Stock structure analysis of oil sardine Sardinella longiceps from southeast and southwest coasts of India - Original Article

Sep 5, 2026

A total of 200 oil sardine (Sardinella longiceps) specimens were collected from Kochi (southwest coast) and Chennai (southeast coast) and analyzed using truss network analysis. A truss network was built by interconnecting 10 landmarks to generate 21 truss distance variables, followed by factor analysis. Results showed no separation between stocks of the two coasts. Marginal differences in shape and form were linked to ecological habitat variation, reflected in length-weight relationships and feeding intensity differences.

LanguageEnglish

CategoryGeneral

FormatPDF

Pages7

Reading Time3 min

AccessFree to download

Abstract

Introduction

Material and methods

Sample collection

Truss morphometrics

Results and discussion

Conclusion

Available online [at: www.mbai.org.in](at: www.mbai.org.in) doi: 10 . 6024/jmbai.2015.57.1.01820-02 Stock structure analysis of oil sardine Sardinella longiceps (Valenciennes, 1847) from southeast and southwest coasts of India R. Remya*, E. Vivekanandan1, G. B. Sreekanth2, T. V. Ambrose, Preetha G. Nair, U. Manjusha, S. Thomas and K. S. Mohamed Central Marine Fisheries Research Institute, P. B. No. 1603, Kochi-682018, Kerala, India. 1Madras Research Centre of Central Marine Fisheries Research Institute, 75, Santhome High Road, Chennai-600028, Tamil Nadu, India. 2ICAR Research Complex for Goa, Old Goa, Goa. *Correspondence e-mail: [remyarraj@gmail.com](remyarraj@gmail.com) Received:04 Sep 2014, Accepted: 06 Feb 2015, Published: 15 Mar 2015 Original Article Abstract A total of 200 specimens of oil sardine Sardinella longiceps collected from Kochi in the southwest coast and Chennai in the southeast coast were subjected to truss analysis. A truss network was constructed by interconnecting 10 landmarks to form a total of 21 truss distance variables extracted from the landmarks. The transformed truss measurements were subjected to factor analysis which revealed that there is no separation of the stocks along southeast and southwest coasts. The marginal differences in shape and form are attributed to the ecological differences in the habitats which are evident from differences in length weight relationships and feeding intensity of the population along these two coasts. Keywords: truss network analysis, stock structure, phenotypic homogeneity Introduction The oil sardine, Sardinella longiceps forms one of the major single species fisheries contributing about 0.72 million tons along the Indian coasts (CMFRI, 2013) . Knowledge on the stock structure of the target species is fundamental to formulate resource management plans and for sustaining the marine fish stocks (Shaklee and Bentzen, 1998) . During the last 10 years, oil sardine abundance has increased along the southeast coast which is stated to be an impact of changing climatic conditions (Vivekanandan, 2011) . It is not clear whether the oil sardine populations of the southwest and southeast coasts are from a single stock. Therefore there is a need to assess the stock structure of the species along the southeast and southwest coasts of India. Truss network analysis (Strauss and Bookstein, 1982) is a quantitative method for describing the shape of fish (Cavalcanti et al., 1999; Sen et al., 2011) by measuring the morphometric variations between species and also between stocks of a species (Turan, 1999) . This system is more effective in identifying stocks and differentiating species in comparison with the traditional morphometric methods. For example Sajina et al. (2011) were able to show that the horse mackerel, Mega laspis cordyla from four areas, two each from the east (Digha and Mandapam regions in the Bay of Bengal) and west (Cochin and Mumbai regions of the Arabian sea) coasts of the Indian peninsula belonged to separate spawning stock populations. Similarly, Sen et al. (2011) studied the stock structure of Decapterus russelli from east and west coasts of J. Mar. Biol. Ass. India, 57 (1), January-June 2015 Stock structure analysis of oil sardine from southern coasts of India. India which revealed the existence of two morphologically different stocks. Jayasankar et al. (2004) who carried out morphometric and genetic analysis of the Indian mackerel (Rastrelliger kanagurta) could not find significant differences among the three populations from selected centres in the east and west coasts of India. Mohandas (1997) analysed the morphometric data of oil sardine populations collected from Cochin, Calicut, Mangalore and Mandapam regions and observed that the populations from Calicut and Mandapam appeared to be morphologically similar. The oil sardine populations along Kochi and Chennai coasts show apparent visual differences in shape and form. T

FAQs

How were the oil sardine samples collected for the study?

Two hundred adult Sardinella longiceps specimens were collected from Chennai (southeast coast) and Kochi (southwest coast) during February to November 2011 using ringseines and gillnets.

What method was used to analyze stock structure?

Truss network analysis was applied. Ten homologous anatomical landmarks were used to construct a network and extract 21 truss distance variables, which were then analyzed using factor analysis.

Did the study find separate stocks between the two coasts?

No. Factor analysis revealed no separation of stocks between the southeast and southwest coasts, while marginal shape differences were attributed to ecological differences in the habitats.

Sep 5, 2026

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