ABSTRACT
The present study attempts to develop a comprehensive Length-Weight relationship and
relative condition Factor (Kn) of Barilius sacra collected from River Torsa in West Bengal. The value
of exponent ‘n’ in the equation W = cLn was found to be 2.47 for the species Barilius sacra. The
computed ‘t’ value indicated that the ‘n’ value of the species is not significantly different from the
expected value ‘3‘ and hence the Cube Law W = cLn
hold good in the case of Barilius sacra. The
computed co-relation co-efficient (r) in Barilius sacra was 0.961 which is very closer to 1 indicating
that there is high positive correlation between length and weight in the species. The relative
Condition Factor (Kn) remained greater (1.16) than 1 for the species indicating their general well
being to be good in Torsa river in West Bengal.
KEYWORDS
Length-weight relationship,Relative condition factor,Barilius sacra,Torsa River,
West Bengal.
INTRODUCTION
According to Le Cren, knowledge of the length-weight relationship of a fish is essential,
since various important biological aspects, viz., general well being of fish, appearance of first
maturity, onset of spawning etc., can be assessed with the help of condition factor, a derivative of
this relationship, moreover, the length-weight relationship (LWR) of fish is an important fishery
management tool because they allow the estimation of the average weight of the fish of a given
length group by establishing a mathematical relationship between the two. As length and weight of
fish are among the morphometric characters, they can be used for the purpose of taxonomy and
ultimately in fish stock assessment1
. In fisheries Science, the condition factor is used in order to
compare the ‘condition’, ‘fatness’ or well being of fish and it is based on the hypothesis that heavier
fish of a given length are in better condition. Condition factor has also been used as an index of
growth and feeding intensity. An extensive research on length-weight relationship of commercial
freshwater fishes from different water bodies in India is already reported Das et. al 2, Das et al. 6.
.
This study reports the LWR of Barilius sacra of Torsa River in West Bengal, India.
MATERIALS AND METHODS
In fishes, generally the growth pattern follows the cube law. Such relationship for the fishes
will be vaild when the fish grows isometrically. In such cases, the experimental value must be
exactly 3. But, in reality, the actual relationship between length and weight may depart from the ideal
value due to environmental conditions or condition of fish. This relationship is expressed by the
equation W= aLn
. This equation was used by several workers for different fish species form different
habitats.
In this study, a total 15 fish specimens comprises of Barilius sacra ranged from 53-97 mm in
length and 1.82-7.23 gm in weight were studied for the length weight relationship. The species were
identified by using the key provided by Jayaram7
. Individual measurements of fish species pertaining
to total length (TL cm) and total weight (g) were done with the help of precision Vernier Calliper and
Digital Sartorious Electronic Balance respectively. The total length (TL) of each fish species were
taken from the tip of snout to longest ray of caudal fin. Fish weight was measured after blot drying.
The LWR was established by fitting equation of the form
W=cLn …………………….(1)
Where W is the weight of the fish, ‘L’ its length and ‘c’ and ‘n’ are constants. The equation 1
could be expressed in the linear form by using logarithms, as given below:
Log W = Log c + n Log L
The estimates of the constants c and n were obtained empirically by using the formulae, as
given below:
Significance of the variation in estimates of n from the expected value 3 (cube law). Weights
were estimated for different lengths using relationship equation. The relation between length and
weight for each fish was computed with help of statistics. The Fulton’s Condition Factor (K) was
computed by using the formulae, as given below:
RESULTS AND DISCUSSION
The formula correlating L-W of Barilius sacra is given bellow:
Log W = -4.069 + 2.47 Log L
It is evident from the result that the ‘n’ value of length-weight relationship was found 2.47,
represents fish that becomes less routed as length increases, indicating the allometric pattern of
growth in the fish.
The computed correlation co-efficient (r) value in Barilius sacra was found to be 0.961 which
indicates, there is high positive correlation between the length and weight in the species Das et al 6
.
The Condition factor (Kn) is an indication of general well being of fishes. The Le Cren’s
condition factor (Kn) of Barilius sacra was found to be 1.16 which is greater than 1, Thus, indicating
their general well being to be good. Therefore all these observations appear to indicate that single
value of ‘c’ and ‘n’ may not be responsible for the entire size range of the fish.
The observed average weight of the species against the observed length with a predicted data,
a parabolic curve has been obtained and a logarithmic graph prepared with the observed data of log L
and log W with a predicted data showed a straight line relationship. The exponential value for
Barilius sacra is the hypothetical value (3), ‘n’ value was 2.47 and the correlation co-efficient was
0.961. In length-weight relationship of Barilius sacra, weight increases with length. Thus, it is clear
that these fishes maintain its shape throughout its life.
REFERNCES
1. Das BK, and Kar D. Habitat Mapping, Spatial Analysis to Fish Diversity of River Subansiri
during Winter Season in Assam and Arunachal Pradesh (India). Environment and Ecology.
2011; 29 (4A): 1948-1951.
2. Das BK, Dutta B, Singh NgR and Kar D. Length-Weight Relationship of Labeo calbasu
(Hamilton-Buchanan) from Sone Beel the Biggest Wetland of Assam, India. PARIPEX-In.
Journal of Research. 2013; 2 (10): 11-13.
3. Das BK, Chakraborty A, and Kar D. Calculation of Length of a Fish Using Two-Dimensional
Geometry. International Journal of Scientific Research. 2013; 2 (10): 48-51.
4. Das BK, Boruah P, and Kar D. Study of Seasonal Variation of Water Quality of River Siang in
Arunachal Pradesh, India. IOSR Journal of Environmental Science. Toxicology and Food
Technology (IOSR-JESTFT). 2014; 8 (2IV): 11-20.
5. Das BK, Singh NgR, Dutta B and Kar D. Length Weight Relationship of Labeo rohita
(Hamilton-Buchanan) and Labeo gonius (Hamilton-Buchanan) in Sone Beel the biggest
Wetland of Assam, India. Journal of environmental Research and Development. 2014; 8 (3A):
587-593.
6. Jayaram KC. The freshwater fishes of the Indian region. Narendra Publishing House, Delhi,
India. 1999; pp. 551.
7. Kar D. Fundamentals of Limnology and Aquaculture Biotechnology. Daya Publishing House,
New Delhi, India. 2007; pp. xiv + 609.
8. Kar D. Wetlands and Lakes of the World. Springer (London). 2013; pp. xxx + 687.
9. Choudhury S and Dutta K. Interrelationship of Five Species of the Genus Labeo by
Morphometric Analysis. IOSR Journal of Pharmacy and Biological Sciences. 2012; 2 (6): 35-
39.
10. Kar D and Barbhuiya MH. Length-Weight Relationship and relative condition factor in Hilsa
(Tenulosa) ilisha (Hamilton) of Barak Drainge in Assam. Indian J. of Environ and Ecoplan.
2005; (05): 265-267.
11. Ahmed EO, Ali ME and Aziz AA. Length-Weight Relationships and Condition factors of six
fish species in Atbara River and Khashm el- Girba Reservoir, Sudan. International Journal of
Agriculture Sciences. 2011; 3 (1): 65-70.
12. Simon KD and Mazlan AG. Length-Weight and Length-Length Relationships of Archer and
Puffer Fish Species. The Open Fish Science Journal. 2008; (1): 19-22.
13. Oribhabor BJ, Ogbeibu AE and Udo MT. The Length-Weight Relationships of Brackish
Water/Marine Fish Species Assemblage in a Niger Delta Mangrove Creek, Nigeria. Current
Research Journal of Biological Sciences. 2011; 3 (6): 616-621.
14. Isa MM, Abdul Basri MN, Zawawi MZM, Yahyal K and Nor Md SA. Length-weight
Relationships of Some Important Estuarine Fish Species from Merbok Estuary. Kedah. Journal
of Natural Sciences Research. 2012; 2 (2): 8.
15. LeCren. The Length-Weight relationship and Seasonal cycle in Gonad Weight and condition in
Perch. Journal of Animal Ecology. 1951; (20): 201-209.
16. Orhan AK, Kutlu S and Aydin I. Length Weight Realtionship for 16 Species from the eastern
Black Sea, Tirkiye. Turkish Journal of Fisheries and aquaculture Sciences. 2009; (9): 125-125.
17. Sangun L, Akama E and Akar M. Weight-Length Relationships for 39 Fish Species from the
North-Eastern Mediterranean Coast of Turkey. Turkish Journal of Fisheries and Aquatic
Sciences. 2007; (7): 37-40.
18. Shadi A, Mediseh SD, Kouchanian P and Gandomi Y. Length-Weight Relationships for 6 Fish
Species from Khuzestan (North of Persian Gulf), Iran. World Journal of Fish and Marine
Sciences. 2011; 3 (2): 129-131.
The present study attempts to develop a comprehensive Length-Weight relationship and
relative condition Factor (Kn) of Barilius sacra collected from River Torsa in West Bengal. The value
of exponent ‘n’ in the equation W = cLn was found to be 2.47 for the species Barilius sacra. The
computed ‘t’ value indicated that the ‘n’ value of the species is not significantly different from the
expected value ‘3‘ and hence the Cube Law W = cLn
hold good in the case of Barilius sacra. The
computed co-relation co-efficient (r) in Barilius sacra was 0.961 which is very closer to 1 indicating
that there is high positive correlation between length and weight in the species. The relative
Condition Factor (Kn) remained greater (1.16) than 1 for the species indicating their general well
being to be good in Torsa river in West Bengal.
KEYWORDS
Length-weight relationship,Relative condition factor,Barilius sacra,Torsa River,
West Bengal.
INTRODUCTION
According to Le Cren, knowledge of the length-weight relationship of a fish is essential,
since various important biological aspects, viz., general well being of fish, appearance of first
maturity, onset of spawning etc., can be assessed with the help of condition factor, a derivative of
this relationship, moreover, the length-weight relationship (LWR) of fish is an important fishery
management tool because they allow the estimation of the average weight of the fish of a given
length group by establishing a mathematical relationship between the two. As length and weight of
fish are among the morphometric characters, they can be used for the purpose of taxonomy and
ultimately in fish stock assessment1
. In fisheries Science, the condition factor is used in order to
compare the ‘condition’, ‘fatness’ or well being of fish and it is based on the hypothesis that heavier
fish of a given length are in better condition. Condition factor has also been used as an index of
growth and feeding intensity. An extensive research on length-weight relationship of commercial
freshwater fishes from different water bodies in India is already reported Das et. al 2, Das et al. 6.
.
This study reports the LWR of Barilius sacra of Torsa River in West Bengal, India.
MATERIALS AND METHODS
In fishes, generally the growth pattern follows the cube law. Such relationship for the fishes
will be vaild when the fish grows isometrically. In such cases, the experimental value must be
exactly 3. But, in reality, the actual relationship between length and weight may depart from the ideal
value due to environmental conditions or condition of fish. This relationship is expressed by the
equation W= aLn
. This equation was used by several workers for different fish species form different
habitats.
In this study, a total 15 fish specimens comprises of Barilius sacra ranged from 53-97 mm in
length and 1.82-7.23 gm in weight were studied for the length weight relationship. The species were
identified by using the key provided by Jayaram7
. Individual measurements of fish species pertaining
to total length (TL cm) and total weight (g) were done with the help of precision Vernier Calliper and
Digital Sartorious Electronic Balance respectively. The total length (TL) of each fish species were
taken from the tip of snout to longest ray of caudal fin. Fish weight was measured after blot drying.
The LWR was established by fitting equation of the form
W=cLn …………………….(1)
Where W is the weight of the fish, ‘L’ its length and ‘c’ and ‘n’ are constants. The equation 1
could be expressed in the linear form by using logarithms, as given below:
Log W = Log c + n Log L
The estimates of the constants c and n were obtained empirically by using the formulae, as
given below:
Significance of the variation in estimates of n from the expected value 3 (cube law). Weights
were estimated for different lengths using relationship equation. The relation between length and
weight for each fish was computed with help of statistics. The Fulton’s Condition Factor (K) was
computed by using the formulae, as given below:
RESULTS AND DISCUSSION
The formula correlating L-W of Barilius sacra is given bellow:
Log W = -4.069 + 2.47 Log L
It is evident from the result that the ‘n’ value of length-weight relationship was found 2.47,
represents fish that becomes less routed as length increases, indicating the allometric pattern of
growth in the fish.
The computed correlation co-efficient (r) value in Barilius sacra was found to be 0.961 which
indicates, there is high positive correlation between the length and weight in the species Das et al 6
.
The Condition factor (Kn) is an indication of general well being of fishes. The Le Cren’s
condition factor (Kn) of Barilius sacra was found to be 1.16 which is greater than 1, Thus, indicating
their general well being to be good. Therefore all these observations appear to indicate that single
value of ‘c’ and ‘n’ may not be responsible for the entire size range of the fish.
The observed average weight of the species against the observed length with a predicted data,
a parabolic curve has been obtained and a logarithmic graph prepared with the observed data of log L
and log W with a predicted data showed a straight line relationship. The exponential value for
Barilius sacra is the hypothetical value (3), ‘n’ value was 2.47 and the correlation co-efficient was
0.961. In length-weight relationship of Barilius sacra, weight increases with length. Thus, it is clear
that these fishes maintain its shape throughout its life.
REFERNCES
1. Das BK, and Kar D. Habitat Mapping, Spatial Analysis to Fish Diversity of River Subansiri
during Winter Season in Assam and Arunachal Pradesh (India). Environment and Ecology.
2011; 29 (4A): 1948-1951.
2. Das BK, Dutta B, Singh NgR and Kar D. Length-Weight Relationship of Labeo calbasu
(Hamilton-Buchanan) from Sone Beel the Biggest Wetland of Assam, India. PARIPEX-In.
Journal of Research. 2013; 2 (10): 11-13.
3. Das BK, Chakraborty A, and Kar D. Calculation of Length of a Fish Using Two-Dimensional
Geometry. International Journal of Scientific Research. 2013; 2 (10): 48-51.
4. Das BK, Boruah P, and Kar D. Study of Seasonal Variation of Water Quality of River Siang in
Arunachal Pradesh, India. IOSR Journal of Environmental Science. Toxicology and Food
Technology (IOSR-JESTFT). 2014; 8 (2IV): 11-20.
5. Das BK, Singh NgR, Dutta B and Kar D. Length Weight Relationship of Labeo rohita
(Hamilton-Buchanan) and Labeo gonius (Hamilton-Buchanan) in Sone Beel the biggest
Wetland of Assam, India. Journal of environmental Research and Development. 2014; 8 (3A):
587-593.
6. Jayaram KC. The freshwater fishes of the Indian region. Narendra Publishing House, Delhi,
India. 1999; pp. 551.
7. Kar D. Fundamentals of Limnology and Aquaculture Biotechnology. Daya Publishing House,
New Delhi, India. 2007; pp. xiv + 609.
8. Kar D. Wetlands and Lakes of the World. Springer (London). 2013; pp. xxx + 687.
9. Choudhury S and Dutta K. Interrelationship of Five Species of the Genus Labeo by
Morphometric Analysis. IOSR Journal of Pharmacy and Biological Sciences. 2012; 2 (6): 35-
39.
10. Kar D and Barbhuiya MH. Length-Weight Relationship and relative condition factor in Hilsa
(Tenulosa) ilisha (Hamilton) of Barak Drainge in Assam. Indian J. of Environ and Ecoplan.
2005; (05): 265-267.
11. Ahmed EO, Ali ME and Aziz AA. Length-Weight Relationships and Condition factors of six
fish species in Atbara River and Khashm el- Girba Reservoir, Sudan. International Journal of
Agriculture Sciences. 2011; 3 (1): 65-70.
12. Simon KD and Mazlan AG. Length-Weight and Length-Length Relationships of Archer and
Puffer Fish Species. The Open Fish Science Journal. 2008; (1): 19-22.
13. Oribhabor BJ, Ogbeibu AE and Udo MT. The Length-Weight Relationships of Brackish
Water/Marine Fish Species Assemblage in a Niger Delta Mangrove Creek, Nigeria. Current
Research Journal of Biological Sciences. 2011; 3 (6): 616-621.
14. Isa MM, Abdul Basri MN, Zawawi MZM, Yahyal K and Nor Md SA. Length-weight
Relationships of Some Important Estuarine Fish Species from Merbok Estuary. Kedah. Journal
of Natural Sciences Research. 2012; 2 (2): 8.
15. LeCren. The Length-Weight relationship and Seasonal cycle in Gonad Weight and condition in
Perch. Journal of Animal Ecology. 1951; (20): 201-209.
16. Orhan AK, Kutlu S and Aydin I. Length Weight Realtionship for 16 Species from the eastern
Black Sea, Tirkiye. Turkish Journal of Fisheries and aquaculture Sciences. 2009; (9): 125-125.
17. Sangun L, Akama E and Akar M. Weight-Length Relationships for 39 Fish Species from the
North-Eastern Mediterranean Coast of Turkey. Turkish Journal of Fisheries and Aquatic
Sciences. 2007; (7): 37-40.
18. Shadi A, Mediseh SD, Kouchanian P and Gandomi Y. Length-Weight Relationships for 6 Fish
Species from Khuzestan (North of Persian Gulf), Iran. World Journal of Fish and Marine
Sciences. 2011; 3 (2): 129-131.
0 Comments