Status profile - 2
Status, Conservation and Future of Saltwater Crocodiles in Orissa S K Kar and S K Patnaik

 

With the initiation of Government of India/FAO/UNDP Crocodile Conservation Project, the Forest Department, Government of Orissa implemented a scheme for conservation of saltwater or estuarine crocodiles (Crocodylus.porosus) along with two other crocodilian gharial (Gavialis gangeticus) and mugger crocodile (Crocodylus palustris). A Saltwater Crocodile Research and Conservation Centre was established at Dangmal in the heart of the Bhitarkanika Wildlife Sanctuary with the purpose of quickly multiplying the population using the `rear and release' technique to save this endangered reptile.

 

 Objective

The prime objectives of the saltwater crocodiles were (Kanungo, 1976) :

  1. To conserve the endangered saltwater crocodile species by providing adequate protection to its threatened habitat;

  2. To quickly build up its depleted wild population through large scale `rear and release' programme; and

  3. To conduct research on the ecology and biology of saltwater crocodiles.

  4. Later, to exploit the species (surplus population) through large-scale captive farming (during the second phase of the Project).

During last 24 years, maximum emphasis has been given to collection of eggs laid in wild from Bhitarkanika Sanctuary for safe hatchery incubation by simulating natural conditions, rearing the young ones with sound husbandry conditions and releasing juvenile crocodiles (over 1.0m in length) in the river system of the sanctuary, monitoring the released crocodiles, collecting relevant data on wild and captive populations besides study on socio-economic aspects of the local inhabitants and `man and crocodile' conflict etc. (Bustard, 1975; Daniel and Hussain, 1974; Kar 1978 & 1981).

 

 Rear and Release Programme

Due to successful implementation of this Conservation Research Management Programme, the depleted population of saltwater crocodiles have now gradually built up through large scale release of captive reared crocodiles into the wild as well as providing adequate protection to the mangrove habitat. 

 

During the last 24 years, 5274 eggs of C. porosus have been collected from the forest blocks of the sanctuary, out of which 2695 hatchling hatched (51.1%) and 2488 crocodiles survived (92.4%) at the Saltwater Crocodile Research and Conservation Centre, Dangmal. At present, about 300 crocodiles including one partially white (locally known as `Sankhua') female crocodile are being reared in captivity there.

 

Since the 1990s, the rear and release programme of C.porosus have been taken up on a very modest scale to keep alive husbandry and research techniques. At present over 40 clutches of eggs (more than 40 females are laying eggs including a few released crocodiles) are available inside the sanctuary but hardly a clutch or two (about 100 eggs) have been collected for project hatchery incubation.

 

 Restocking of Crocodiles

The wild population of saltwater crocodiles in Bhitarkanika was depleted to such an extent that the only way to restock was through release of captive reared young crocodiles (1.-0m size). The first releases back into the wild of 15 individuals took place in February to May 77 (Kar & Bustard, 1989), then 80 crocodiles during 1978 (Kar and Bustard, 1991) and this followed by subsequent releases of about 2000 young crocodiles in phased manner into the river systems of Bhitarkanika Sanctuary (Choudhary et at, 1996).

 

The average density of saltwater crocodiles (other than hatching) in Bhitarkanika was 0.87 individuals/km (Kar and Bustard, 1989 & 1991) during 1976-77 census (before release) but 1998 census indicated 5.0 individuals/km.

 

 Census of Crocodile Population

To ascertain the status of the crocodile population, the whole sanctuary including the peripheral areas have been surveyed covering all the river and creek systems during the peak winter months (December-January) regularly. According to the 1976-77 census (prior to release) indicated that there were 29 adults, six sub-adults and 61 juveniles in the entire Bhitarkanika sanctuary. In the last census in December 1998, a total of 672 crocodiles were counted, which included 150 hatchlings, 146 yearlings, 160 juveniles, 144 sub-adults and 72 adults (10 ft +).

 

The released crocodiles have been monitored regularly to (a) assess their survival in nature,; (b) study the habitat preference; and (c) record their movement, home range, seasonal migration and growth rate etc.

 

These annual operations indicate a close correlation between crocodile numbers (adults, sub-adults and juveniles) and the ecological health of the mangrove ecosystem. Considering the released population and annual natural recruitment, the survival of juveniles and sub-adults are not much encouraging due to several adverse factors, the major being biotic interference. 

 

 Crocodile Attacks on Humans

The saltwater crocodile is widely stated to be most dangerous species of crocodilian from the human standpoint (Neill, 19771). However, in our experience, instances of maneating have been greatly exaggerated (Bustard and Kar, 1982; Kar & Bustard, 1983). There have been 35 instances of attacks on human beings in the last 24 years (1975-76 to 1997-98) which includes 75% males. In 34 cases, large males of over 16 ft were responsible and in only one instance, a crocodile, 9 ft long, was involved for the killing of a human being. In 1988, within a span of few days, one crocodile of about 19 ft length was responsible for killing three persons who were fishing illegally at night in one of the creeks of the sanctuary. Later, the crocodile was netted and killed by the poachers (Kar & Padhi, 1992).

 

In Bhitarkanika Wildlife Sancturary, all ingredients for human attack exist, particularly the frequent human intrusion into the crocodile habitat illegally and crocodile population in the sanctuary including a couple of very large males (Kar & Bustard, 1989).

 

 Livestock Crocodile Conflict

Instances of attack on domestic livestock by saltwater crocodiles have been recorded from August 1975 to March 1998 inclusive. In all, 40 attacks involving buffaloes, bullocks, cows, calves and goats were recorded. All attacks/deaths reported were by large males of above 16 ft length. High-tide is usually essential to bring the crocodiles lying in wait in the water within striking distance of the animals grazing on the riverbank. 90% of the attacks occurred during the rainy season wherein riverbanks were flooded by high-tide/flood. The attacks all occurred at locations where the natural mangrove cover has been destroyed by the people. Ideally crocodiles and cattle should be separated and there should be no grazing in sanctuaries. The solution lies in maintaining a strip of undisturbed mangrove forests, at least 100m wide all along river/creek banks adjacent to cultivated land inside the sanctuary.

 

 Public Involvement

The crocodile conservation and research project not only ensures the conservation of this species but also, provides suitable job opportunities for a number of local inhabitants in various ways such as field attendant, research foresters, crocodile/sanctuary guards, husbandry attendants, tourist guides, fish suppliers for captive reared crocodiles and other such developmental and management work from time to time.

 

 Research priority

  1. Reintroduction of the young saltwater crocodiles in the Mahananadi estuary system and to study their survival movement and dispersal etc.,

  2. Study on `man-crocodile' conflict.

  3. Study on the carrying capacity of Crocodylus porosus in the Bhitarkanika Wildlife Sanctuary.

  4. Habitat features and population structure.

  5. Interpretations of various types of data collected during survey and census.

 Recommendations

  1. Encroachment on the mangrove habitat for rehabilitation, agriculture and prawn culture, etc. should be completely banned.

  2. Use of gill nets in the rivers, creeks and creek lets throughout the sanctuary should be strictly prohibited.

  3. Degraded mangrove forest should be restored by plantation and rigid protection. Moreover, at least 100m wide a strip of mangrove forest should be created all along rivers/creeks adjacent to cultivated land inside the sanctuary.

  4. Measures may be taken to eliminate man-crocodile conflict.

  5. Large-scale eco-development programme should be implemented on the outskrits of the sanctuary to minimize/reduce the pressure on mangrove forest by local people.

  6. Studies on the ecology of estuarine/saltwater crocodiles should be continued, considering the existing gap in the knowledge regarding various aspects of ecology of the species in Bhitarkanika and other distributional range in Orissa as well as in the entire country.

  7. Education and awareness programmes should be created among the local inhabitants to change their hostile attitude towards conservation of saltwater crocodiles and other wildlife species along with the threatened mangrove eco-system.

 Conclusion

Despite best efforts of `rearing and rehabilitating' this species, the future cannot be bright unless the sanctuary and the crocodiles are adequately protected and until large number of juvenile saltwater crocodiles attain breeding size and commence breeding in the wild. Besides, the deltaic areas of the Mahanadi river system, which was in recent past an ideal habitat for C.porosus (at present not a single crocodile is seen) should be restored and crocodiles should be rehabilitated into suitable protected creek systems. A long-term research programme on identified parameters should be taken up in this unique crocodile habitat with the funding support from Government of India.

 

 References


Bustard, HR (1974) - India : A preliminary survey on prospects of crocodile farming; FAO Rome (F.O.IND/71/033), pp 1-50. 

 

Bustard, HR and SK Kar, (1982) - Crocodile predation on man. Brit. J.Herpetol 6.222.223

 

Choudhury, Ch G; SK Patnaik, sk sinha, sk kar, cs kar and LAK Singh - The Wildlife Wealth of Orissa, Orissa Government Press, Cuttack. pp 1-85

 

Daniel, JC and H Hussain (1975)- A record of saltwater crocodile (Crocodylus porosus) J.Bombay nat. hist. Soc. 71 (2) : 309-312

 

Kanungo, BC (1976) - An integrated scheme for conservation of crocodiles in Orissa, with Management Plan for Satkosia Gorge and Bhitarkanika Sanctuary. Forest Department. Government of Orissa

 

Kar, SK (1978) - Saltwater crocodile resources in Orissa, Orissa Review, 35(3):50-52

 

Kar, SK (1981) - Studies on the saltwater crocodile Crocodylus porosus Scheider, Ph.D Thesis, Utkal University,Orissa, India.

 

Kar, Sk and HR Bustard (1983) - Saltwater crocodile attack on man. Biol. Conservation, London 25:337

 

Kar, SK and HR Bustard (1989) - Status of saltwater crocodile (Crocodylus porosus Schneider) in the Bhitarkanika Wildlife Sanctuary,Orissa, India, J. Bombay nat. Hist. Soc. 86 (2) : 141 _ 150.

 

Kar, SK and HR Bustard (1989) - Rehabilitation of saltwater crocodile (Crocodylus porosus Scheinder) in Bhitarkanika Wildlife Sanctuary, Orissa, India, J. Bombay nat. Hist. Soc., 88 (3) : 395-399

 

Kar, SK and GS Padhi (1992) - Present status of estuarine crocodiles (Crocodylus porosus Schneider) in Orissa, India. Ori-Forest (Quarterly magazine on Forestry & Wildlife _ Special Wildlife Number) Oct.Nov-1992, pp. 8-14

 

Neill,WT (1971) - The last of the ruling reptiles. Columbia Univ. Press, New York pp.1_ 486.

 

Singh, LAK (1996) - Cuttack. pp. 1-185.