Par­adise lost?

Ma­nipur's rare San­gai deer might soon lose its only habi­tat

Down to Earth - - CONTENTS - ANU­PAM CHAKRAVARTTY

IMAG­INE BE­ING a large mam­mal con­fined to an area of just 10 sq km. Imag­ine sur­viv­ing ge­netic ex­per­i­ments, floods, en­croach­ments, dis­eases and poach­ers, and that too in a wet­land slowly shrink­ing in size. Imag­ine be­ing hon­oured as a state an­i­mal, with fes­ti­vals, news­pa­pers and even TV chan­nels named af­ter you. And sud­denly you find there are barely 200 of your kind left, amidst plans to take away the only habi­tat that nour­ished and pro­tected you.

This is the story of San­gai, a crit­i­cally en­dan­gered brow-antlered deer found in Ma­nipur in a tiny speck of land, mostly grass­lands lo­cally called phumdi that float on wa­ter. South of Lok­tak Lake (a Ram­sar site) in Moirang dis­trict lies the only known sanc­tu­ary for this deer, the Keibul Lam­jao Na­tional Park (klnp). While the world’s only float­ing na­tional park is spread over 40 sq km, the San­gai ter­ri­tory is re­stricted to only about 10 sq km, and it shrinks even fur­ther dur­ing the mon­soon as wa­ter lev­els rise. Ac­cord­ing to the prin­ci­pal chief con­ser­va­tor of forests, Bala Prasad, the 2013 cen­sus re­vealed that only 24 San­gais were added to the pop­u­la­tion since 2003,with the to­tal adding up to 204.

In­flated num­bers

How­ever, wildlife ex­perts con­test these num­bers, even as the In­ter­na­tional Union for Con­ser­va­tion of Na­ture (iucn) has put this deer un­der the red list of crit­i­cally en­dan­gered species. Dur­ing 1970s-80s, cen­sus was con­ducted us­ing mostly aerial sur­veys, while later sur­veys were ground-based. Po­lit­i­cal tur­moil in the re­gion and un­sta­ble habi­tats (shrink­ing of the float­ing phumdis) made it im­pos­si­ble to count their num­bers.Ace wildlife con­ser­va­tion­ist, M K Ran­jitsinh, also the chair­per­son of the Wildlife Trust of In­dia (wti), says, “It is bet­ter to as­sume a far lesser num­ber as cen­sus is not con­ducted ev­ery year in a sys­tem­atic way. “He was speak­ing at the In­sti­tute of Biore­sources and Sus­tain­able De­vel­op­ment, Im­phal.

Kh Shamungao, a re­tired pro­fes­sor of Zool­ogy and mem­ber of Ma­nipur’s State Board for Wildlife, Bio­di­ver­sity Strate­gies and Ac­tion Plan, says many of the San­gais pre­sumed to ex­ist are likely to be mul­ti­ple counts of a small num­ber, or ex­cess counts along with cer­tain hog deer. “A com­plex in­ter­play of sev­eral fac­tors in the field can re­sult in the fail­ure of the cen­sus method, usu­ally lead­ing to an over es­ti­ma­tion,” adds Shamungao.

With about 200 San­gais spread across zoos in Delhi, Ali­pore and Guwahati and breed­ing cen­tres in Ma­nipur, ex­perts say that lack of ge­netic di­ver­sity is largely con­tribut­ing to the slow growth of the pop­u­la­tion.The first pair of San­gai was “gifted” to Ali­pore Zoo in Kolkata in 1956,the same year when Keibul Lam­jao was ac­corded a “na­tional park” sta­tus. Ac­cord­ing to Ran­jitsinh, four deer were cap­tured in 1960s af­ter the first sur­vey in klnp. In 1987, a to­tal of 12 births were recorded which roughly makes it about 1.2 births a year. Cur­rently, the Na­tional Zo­o­log­i­cal Park, Delhi, and the As­sam State Zoo, Guwahati, main­tain the high­est stock of cap­tive San­gais, hous­ing 58 and 30 re­spec­tively.

Ge­netic over­sight

Shamungao shows a trend in which cap­tive pop­u­la­tion of the San­gai in all In­dian zoos ap­pears to in­crease ex­po­nen­tially till the 1980s, and af­ter that their num­bers be­gin to fall. He as­cribes two rea­sons for this. “First, over­crowd­ing the an­i­mals with low san­i­ta­tion in the en­clo­sures and, se­condly, a pos­si­ble ge­netic dis­or­der or de­te­ri­o­ra­tion due to long in­breed­ing with a small pop­u­la­tion,” says Shamungao. Ran­jitsinh cor­rob­o­rates this find­ing and says that some species of San­gai may have got mixed with other deer species. Sim­i­larly ,ver­te­brae ecol­o­gist and sci­en­tist with the Wildlife In­sti­tute of In­dia (wii), AJ T Johns­ingh, points out that an­i­mals for rein­tro­duc­tion should come only from the wild pop­u­la­tions in klnp, as the an­i­mals in cap­tiv­ity have re­duced ge­netic di­ver­sity. The wild ill-ef­fects of in­breed­ing can fur­ther cause the pop­u­la­tion of an an­i­mal to shrink. That’s why only 24 new San­gais were born dur­ing the last decade, ac­cord­ing to the for­est depart­ment’s cen­sus. “The slow rate of pop­u­la­tion growth, high rate of in­fant mor­tal­ity and de­creased sur­vival are the man­i­fes­ta­tion of ge­netic dis­or­ders. The in­breed­ing is com­monly as­so­ci­ated with a low­er­ing of vi­a­bil­ity, adapt­abil­ity and birth weight—a phe­nom­e­non known as in­breed­ing de­pres­sion,” says Shamungao.

Habi­tat de­gen­er­a­tion

The habi­tat of the San­gai is al­ready un­der stress. In 1983, the Ma­nipur gov­ern­ment built a bar­rage for a mul­ti­pur­pose power pro­ject on the con­flu­ence of the Im­phal river, Khuga river and its trib­u­tary, the Ungamel chan­nel, south of Lok­tak Lake.To main­tain the wa­ter and the power sup­ply,the author­i­ties raised the wa­ter height at th e reser­voir to 762.12 m. A study on Lok­tak lake by non­profit Kal­pavriksh found that klnp suf­fered ex­ten­sively as a re­sult of the raised wa­ter level—the park area was con­stantly in­un­dated by fre­quent flash floods, es­pe­cially dur­ing the mon­soon.

The study adds that the back­flow ef­fect of the Khuga river through the Ungamel chan­nel to­wards the south of klnp causes a sud­den wa­ter rise in the river dur­ing mon­soon which hits the na­tional park with great force. As a re­sult, the float­ing biomass or phumdi gets ripped apart and the loose veg­e­ta­tion drifts away. “This not only re­duces the veg­e­ta­tion cover in klnp ,but also en­dan­gers

MOIRANGTHAM RAN­JIT

Though of­fi­cial es­ti­mates say there are about 200 San­gais in the Keibul Lam­jao Na­tional Park, re­searchers say their num­bers could be even lower

Newspapers in English

Newspapers from India

© PressReader. All rights reserved.