Lake 2010: Wetlands, Biodiversity and Climate Change

22nd-24th December 2010 Page 1

ANURAN AMPHIBIAN DIVERSITY, DISTRIBUTION AND HABITAT

USE IN DHARWAD

Rajendra M. Pattar*1, Vijaykumar A. Kudari 2 and Ravishankar D. Kanamadi 3

* Author for correspondence

1Assistant Professor in Zoology, Kittel Science College, Dharwad, 580001

2 and 3Department of Zoology Karnatak University, Dharwad, 580003

Karnataka State, India

E-mail: raju_pathar@yahoo.com

ABSTRACT:

The distribution of anuran amphibians in Dharwad area has been studied. A total of 13 species were

recorded in the present study. The absence of Uperedon systoma was noticed, which may be attributed to its rare

occurrence or reduction in its population size. The population density of Hoplobatrachus tigerinus has reduced

drastically in comparison with earlier reports. The Kapila pond and puddles around Kelageri tank form potential

breeding grounds for 11 species, suggesting their species richness. The species Philautus variabilis is expanding its

distribution.

The present study reveals that by and large the number of anuran species that were found earlier have been

retained in Dharwad area in spite of destruction of habitat structure. However, the density of population of few

species has reduced. Geographical Information System (GIS) was also made use, as it allows the spatial and

temporal analysis of the features of interest and helps in solving the ecological problems. In this current study, an

attempt is made for mapping the potential breeding grounds to give a base line data for further research.

Key words: Anurans, diversity, GIS, breeding ground, Dharwad

INTRODUCTION:

Monitoring and mapping of biological recourses is a major concern from the conservation perspective as the

depletion of biodiversity is an irreversible change. Studies on amphibians of Dharwad (Kanamadi and Saidapur,

1981, Saidapur and Kanamadi, 1982; Kanamadi and Hiremath, 1989, 1990; Kanamadi et al., 1992, 1993, 1994,

1995, 1996; Kadadevaru and Kanamadi; 2001) indicate that it is rich in anuran species. Due to rapid urbanization

during last two decades there is a considerable change in the habitat areas of anurans. In the course of urbanization,

there is diversion in inflow of water and conversion of many tanks into layouts. Kudari and Kanamadi (2008)

suggested that the existing water bodies have reached eutrohic state. The present study was undertaken to assess the

impact of urbanization on anuran species, if any. The investigation includes the current status of anuran species

diversity, their habitat use and mapping of breeding grounds.

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MATERIALS AND METHODS:

Dharwad (15º 17΄ N 75 º 3΄ E ) is situated on the edge of Western Ghats and is hilly area spread over

seven small hills at an average altitude of 750 meters above the sea level. It is in between two distinct geographical

divisions i.e. Malenadu (hilly, forest land with red soil) and Belawalnadu (Deccan plains with black soil). Anuran

habitats of Dharwad were surveyed. The potentiality of breeding activity was determined based on the richness of

advertisement calls. Based on breeding activity to monitor, fifteen water bodies were selected for the present study.

The field studies were carried out for a period of two years (2009 and 2010) during monsoon season. The species

were identified based on the publications (Kanamadi and Saidapur, 1981; Saidapur and Kanamadi 1982; Kanamadi

and Hiremath, 1989, 1990; Kanamadi et. al., (1992, 1993, 1994, 1995, and 1996) and bioacoustics. The species were

further confirmed by using standard keys (Daniel, 1963; Daniels, 1975) and using sound ruler software by

comparing the oscillograms with published data. Land use dynamics was analyzed for study area by using Survey of

India toposheet which covers Dharwad town with base layers such as region’s boundary, and vegetation types. The

digitization of study area was done by using toposheets, Google earth free software available on net and Map Info

Professional 8.0 software.

RESULTS AND DISCUSSIONS:

The number of anuran species found in the study area in comparison to previous studies summarized in

Table 1. In the present study, a total of 13 species belonging to 11 genera were recorded. Kanamadi and Hiremath

(1989) reported the presence of 13 anuran species (table-2). Later Kanamadi et al., (1996) added one more species to

this list i.e., Philautus variabilis. During two years of our study 13 species were recorded except Uperedon systoma.

The absence of this species might be due to reduction in its population size or its rare occurrence.

Microhyla ornata, Euphlyctis cyanophlyctis, Limnonectes limnocharis, Polypedatus maculatus and Bufo

melanostictus are widely distributed in Dharwad area which is similar to the observations of Kanamadi and

Hiremath (1989) with respect to the species E. cyanophlyctis, B. melanostictus and P. maculatus.

Hoplobatrachus tigerinus was reported to be widely distributed (Kanamdi and Hiremath, 1989). The present

study shows that its population has drastically reduced and was recorded in 11 water bodies out of 15 surveyed

(table-1). Even in these 11 water bodies the population of this species was not thick and a maximum of five

amplected pairs were recorded at the peak of breeding activity. This reduction in population size in comparison to

previous reports might be due to urbanization which has directly resulted in destruction of breeding grounds (fig-1

and 2). Many at times due to heavy premonsoon rains the breeding may occur earlier and development activity begin

but further these temporary water bodies may not support complete development which might have resulted in

reduction in the population size during successive years.

The population density of Rana crassa was very thin around Dharwad (Kanamdi et al., 1992). In the

present study it was found only in three water bodies, which supports the observations reported earlier (Kanamadi,

et.al., 1992). Kaloula taprobanica was found only in two water bodies, which appears to be very rare in occurrence.

However there are no reports regarding its population densities earlier. Microhyla ornata and L. limnocharis are

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widely distributed and commonly found in all the water bodies and their population appears to be very thick. This

suggests that these species have quickly adapted to changing habitat structure, so that their breeding activity appears

to be normal even now. Microhyla rubra and Sphaerotheca breviceps were found in 10 and 12 water bodies

respectively and their population was scarce in comparison to M. ornata and L. limnocharis which means that they

are yet to adjust to the changing habitat structure.

Philautus variabilis exhibits direct development (Kanamadi et al., 1996) and is found in Dharwad area. Our survey

from 1996 to till date indicates that it is expanding its distribution around Dharwad year after year. This shows that

the species has greater adaptability towards changing habitat structure.

11 anuran species occur in two water bodies i.e. Kapila pond and Kelageri tank (table-1) which exhibits

species richness. This suggests that the breeding grounds for these species have been preserved even after

construction of new layouts around these ponds. Kapila pond over the years though decreased in its size has retained

its potentiality for the anuran breeding activity. The present study suggests that by and large the number of anuran

species that were found earlier have been retained in Dharwad area inspite of destruction of habitat structure.

However, the density of population of few species has reduced. Further there is a need for quantitative assessment.

ACKNOWLEDGEMENTS:

The authors acknowledge the financial help received from UGC, New Delhi in the form of Minor

Research Project and authorities of Department of Zoology, Kittel Science College, Dharwad for the infrastructural

help. Special thanks are due to Prof. A. D. Kamath of C.S.Bembalgi College, Ramdurg for the help rendered in the

current study.

REFERENCES:

Daniel, J.C. (1963). Field guide to the amphibians of Western India. J Bombay Nat. Hist. Soci. 60:415-438.

Daniels, R.J.R. (1997b). A field guide to the Frogs and toads of the Western Ghats: India. Cobra 28, 1 -24.

Kanamadi R D and C R Hiremath (1989) Anuran amphibian fauna of Dharwad; J. Karnatak Univ. Sci.33 8–12

Kanamadi, R. D. (1996). Acoustic communication in some Indian anurans: A review. Zoos' print. XI (8), 26-35.

Kanamadi, R. D., Hiremath, C. R. and H. Schneider (1993). The advertisement call of South Indian frog

Ramanella variegata (microhylidae). J.Herpetol.,27:2lS-2l9.

Kanamadi, R. D., Hiremath, C. R. and H. Schneider (1994). Advertisement call of two anuran amphibians,

Rana tigrina and Tomopterna breviceps. J . Bio.Sci 19, 75-80.

Kanamadi, R. D., Hiremath, C. R. and H. Schneider,11. (1995). Vocalization and lerriloriality of the Indian

frog, Rana limnocharia. Pine. naliiSci. Acad. B59, 489- 500.

Kanamadi, R. D., Hiremath, C. R. and H. Schneider (1992). Vocalization and breeding period In the South

Indian tropical frog, Rana crassa

Kanamadi, R.D. and C.R. Hiremath, (1990). Vocalization and breeding period in the burrowing from

Tomopterna breviceps. Environ. Ecol. 8, 1055-1056.

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Kanamadi, R.D. and S.K. Saidapur, (1981). Effect of short- term treatment of methallibure (ICI.33828) on the

testis and thumb pad of the toad Bufo melanostictus. Curr.Sci.50., 623-624.

Kanamadi,R.D., Hiremath,C.R. and H. Schneider. (1994). Advertisement calls of two anuran amphibians, Rana

tigrina and Tomopterna breviceps. J. Biosci. 10, 75-80.

Kanamadi,R.D., Hiremath,C.R. and H. Schneider. (1994). Courtship, Amplexus and advertisement call of tree

frog Microhyla rubra. Curr. Sci. 66, 5-11.

Kanamadi,R.D., Hiremath,C.R. and H. Schneider, (1995). Vocalization of tropical Indian toads Bufo

melanostictus and Bufo fergusonii. J. Adv. Zool. 16, 5-11.

Kanamadi,R.D., Nandihal,H.N., Saidapur,S.K. and N.S. Patil, (1996). Fecundity and parental care in the frog,

Philautus variabilis. J.Adv. Zool. 17, 68-70.

Kudari, V.A. and R.D. Kanamadi. (2008). Impact of changed trophic status on the zooplankton composition in

six water bodies of Dharwad district, Karnataka State (South India). Environmental Monitoring and

Assessment: 144(1-3): 301-313.

Patil, N.S. and R.D. Kanamadi, (1997). Direct development in the rhacophorid frog, Philautus variabilis

(Gunter). Curr. Sci. 73, 697-701. Daniels, R.J.R. (1997a). A field guide to the frogs and toads of the

Western Ghats: India. Cobra 27, 1-25.

Saidapur,S.K. and R.D. Kanamadi (1982). A comparative study of spermatogenetic cycle in Rana cyanophlyctis

(Schn.). and R .tigrina (Daud.). Biol.Bull.India, 4, 110-113.

Table-1. The current composition of Anurans and their habitat use in Dharwad

+ stands for the presence of the species - stands for absence of the species

Locality

Kel

geri

ta

nk

Sad

anke

re

tan

k

Kap

ila

po

nd

MB

A p

on

d

Sta

diu

m

po

nd

Ett

ing

udd

a ta

nk

Ag

ril.

Q

uar

ter

tan

k

Tap

ovan

p

on

d

Nav

od

aya

po

nd

Hig

hw

ay

po

nd

Sav

adat

ti

po

nd

Rai

lway

b

rid

ge t

ank

So

man

ath

tan

k

Nu

gg

iker

i ta

nk

Nav

alu

r ta

nk

1 Hoplobatrachus

tigerinus + + + + + + + + + + + + + + +

2 Rana crassa + - - - - - - - - - - + + - -

3 Microhyla

ornata + + + + + + + + + + + + + + +

4 Microhyla rubra + - + + - + + + - + + + + + +

5 Ramanella

variegata + - + + + + + + + + - + + + -

6 Euphlyctis

cyanoplyctis + + + + + + + + + + + + + + +

7 Limnonectes

limnocharis + + + + + + + + + + + + + + +

8 Polypedates

maculatus + + + + + + + + + + + + + + +

9 Philautus

variabilis - - + - - - - - - - - - - - -

10 Sphaerotheca

breviceps + - + - + + + - + + + + + -

11 Bufo fergusonii + - + - + + + - + + + + + + +

12 Bufo

melanostictus + + + + + + + + + + + + + + +

13 Kaloula

taprobanica - - + - + - - - - - - - - - -

Table-2. The comparative view of Anuran diversity

Note: 2010* = current investigation, 1989*= Kanamadi and Hiremath, and 1996*= Kanamadi et al.,

+ stands for the presence of the species - stands for absence of the species

Sl.no Species 2010*

1989 *

and

1996*

1 Hoplobatrachus tigerinus + +

2 Rana crassa + +

3 Microhyla ornata + +

4 Microhyla rubra + +

5 Ramanella variegata + +

6 Euphlyctis cyanoplyctis + +

7 Limnonectes limnocharis + +

8 Polypedates maculatus + +

9 Philautus variabilis + +

10 Sphaerotheca breviceps + +

11 Bufo fergusonii + +

12 Bufo melanostictus + +

13 Kaloula taprobanica + +

14 Uperdon systoma - +

13 14