Status profile - 12
Survey of Gharial in National Chambal Sanctuary - 1993-97
RK Sharma 

The Chambal river was declared a Gharial Sanctuary (location : 250 30`N - 260 52`N and 760.28`- 7900'E) in 1978-79 under the Crocodile Project with the aim to provide a fully protected habitat for the conservation and propagation of the gharial and other acquatic animals. An area of about 425km of the Chambal river from Pali (Chambal-Parvati confluence) to Bhare (Chambal-Yamuna confluence) is now under the management of the National Chambal Sanctuary. which forms boundary between Rajasthan and Madhya Pradesh, and between Madhya Pradesh and Uttar Pradesh. The river finally joins the Yamuna near Etawah in Uttar Pradesh. (See Figure 10)

 

For proper management of a river it is very important to know its existing fauna. In order to assess the role of environmental changes in the distribution of species regular surveys and census of the gharial population in the National Chambal Sanctuary have been conducted since 1984 (1984-91 and 1993-98).

 

 Methodology

As a follow-up to the earlier surveys conducted in 1984-1991
the entire stretch of the Chambal river under sanctuary status was annually surveyed in the winters (November _ February) during the period 1993-1998, for gharial, mugger and other aquatic vertclimates animals. The surveys were conducted on a boat fitted with an out-board motor (40 HP) and also on foot. Field binocular was used for recording numbers and approximate size of the animals. All sightings were recorded on the field map sheets. Informal discussions were held with persons directly or indirectly involved in the affairs of sanctuary area. Table I below presents gharial counts made in the study area.

 

 Observations and Findings

1. In the 1993 survey, a total of 898 gharials in all sizes were sighted with a mean density

    of 2.11 gharial per km. Out of these, 186 were adults (20.71%), 305 sub-adults

   (33.96%), 141 hatchlings (15.70%) and 266 yearlings (29.62%).

 

2. The total number of gharials sighted in the 1994 survey was 1108 with a mean density of

    2.6

 

Table – 1. Status and distribution of Gharial in National Chambal Sanctuary during 1993-97.

 

 

Table 2. Nesting date of National Chambal Sanctuary during 1993-97:

 

 

gharial per km. The age-group distribution was - adult 18.23%. sub-adult 37.72%, hatchling 15.52% and yearling 28.51%.

 

3. During the 1995-96 survey, 1214 gharial with a mean density of 2.8 gharial per km were counted. The age-group distribution was adult 17.48%, sub-adult 36.65%, hatchling 15.56% and yearlings 30.31 %.

 

4. In 1996-97, the total number of gharials sighted in the survey was 1242, with a mean density of 2.9 gharial per km. The age-group distribution was adult 18.19%, sub-adults 36.95%, hatchling 18.67% and yearling 25.92%.

 

Gharial nest survey 1993 - 1997

 

In addition to the annual population surveys, summer surveys were also conducted to locate gharial and mugger nests in the Chambal river (Table2)

 

 CONCLUSION

During 1993-1997, an increasing trend in the population dnsity of gharial in the National Chambal Sanctuary can be marked. Although, the increase is not significant, it seems to be satisfactory. The percentage of yearlings in 1995-96 is high (30.31%) because about 80 yearlings were released from the Deori gharial rearing centre prior to the survey. From the nesting survey figures, it is also apparent that between 1993 and 1997, 17 new gharial females joined the breeding group. And though a large number of nests are located during the summer months, only a small percentage of hatchlings are seen the following winter. This could be attributed to the nest predation in the wild, dispersal and loss of hatchlings following hatching due to predation, mortality and the monsoon floods. It is, however, important to emphasize that such annual gharial nesting and population surveys are essential to determine the well being of perhaps one of the world's best crocodile rehabilitation projects.
 

 References

Khan Z (1983) - Son gharial sanctuary : Summary plan and management. Forest Department, Madhya Pradesh.

 

Sharma, RK, Sanjay Sharma and R Mathur (1995) - Wildlife Survey in Madhya Pradesh _ II, Survey Report on Ken gharial sanctuary, Journal of Freshwater Biology, 7(1) : pp. 59-62.

 

Sharma RK and Sanjay Sharma (1997) - Wetland faunal survey of Son gharial sanctuary in Madhya Pradesh. The Indian Forester, Vol. 123, No. 10. pp.952-957.

 

Sharma RK and R Mathur (1997) - Biodiversity in national Chambal Sanctuary, Status and stretegies for management. Annual Report to the Madhya Pradesdh Council of Science and Technology, Bhopal, mimeo 30 p.