Zoological Studies

Vol. 51 No. 7, 2012

Studies on the Elemental Profile of Otoliths and Truss Network Analysis for Stock Discrimination of the Threatened Stinging Catfish Heteropneustes fossilis (Bloch 1794) from the Ganga River and Its Tributaries

Mohammad Afzal Khan1,*, Kaish Miyan1, Shahista Khan1, Devendra Kumar Patel2, and Nasreen Ghazi Ansari2

1Section of Fishery Science and Aquaculture, Department of Zoology, Aligarh Muslim University, Aligarh -202 002, India
2Indian Institute of Toxicology Research,Council of Scientific and Industrial Research, Lucknow-226 001, India

Mohammad Afzal Khan, Kaish Miyan, Shahista Khan, Devendra Kumar Patel and Nasreen Ghazi Ansari (2012) The present study was undertaken to identify different stocks of the stinging catfish Heteropneustes fossilis inhabiting the Ganga, Yamuna and Gomti Rivers of India using the elemental profile of sagittal otoliths and truss network analysis of the entire body shape.  Inductively coupled plasma-atomic emission spectrometry was used to estimate concentrations of 12 trace elements in otoliths, and 11 morphometric landmarks were chosen to construct a truss network of the fish in order to discriminate among stocks.  A discriminant function (DF) analysis of elemental profiles showed that Ba, Pb, Zn, and Sr successfully discriminated H. fossilis populations from different rivers.  DF-I, DF-II, and DF-III accounted for 76.1%, 17.9%, and 6%, respectively, of the among-group variability in the elemental profile of otoliths.  In the analysis of truss landmarks, the principal components, PC-I and PC-II, respectively accounted for 39.1% and 13.4%, while DF-I and DF-II, respectively accounted for 59.7% and 25.5% of the among-group variability.  The overall allocation success of individuals to their group of origin was high (98.7%) in the elemental profile of otoliths compared to truss measurements (72.3%).  The truss network analysis distinguished separate stocks of fish in the 3 rivers; however, the elemental profile of otoliths further discriminated the stocks at the 2 sampling stations within the Ganga River.

Key words: Stock structure, Heteropneustes fossilis, Truss morphometry, Otolith chemistry, Indian rivers.

*Correspondence: Tel: 91-9457007109.  E-mail:khanmafzal@yahoo.com