Biology, Conservation and Sustainable Development of Sturgeons

Abstract

Sturgeons can be considered living fossils having many morphologic and biological features of ancient fish; in fact, sturgeon fossils date from about 300 million years ago, and they have essentially maintained their present features for more than 200 million years. Thus, this phylogenetic group presents unique characteristics from a biological point of view, representing a real challenge for researchers. Furthermore, sturgeons are of the utmost interest also from an applied, economic perspective. In this regard, these species are in great demand, not only for the preparation of caviar, which reaches exceptionally high prices in the international markets, but also for the meat. There are about 27 sturgeon species living in the seas and rivers of the Northern hemisphere. However, sturgeons are virtually unknown from a scientific point of view and, most importantly, they might soon become a part of the story of evolution; over-fishing, and the loss of their natural habitats might soon make it impossibile to learn about them. In fact, the wild populations of the majority of sturgeon species are actually in great danger of extinction all over the world. Being a diadromous species, that is, migrating from the sea to rivers and lakes for spawning and also staying there during the early juvenile years, and maturing slowly to the reproduction age, make them particularly vulnerable to excessive capture for commercial purposes; just as important is the degradation of their natural habitats due to human establishment and industry. In this situation, it is important to develop strategies for their conservation in natural habitats and also for their culture in fish farms, not only for providing meat and caviar for the market, but also to raise adequate reproducer sturgeons, with the three main objectives of conservation, repopulation of their original habitats and aquaculture. Rational recovery of the wild sturgeon species requires a sound knowledge of their taxonomy, biogeographical distribution, and biological features. Furthermore, information concerning previous efforts for the conservation and recovery of this group in Europe, Asia and America is also needed...