Ossetra dwells another type of sturgeon, Siberian sturgeon ("Acipenser Baerii"), which is farmed all over the world because it can adapt to a wider range of habitats. It begins to produce caviar faster than "Acipenser gueldenstaedtii". Throughout the entire history of black caviar consumption, reference to Ossetra was made only to the fish that was caught first in Imperial Russia, then the USSR, and now in the Russian Federation. Today, Caspian Ossetra is facing extinction in its native habitat. Farming sturgeon is the only way to continue the production of high-quality caviar. Continuous drastic declines in natural sturgeon populations over the
Types of membership of Opus Dei for the contributions that they may have made to Opus Dei during their time in the organisation, this applies to all categories of membership. When, however, someone leaves the prelature unlawfully (i.e. without the permission of the Prelate) he or she commits mortal sin. Nevertheless, the Congregation for Bishops states: "The laity incorporated in the Prelature Opus Dei continue to be faithful of the dioceses in which they have their domicile or quasidomicile and are, therefore, under the jurisdiction of the diocesan bishop in what the law lays down for all the ordinary faithful". Types of membership of Opus Dei