The demographic studies on Sitana ponticeriana show that the species is abundant in Gabbur village. The lizards exhibited a diurnal variation in their activity pattern (basking, foraging, seeking refuge, etc.). They were active in the morning hours when air temperature was ≤ 33° C and census yielded maximum numbers (45 ± 2.19 in 18,748 sq m or ~ 1.9 ha area). The study provides a pilot index as well as a reliable and accurate methodology for population survey of the lizard. The pilot index is essential for any large scale monitoring project and population trend analysis in future

Ammanna, Veena H.

Dheeraj, K. V.

Gramapurohit, Narahari P.

Pandav, Bhagyarekha N.

Radder, Rajkumar S.

Saidapur, Srinivas K.

Shanbhag, Bhagyashri A.

English

Publications of the IAS Fellows

RESEARCH COMMUNICATIONS 
CURRENT SCIENCE, VOL. 85, NO. 9, 10 NOVEMBER 2003 1363 
are generally noticed in the areas that are structurally 
controlled. Keeping this aspect in mind, this line was 
finally selected to study the presence of VAMPs, if present. 
A bright spot is also clearly observed at ~ 3200 ms, which 
has the same polarity as that of the sea loor and may be 
marking the base of the free gas zone. On inspection of 
the stack section, we noticed only a few features resemb- 
ling the velocity pull-ups (like at ‘A’ and ‘B’; Figure 
2 b), but they are not associated with any pull-downs.  
 Preliminary studies over the WCMI indicate the abs nc  
of VAMP anomalies in the multichannel seismic data, 
which implies that the acoustic impedance across the hy-
drate bearing and the free-gas zone is not quite significa t. 
 
1. Kvenvolden, K. A., A primer on the geological occurrence of gas 
hydrates. In Gas Hydrates: Relevance to World Margin Stability 
and Climatic Change (eds Henriet, J. P. and Mienert, J.), Geologi-
cal Society of London, Special Publication, 1998, vol. 137, pp. 9–30. 
2. Hovland, M. and Judd, A. G., Sea Bed Pockmarks and Seepag s: 
Impact on Geology, Biology and the Marine Environment, Gran-
ham and Trotman, London, 1988, p. 293. 
3. Hyndmann, R. D. and Spence, G. D., A seismic study of methane 
hydrate marine bottom simulating reflectors. J. Geophys. Res., 1992, 
97, 6683–6698.  
4. Shipley, T. H. et al., Seismic evidence for widespread possible gas 
hydrate horizons on contine al slopes and rises. Am. Assoc. Pet. 
Geol. Bull., 1979, 63, 2204–2213. 
5. Scholl, D. W. and Cooper, A. K., VAMPs – possible hydrocarbon 
bearing structures in Berings Sea Basin. Am. Assoc. Pet. Geol. 
Bull., 1978, 62, 2481–2488. 
6. Cooper, A. K. et al., Hydrocarbon potential of Aleutian Basin, 
Bering Sea. Am. Assoc. Pet. Geol. Bull., 1979, 63 2070–2087. 
7. Rearic, D. M., Williams, S. R., Carlson, P. R. and Hall, R. K., Acoustic 
evidence for gas-charged sediment in the abyssal Aleutian Basin, 
Bering Sea, Alaska. USGS Open File Report, 1988, pp. 88–677. 
8. Scholl, D. W. and Hart, P. E., Velocity and amplitude struct r s 
on seismic reflection profiles – Possible massive gas hydrate de-
posits and underlying gas accumulations in the Bering Sea Basi . 
In Future of Energy Gases, USGS Prof. Pap. 1570 (ed. David, G. 
Howell), 1993. 
9. Minshull, T. and White, R., Sediment compaction and fluid migra-
tion in Makran Accretionary Prism. J. Geophys. Res., 1989, 74, 
7387–7402. 
10. Reddi, S. I., Thakur, N. K., Ashalatha, B. and Sain, K., Reprocess-
ing multichannel seismic data of the ONGCL for gas hydrate 
exploration in the offshore Goa. NGRI Technical Report, 2001. 
11. Karisiddaih, S. V., Veerayya, M., Vora, K. H. and Wagle, B. G., 
Gas-charged sediments on the inner continental shelf off western 
India. Mar. Geol., 1993, 110, 143–152. 
12. Gupta, H. K. et al., Analysis of single channel seismic data along 
the continental margin of India for gas hydrates. NGRI Technical 
Report No. -98-Lithos-221, 1998. 
13. Rao, Y. H., Subramanyam, C., Rastogi, A. and Deka, B., Anomalous 
features related to gas/gas hydrate occurrences along the western 
continental margins of India, Geo-Mar. Lett., 2001, 21, 1–8. 
 
ACKNOWLEDGEMENTS. We thank Dr V. P. Dimri, Director, NGRI 
for his kind consent to publish this work. N.S. acknowledges the Coun-
cil of Scientific and Industrial Research for fellowship assistance.  
We also thank the reviewers for providing suggestions to improve the 
manuscript. 
 
Received 24 February 2003; revised accepted 24 July 2003 
 
Demography of fan-throated lizard, 
Sitana ponticeriana (Cuvier) in a  
cotton field in Dharwad District  
of Karnataka State, India 
Bhagyashri A. Shanbhag*, Rajkumar S. Radder,  
Narahari P. Gramapurohit, K. V. Dheeraj,  
Veena H. Ammanna, Bhagyarekha N. Pandav  
and Srinivas K. Saidapur 
Department of Zoology, Karnatak University, Dharwad 580 003, India 
The demographic studies on Sitana ponticeriana show 
that the species is abundant in Gabbur village. The 
lizards exhibited a diurnal variation in their activity 
pattern (basking, foraging, seeking refuge, etc.). They 
were active in the morning hours when air tempera-
ture was £ 33°C and census yielded maximum nu-
bers (45 ± 2.19 in 18,748 sq m or ~ 1.9 ha area). The 
study provides a pilot index as well as a reliable and 
accurate methodology for population survey of the 
lizard. The pilot index is essential for any large scale 
monitoring project and population trend analysis in 
future. 
THE general distribution of Indian reptiles is well known1. 
It is believed that they are sparsely distributed and some 
species are endangered though in reality they are still 
abundant in a given area of their distribution. Hence, it is 
necessary to monitor populations of Indian reptiles in the 
wild by surveying a large number of sites periodically 
during specific periods of time, based on their activity 
pattern and breeding season. This will help in assessing 
changes in the species abundance. Such data represented 
as indices, using the first/pilot year as a base year, are 
essential for assessing the present status and also for 
lon -term monitoring of the population dynamics2,3. The 
findings of such studies will help in evolving conserva-
tion and policy-making strategies. 
 Sitana ponticeriana is a medium-sized (adult snout vent 
length, 5–8 cm), ground-dwelling agamid lizard (Figure 1) 
distributed throughout India, preferably in dry and more 
or less open country4. They are diurnal and insectivorous. 
The body of these lizards is brown above with a series of 
dark brown, black-margined, rhomboidal, vertebral spots 
on the back. The throat fan in males is brilliantly coloured 
with red, blue and dark shades during the breeding months. 
These lizards run with a considerable speed and on the 
approach of danger dash away with tail tip erect, until 
they find refuge in some bushes or crevices in the ground. 
When running quickly they often adopt bi-pedal mode of 
locomotion. These lizards are oviparous, polyautochronic, 
multi-clutched and breed from May to August in Southern 
India5–7. 
*For correspondence. (e-mail: bhagyashri_shanbhag@hotmail.com) 
RESEARCH COMMUNICATIONS 
CURRENT SCIENCE, VOL. 85, NO. 9, 10 NOVEMBER 2003 1364 
 To the best of our knowledge, no baseline data on the 
population size in a given area are available for any Indian 
lizard species including S. ponticeriana. During our routine 
field work, we encountered S. ponticeriana at many places 
in Karnataka (Figure 2) that include the surrounding  
areas of Bijapur, Gadag, Hospet, Gabbur village (near 
Hubli, Dharwad distr ct), Chitradurga and Hassan. In 
Hospet and Chitradurga areas the lizards were spotted in 
the hilly and rocky areas beset with large boulders while 
in the other places they were found in open fields. In 
Gadag and Gabbur area they were found in the cotton 
fields, sites convenient for survey work. The present 
study was undertaken to (i) make a status survey of the 
population of S. ponticeriana in the cotton fields at Gabbur, 
(ii) to develop a standardized protocol for monitoring these 
lizards, and (iii) to provide a base index for future moni-
toring studies. 
 The present field survey was confined to a cotton field 
near Gabbur village 25 km away from Dharwad (15°17¢N, 
75°3¢E). The habitat in the study area is characterized by 
its black soil with several crevices, burrows and wide 
cracks that serve as abode for the lizards. Harvested cotton 
plants, scanty grass and some bushes around the edges of 
cotton field dominated the vegetation. 
 The study area was arbitrarily div de  into two parts 
and 28 transects using naturally available topographical 
marks. The first half of the study area had 14 transects, 
each measuring 6.09 m in width and 97.54 m in length. 
The second half of the study area lso had 14 transects, 
each measuring 6.09 m W × 121.92 m L. The combined 
total area was thus 18,748 sq m (~ 1.9 ha). The transect 
boundaries were marked using coloured cloth flags num-
bered serially. 
 The surveys were conducted on three different days 
(27 April, 10 May and 20 May 2003). We walked in a 
given transect from one end to the other and reco ded the 
sex and number of S. ponticeriana. Both visual spotting 
and combing methods were used. The surveying was done 
thrice in a day, i.e. btween 0800 and 1030 h, 1400 and 
1530 h and 1630 and 1800 h. Each transect was surveyed 
back and forth on all occasions. Thus, each transe t was 
surveyed 18 times. To avoid overestimation of the lizard 
population due to back and forth transect sampling, the 
population size was derived by multiplying the observed 
counts (mi) with 0.5, the common weight (Wi) factor for 
each time point8. 
 Variation in the number of male and female lizards 
sighted, and total number of lizards recorded at different 
times of the day were analysed separately by c2-test  
(G test and R × C model). 
 Back and forth survey of a given transect took ~ 45min. 
The maximum number of adult S. ponticeriana recorded 
on three different days was consistent, i.e. 41, 47 and 48 
respectively, in 18,748 sq m or 1.9 ha area. There was no 
significant difference in the number of males and females 
 
Figure 1. S. ponticeriana in the cotton field at Gabbur village. , Male 
displaying its secondary sexual features; b, A gravid female basking in 
the open. 
 
 
 
Figure 2. Map of Karnataka and places where S. ponticeriana was 
spotted. 
 
 
Figure 3. Number of male and female S. ponticeriana recorded on 
three different days (mean ± SD) and plotted in relation to air tempera-
ture and time of survey. Survey area = 1.9 ha. 
 
RESEARCH COMMUNICATIONS 
CURRENT SCIENCE, VOL. 85, NO. 9, 10 NOVEMBER 2003 1365 
(G test c2df 1 = 0.004, P > 0.05, Figure 3). The average 
number of lizards recorded during the morning sessions 
was 45 and hence amounted to one lizard/416 sq m area. 
 On all occasions the total number of lizards sighted 
varied greatly with respect to the time of the day (c2df 2 = 
5.99, P < 0.05). Maximum number of lizards was sighted 
during morning hours when the average air temperature 
was low (32.08°C ± 1°C, Figure 3). As the day progres-
sed, by afternoon a few lizards could be sighted in each 
transect (Figure 3). In the afternoon the lizards were 
found either in shady areas or inside the burrows where 
the air temperature was 34°C–35.5°C while in the open 
field it was 40.5°C ± 1°C (Figure 3). In the evning hours 
the total number of lizards sighted was greater compared 
to that of the afternoon survey. Yet, the number of lizards 
sighted during evening was less than that recorded in the 
morning hours (Figure 3). 
 During morning hours S. ponticeriana were very active 
and generally engaged in basking or feeding. With the 
rise in air temperature by noon they confined themselves 
to shady areas or natural burrows and became less active. 
During evening once again they appeared in the ope  
field but exhibited only a moderate activity. The females 
were invariably gravid and showed bulged abdomen beset 
with oviductal eggs. The males exhibited gorgeous fan 
throats. Thus, the specimens were adults and in breeding 
condition. No juveniles were encountered. 
 Despite its wide distribution in India, demographic stu-
dies on the fan-throated lizards are lacking. The present 
demographic work though restricted to a cotton field  
reveals many interesting aspects of the lizard biology. It 
shows that survey of any lizard species is best carried out 
during appropriate weather conditions and time of the 
day/month based on the knowledge of its seasonal/daily 
activity patterns. Since reproduction-related events in 
S. ponticeriana occur between April and Maywhen they 
come out of their shelters in large numbers in search of mates 
and suitable sites for egg-laying and so on, the present 
status survey was undertaken in these months. Indeed, the 
study shows that during the favourable part of the day 
(morning hours) the lizards engage themselves in various 
breeding-related activities like mate searching, sexual dis-
play, territory guarding, etc. 
 Different methods are employed for the estimation of 
population size in reptiles9,10. Of these, we find that vis-
ual spotting combined with combing is a good method for 
demographic studies on S. ponticeriana,  fossorial lizard. 
The census data based on 18 surveys done on three dif-
ferent days, with 10 to 12-day interval in the same field 
gave consistent results, thereby suggesting the accuracy 
and reliability of the transect sampling method. Likewise, 
the census data were remarkably consistent with respect 
to the time of the day. The number of lizards recorded in 
the morning hours was always the greatest. Apparently to 
arrive at a realistic population size of the S. ponticeriana 
the survey should be undertaken before noon hours. Dur-
ing this time, the lizards are found foraging or basking in 
the open and males displaying their secondary sexual 
characteristics. Since the maximum number recorded was 
clos  to the mean value, the latter serves as a good indi-
cator of population size of S. ponticeriana in a given area, 
as also reported recently for the Netherlands lizar 3. 
 The activity pattern in reptiles may vary with the species 
or ecological conditions11,12. Reptiles being ectothermic, 
gen rally exhibit intense activity pattern when the ther-
mal microclimate is favourable. In addition, prey avail-
ability also governs their activity pattern. The prsent 
findings clearly show that activities of S. p nticeriana 
mainly depend upon the air temperature. The number of 
lizards that could be sighted was more with rise in the 
morning air temperature. Mean number of lizards obser-
ved before noon was distinctly higher than that of after-
noon/evening sightings. During afternoon due to a rise in 
the air temperature the lizards sought shelter under cre-
vices and bushes and were difficult to sight. Although 
evening temperature was comparable to that in the morn-
ing, the lower number of lizards sighted in the eve ing 
suggests the possible influence of other unknown factors 
or diurnal activity pattern, if any. A variation in the num-
ber of lizards that could be spotted at different times of 
the day indicates that knowledge of the activity pattern  
of a g ven species is crucial for demographic studies. Evi-
dently, the best time to conduct population survey of  
S. ponticeriana is early morning hours when they emerge 
out of their abodes and are highly active. Based on the 
pilot study (first year data) no major conclusions an be 
drawn with regard to the population trend. However, the 
pil t study provides a base index and allows future popu-
lation trend analysis over a period of time.  
 
1. Tikader, B. K. and Sharma, R. C., Indian fan-throated lizard  
Sitana ponticeriana Cuvier 1884. In Handbook of Indian Lizards 
(ed. Director, Zoological Survey of India), ZSI, Culcutta, 1992, 
pp. 83–84. 
2. Zuiderwijk, A. and Smit, G., Reptielen monitoring 1990–1992 
(Reptile monitoring 1990–1992, in Dutch). Herpetogeografische 
Dienst ‘Lacerta’, Nieuwsbrief 1993, p. 9. 
3. Zuiderwijk, A., Groenveld, A. and Smit, G., Monitoring of reptiles 
in the Netherlands. In Monitoring of Reptiles in the Netherlands 
(eds Miaud, C. and Guyetant, R.), Le Bourget du Lac., France, 
1998, pp. 455–462. 
4. Daniel, J. C., Fan-throated lizard Sitana ponticeriana Cuvier. In 
The Book of Indian reptiles, Bombay Natural History Society, Bombay, 
1983, pp. 45. 
5. Subba Rao, M. V. and Rajabai, B. S., Reproduction in the ground 
lizard, Sitana ponticeriana and the garden lizard, Calotes nemo-
ricola. Br. J. Herpetol., 1972, 4, 245–251. 
6. Shanbhag, B. A., Reproductive biology of Indian Reptiles. PINSA, 
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Sci., 2003, 85, 101–103. 
8. Pannekoek, J. and Strien, A. V., TRIM 3 manual (Trends and indi-
ces for monitoring data). St tistics Netherlands, 2001, 102, 1–57. 
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CURRENT SCIENCE, VOL. 85, NO. 9, 10 NOVEMBER 2003 1366 
 
9. Dunham A. E., Morin, P. J. and Wilbur, H. M., Methods for the 
study of reptile populations. In Biology of Reptilia. Ecology B,  
Defense and Life history (eds Gans, C. and Huey, R. B.), Alan R. Liss,
New York, 1988, pp. 333–385. 
10. Sutherland, W. J., Ecological Census Techniques, A Handbook, 
Cambridge University Press, Cambridge, UK, 1996. 
11. Ellinger, N., Schlatte, G., Jerome, N. and Hodl, W., Habitat use 
activity patterns of the neotropical arboreal lizard Tropidurus
(= Uracentron) azureus werneri (Tropiduridae). J. Herpetol., 2001, 
35, 395–402. 
12. Grant, B. W. and Dunham, A. E., Thermally imposed time con-
straints on the activity of the desert lizard Sceloporus merriami. 
Ecology, 1988, 69, 167–176. 
 
 
ACKNOWLEDGEMENTS. This work was supported by a grant from 
UGC (SAP II), New Delhi. RSR was supported by CSIR, New Delhi as 
a Research Associate. We thank Drs A. Zuiderwijk and A. van Strien, 
Department of Herpetology, University of Amsterdam, The Nether-
lands for providing TRIM statistical package for data analysis. 
 
 
Re eived 19 June 2003; revised accepted 15 July 2003 
 


Demography of fan-throated lizard, Sitana ponticeriana (Cuvier) in a cotton field in Dharwad district of Karnataka state, India

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Demography of fan-throated lizard, Sitana ponticeriana (Cuvier) in a cotton field in Dharwad district of Karnataka state, India

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