Genetic structure of populations and conservation issues relating to an endangered catfish, Clarias batrachus, in India.

The Asian catfish, Clarias batrachus (Linnaeus, 1758), is a highly valued species endemic to India that is currently in drastic decline in most of its natural habitat. The present study was undertaken to document the genetic structure of populations of this species using mitochondrial DNA markers, specifically from the cytochrome B and D-loop regions. Specimens from eight wild populations were collected and analyzed from different regions in India. The genetic variation within and among populations was evaluated using a range of descriptive statistics. The analysis described here provides a broad and consistent view of population structure and demographic history of populations of C. batrachus. Although there was some genetic structuring consistent with regional differences, all eight populations examined here showed relatively low levels of genetic variation in terms of both haplotype and nucleotide diversities in the different analyses used. However, a number of private haplotypes were discovered, and this may provide valuable information for future selective breeding program and conservation management. The results may aid in the design and implementation of strategies for the future management of this endangered catfish C. batrachus in India.