, the report said.

It is said that distance sampling methods had been used to derive the population estimation of Sangai and Hog Deer in the study spanning across 2006,2007 and 2008 .

Accordingly, it was arrived at that the estimated density of Sangai was 4.04, 4.08 and 4.05 individuals per sq km during 2006, 2007 and 2008 respectively, with a minimum of 2.97 individual per sq km and maximum of 6.01 individuals per sq km at 95 percent confidence level.

This yielded the estimated mean population size of Sangai as 91, 88 and 92 respectively during 2006,2007 and 2008 with a minimum of 60 and maximum of 136 Sangais at 95 percent confidence level, thus indicating that population of Sangai in the Park is more or less stable.

On the other hand, the estimated density of Hog deer, whose presence were recorded in 22.04-22.73 sq km area of the park, was 2.93, 2.75 and 25.1 during 2006, 2007 and 2008 respectively with a minimum of 1.82 individual per sq km and maximum of 4.32 individuals per sq km at 95 percent confidence level.

This yielded that the estimated mean population of Hog Deer as 65, 61 and 57 individuals during 2006, 2007 and 2008 respectively, with a minimum of 41 and maximum of 96 Hog Deer at 95 percent confidence level, thus revealing a declining trend of Hog Deer population in the Park.

However, it has been cautioned that the estimate derived during this study cannot be compared with the previous data as the method adopted during this study is more rigorous compared to previous methods.

It may be recalled here that only14 Sangais have been recorded when the State Forest Department conducted a population estimation using Helicopter in 1975 and only 98 in 1993 and the figure raised to 57 in 1984 and 180 in 2003 when population estimation was conducted using block count.