—Shortnose sturgeon Acipenser brevirostrum, a U.S. endangered species, has experienced a fourfold increase in abundance in the Hudson River in the past three decades. The age structure and trends in year-class strength of yearlings were investigated to evaluate the underlying pattern of annual recruitment that accompanied population recovery. Annuli in pectoral spine sections were used to estim...

Fish are the most numerous group of vertebrates in the world and their anatomy is still not completely studied. This article is aimed to present the morphological study of swimbladder in different species of ray-finned fish which have industrial value namely Russian sturgeon, American paddlefish (order Acipenseriformes), rainbow trout (order Salmoniformes), northern pike (order Esociformes), za...

Abstract Sturgeon and paddlefishes (Acipenseriformes) are cultured worldwide for commercial conservation purposes. Over the past decade, we have learned many sturgeon culture programs experience spontaneous autopolyploidy, or generation of triploidy without management intervention. Spontaneous autopolyploidy has been shown to negatively impact physiology, reproductive development fertility stur...

The micropyle number in the ova of sturgeon species from the South Caspian Sea was investigated. The study was conducted on female broodfishes of three species of sturgeon (Persian sturgeon Acipenser persicus, Stetates sturgeon A. stellatus and great sturgeon Huso huso) included 44 Persian sturgeon, 13 stellate sturgeon and 8 great sturgeon specimens. Fifty eggs were randomly collected from eac...

labeling system for all exports. While CITES deliberates, Russian reports suggest that the Caspian nations will lobby for an increased quota, following their meeting in Moscow earlier this month. The Caspian nations’ reprieve comes as the community awaits word of a decision by the U.S. Fish and Wildlife Service to list beluga as endangered. Such a ruling, now 2 months overdue, would ban all imp...

The Caspian seal (Pusa caspica) has declined by more than 90% since 1900 and is listed as endangered by IUCN. We made the first quantitative assessment of Caspian seal by-catch mortality in fisheries in the north Caspian Sea by conducting semi-structured interviews in fishing communities along the coasts of Russia (Kalmykia, Dagestan), Kazakhstan and Turkmenistan. We recorded a documented minim...