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Puntius chelynoides (McClelland, 1839) from Garhwal Himalaya, India. By J. I. Mir1 .... along the Pacific coast of the Baja California Peninsula, Mexico. J. Appl.

Journal of

Applied Ichthyology J. Appl. Ichthyol. (2013), 1–2 © 2013 Blackwell Verlag GmbH ISSN 0175–8659

Received: September 25, 2012 Accepted: April 15, 2013 doi: 10.1111/jai.12252

Technical contribution Length–weight and length–length relationships of the vulnerable dark mahseer Puntius chelynoides (McClelland, 1839) from Garhwal Himalaya, India By J. I. Mir1, O. Gusain2, M. P. Gusain2, F. A. Mir3, U. K. Sarkar1 and A. Pandey1 1

National Bureau of Fish Genetic Resources, Lucknow, India; 2Department of Zoology and Biotechnology, Hemwati Nandan Bahuguna Garhwal University, Srinagar Garhwal, India; 3P. G. Department of Zoology, University of Kashmir, Srinagar, India

The present study describes the length–weight (LWR) and length–length relationships (LLR) of Puntius chelynoides (McClelland, 1839), commonly known as the dark mahseer, a coldwater fish species which inhabits fast-flowing hillstreams of India and Nepal. A total of 422 specimens were collected between January and June 2010 from a spring-fed stream in Garhwal Himalaya, India. No information regarding LWRs, LLRs or K of this species was available in FishBase.

2010. Total length (TL) and fork length (FL) to the nearest 0.1 cm and body weight (BW) to the nearest 0.1 g were recorded for each individual. Identification of fishes was done following Day (1878) and Talwar and Jhingran (1991). Monthly LWRs were determined by the linear regression equation: log W = log a + b log TL, where W is the weight of the fish (g), TL is the total length (cm), a is the intercept and b the slope of the regression curve (Ruiz-Campos et al., 2010). Length–length relationships, i.e. TL–FL were calculated by linear regression (Hossain, 2010).

Introduction

Results and discussion

The dark mahseer, Puntius chelynoides, is a commercially important freshwater fish of India, native to coldwater streams of Garhwal Himalaya. The male attains a maximum total length of 66 cm (Menon, 1999). This species is listed as vulnerable (VU) in the IUCN critically endangered category in IUCN (2012). Menon (1999) noted that this species was earlier known from Assam. Menon (2004) suggests that this species is probably extinct in Assam and thus is now confined to the headwaters of the Ganges. According to Ranjan et al. (2007), P. chelynoides is found only in upstream but not in downstream regions.

Length–weight relationship statistics for P. chelynoides are presented in Table 1. The linear regressions were highly significant (P < 0.001), with the coefficient of determination (r2) values being >0.97. The length–length relationship was described by the equation, Log TL = 2.086 Log FL 1.170 (n = 422; r2 = 0.965). FishBase had no LWRs or LLR records for P. chelynoides as of March 2013 (Froese and Pauly, 2011). The values of b for this species however, were within the normal range of 2.5–3.5, as suggested by Froese (2006). In conclusion this study has provided first basic information on the LWR and LLR of P. chelynoides that would be useful for fishery biologists/managers.

Summary

Materials and methods Measurement of length and weight of 422 specimens of P. chelynoides from Bachchan Gad (30°15′N; 78°55′E), a spring-fed stream on the Alaknanda River (tributary of Ganges basin) India, were collected from January to June

Acknowledgements We wish to acknowledge the fishermen for their cooperation in collecting specimens. We would also like to express our

Table 1 Monthly descriptive statistics and estimated length–weight relationship parameters of Puntius chelynoides in a spring-fed stream, Garhwal Himalaya (India), January to June 2010 Total length (cm)

Total body weight (g)

Regression parameters

Months

N

Minimum

Maximum

Minimum

Maximum

a*

b  SE

January February March April May June

77 72 67 73 68 65

10.0 9.5 7.5 6.5 6.0 5.8

37.5 38.5 32.5 41.0 38.5 36.8

18.5 15.7 15.3 12.2 13.8 10.8

800.6 910.4 730.5 950.6 810.5 670.3

0.0046 0.0118 0.0166 0.0155 0.0111 0.0056

2.75 2.86 2.89 2.94 2.88 2.60

     

0.03 0.01 0.01 0.04 0.01 0.02

95% Cl of a

95% Cl of b

r2

0.0042–0.0049 0.0089–0.0136 0.0098–0.0173 0.0138–0.0175 0.0100–0.0115 0.0038–0.0069

2.69–2.86 2.84–2.86 2.86–2.91 2.92–2.96 2.84–2.92 2.56–2.68

0.99 0.98 0.99 0.99 0.98 0.98

N, total number of samples; a, intercept; b, slope; CL, Confidence limits; r2, Coefficient of determination. *Anti-log a.

2

gratitude to Dr. Froese and Prof. Rosenthal (Editor-in-Chief, J. Appl. Ichthyology.) for bringing forth such informative publications, especially that of Dr. Froese (2006). And lastly, thanks are also due to former HOD (Prof. J. P. Bhatt), Department of Zoology and Biotechnology, HNB Garhwal University Srinagar Garhwal, for providing the necessary facilities to carry out this work. References Day, F., 1878: The fishes of India; being a natural history of the fishes known to inhabit the seas and fresh waters of India, Burma and Ceylon, Vol. 1. Bernard Qualitch, London, pp. 529–533. Froese, R., 2006: Cube law, condition factor and weight length relationship: history, meta-analysis and recommendations. J. Appl. Ichthyol. 22, 241–253. Froese, R.; Pauly, D. (Eds), 2011: FishBase. World Wide Web electronic publication. Available at: http://www.fishbase.org,Version 3 (accessed on 20 March 2012). Hossain, M. Y., 2010: Length-weight, length-length relationships and condition factors of three schibid catfishes from the Padma River, northwestern Bangladesh. Asian Fish. Sci. 23, 329–339.

J. I. Mir et al. IUCN, 2012: IUCN Red List of Threatened Species. Version 2012.1 Downloaded in June 2012. Menon, A. G. K., 1999: Checklist – Freshwater Fishes of India. Rec. Zool. Surv. India, Misc. Publ., Occas. Pap. No. 175, pp. 366. Menon, A. G. K., 2004: Threatened fishes of India and their conservation. Zoological Survey of India, Kolkata, India. Ranjan, J. B.; Herwig, W.; Subodh, S.; Michael, S., 2007: Fish base study of the impacts of dams in different rivers of Nepal and its seasonal variations. Int. J. Phys. Sci. 19, 27–44. Ruiz-Campos, G.; Ramirez-Valdez, A.; Gonzalez-Guzman, S.; Gonzalez-Acosta, A. F.; Acosta Zamorano, D., 2010: Length-weight and length-length relationships for nine rocky tidal pool fishes along the Pacific coast of the Baja California Peninsula, Mexico. J. Appl. Ichthyol. 26, 118–119. Talwar, P. K.; Jhingran, A. G., 1991: Inland fishes of India and adjacent countries. Oxford and IBH Publishing Co, New Delhi. Author’s address: Omprakash Gusain, Departement of Zoology and Biotechnology, Hemwati Nandan Bahuguna Garhwal University, Srinagar Garhwal-246174, Uttarkhand, India. E-mails: [email protected]; [email protected]