Vol. 7, pp. 87-92

Asiatic Herpetological Research

1997

Population Dynamics and Growth in a Natural Population ofLimnonectes limnocharis ( Anura: Ranidae)
ASHIS. K. MOHANTY

1,NlNA SlNGH 2 AND SUSHIL K. DUTTA 2/College of Basic Sciences and Humanities, Orissa University of Agriculture and Technology. Bhubaneswar,Orissa, India; IDepartment of Zoology, Utkal University, Bhubaneswar-751004, Orissa, India

Abstract. -The study is based on measurement of specimen, collected from nature over a period of 12 months,

during 1987-88. Based on the size, the juveniles, mature males and gravid females were divided into various sizegroups. Except the juveniles, the female size groups were comparable with the males. In addition, the females
are comparatively larger than the males of the same age group.

The availability of various size groups during

different months of a year, is attributed to the continuous growth of the species in natural population

Ke\ words: Anura. Limnonectes limnocharis. population, growth.

Introduction

ResultsThe

Out of 962 specimens sampled, the lowest (43) andthe highest (110) captures were during March andfirst available information on growth study ofanurans was by Wright (1914), who analyzed growth

pattern of Rana pipiens and Rami catesbeiana.
then,several other studies

1936:

1925;

Force.

1933;(Wright.

Hamilton.

Since

1920; Flower,1934;

1955;

Raney and Ingram, 1941; Cowan, 1941; Raney andLachner,

1947;

Wilson,

1950:

Ting.

1951:

Ryan,1953; Fitch, 1956a; 1956b; Jameson. 1956; Martof,1956;

Cohen and Howard. 1958: Durham and Ben-nett,

1963; Schroeder and Baskett, 1968) reported thegrowth pattern of anurans either in captivity or in natTurner
ural environment by analyzing individuals.
(1960) reviewed

allthe above literature

on anuran

growth and since then additional data has become
available for Bufo hemiophrys (Breckenridge andTester.

1961),

arvalis (van Gelder.

1961).

Rana erythraea (Brown and Alcala,1970).

Rana

Rana
1973; van Gelder and Oomen.

Rana sylvatica (Bellis,septentrionalis (Hedeen.

1970),1972), Bufo boreas(Lillywhite et al., 1973) and Bufo woodhousei fowleri(Clarke. 1974). All the above studies (except Brownand Alcala, 1970) deal with anurans from temperatezones. The present study is the second one for any
Indian anurans.

The first study was conducted by

Sahoo 1991 on Bufo melanostictus.
()

Materials and Methods

A total of 962 specimens (388 males. 267 females and307 juveniles were collected over a period of 12months, from a perennial pond near village Chakeisani,

Bhubaneswar. India.

mm

September respectively. The ratio of male to female
for each month

Specimens ranging from

17.0-38.0
snout-vent length (SVL). were sexed
and the rest were treated as juveniles.

indicated more males than females, except duringmonth of February, when the number of males
were slightly less than that of the females. Cumulative ratio was also indicative of more males. The popthe

dynamics of juveniles indicated maximum
Further,(53) during the month of June (Table 1).
fromdecreased
drastically
population
juvenile
ulationDecember through January and no juveniles were colThe low population density of juveniles during December andlected during February and March.

Januaryand non-availability during February andMarchisassociatedwith

non-breeding

season,because, basically the species breeds during monsoon
period (June-August) when the number of juveniles in
the natural population is more than non-breeding

months.

To analyze the growth pattern in natural population, size range of juvenile (J), males (M) and females(F) were recorded (Table-2) and divided into various
size groups (Table-3).

Specimens measuring a maxi-

mum of 16.0 mm were not sexed and were considered
as juveniles.

The lowest SVL (8.0 mm) of juveniles

from April through September is attributed to meta-morphosis time of the species during these months,
because the metamorphosing froglets were found to
be with a SVL of about 8.0 mm.

Based on SVL, thejuveniles were divided into two size groups (8.0-11.0and 12.0-16.0 mm). Both the size groups weremm

found from May to October and the former was also

Asiatic Herpetological ResearchVol. 7, p.

available during April.

Thisisindicative of early

breeding of the species, because metamorphosed fro-From November

glets were found during this month.

January, the larger size group juveniles werefound and this indicated growth in size.
until

A total of 388 males were collected over a periodof 12 months (Table 1) and the SVL ranged from 17.036.0 mm. All the males were grouped into three sizeand 31.0-36.0
groups (17.0-22.0 mm: 23.0-30.0mm) and the first two size groups were available dur-mm

ing all the months (except three specimens of the thirdgroup which were collected during May). The above
data indicated that both the juvenile, maturing andductedin

1997

orcaptivity

innaturalpopulations,byanalyzing marked individuals.
In general, growth rates of anurans have been
determined in three ways, depending on measurementof 1. preserved materials. 2. captive individuals and 3.
individuals either marked or samples taken from thesame natural population at different times during thesame growing season (Turner. 1960). The present

analysis of growth pattern ofL. limnocharis fits to the

because specimens of L. limnochariswere collected from their natural population over athird category,

period of 12 months.

Further, the sampling

methodmature males of various sizes were found in nature.

adopted was random. A total of 962 specimens (307juveniles, 388 males and 267 females) were sampled

The data on female population is comparable withmales, except the lower number (267) of the former,

collected during thewhich

could obviously be due to metamorphic event of theisLike males, thetypical for the species.

and the data indicated maximum number of juveniles

month of June (Table 1).

This

Dash and Mahanta 1993). whilefemales were also grouped into three similar size

species during June.

groups and all the size groups were available through-studying the community structure of ten anurans innatural populations, reported that L. limnocharis is theout the year. However, the number of two smaller sizegroupswerefemales.

The above population trend and size range islessthanthelargest

size

group of(dominant anuran in paddy fields.

Hence, the avail-ability of more juveniles than males and females dur-May-September

could

becomparedwithalso indicative of continuous growth of the species ining

natural environment.

population dynamics data of the species reported byDash and Mahanta (1993).

Discussion
Severalpreviousstudies

Acknowledgments(refertointroduction)

reported the growth pattern of temperate climate species of anurans and some of these studies (Wright,1914; Breckenridge and Tester, 1961; Bellis,1961;

Hedeen, 1972: Lillywhite et al.. 1973; Clarke, 1974)
Turner's (1960)
provide data on specific species.

We would like to express our sincere gratitude to Mr.
N. K. Acharya for statistical analysis of data and preparation of illustrations.

Financial assistance from theCSIR, New Delhi (Grant No. 37 (0843)/94/EMR-II
to S. K. D. is gratefully acknowledged.

review of available data on anuran growth pattern suggested that most of the studies have either been con-Appendix

ITables 1-3
Table 1. Cumulative data on population size of specimens of L. limnocharis collected for 12 months.

Year/Month)1997

Asiatic Herpetological ResearchVol. 7, p. 89

Vol. 7, p. 90

1997

Sahoo, G.

1991.

Bufo melanostictus.

Growth in natural population ofM. Phil, dissertation. Utkal Uni-Ting. Han-Po. 1951.

Duration of the tadpole stage ofthe green frog. Rana clamitans.

anurans.

Van Gelder, J. J. And H. C. J. Oomen. 1970. Ecological observations on Amphibia in the Netherlands. I.

Rana arvalis Nilsson: Reproduction, growth, migra-versity.

Turner.

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B.

1960.

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New York.

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