Molecular analysis in the conservation of sturgeons and paddlefish

Abstract

Sturgeon and paddlefish populations worldwide have declined because of anthropogenic influences. The structure and magnitude of genetic diversity of natural populations serves to buffer these fishes against environmental variation and should be maintained. Modern molecular biological techniques provide the ability to sensitively characterize and quantify the extent of genetic variation in natural populations.We provide a summary of those problems in sturgeon population biology that are amenable to investigation with DNA approaches, and their applications to date. These have included genetic identification and discrimination of taxa. identification of hybrids, stockidentification, mixed-stock analysis,and estimation of gene flow and homing fidelity. To date, almost all studies have been restricted to North American fauna. Improvements to these technologies, including nondestructive sampling, should permit more widespread application of molecular approaches to problems of acipenseriform conservation. We suggest that the use of more sensitive molecular tools such as analyses of hypervariable repetitive and non-coding single copy nuclear DNA may assist management even in those taxa which exhibit overall low levels of genetic diversity.