Sturgeon and paddlefish: Review of research on broodstock and early life stage management

Sturgeon aquaculture has taken a parallel yet unique path relative to other teleost rearing. One of the driving factors has been the fact that virtually all extant species are facing extinction; thus, laws concerning the transport and processing of sturgeon are stringent. As a result, most sturgeon companies vertically integrate the farming process from hatchery to harvest, in contrast to the production of other commercial fish species (e.g., trout, sea bass, salmon), where farmers tend to purchase fry from producers specialized only in the production of that life stage and sell product to unaffiliated fish processors. Sturgeon aquaculture is furthermore unique in the extremely high value of the main product (caviar). The secondary product (meat) also surpasses other finfish aquaculture products' average price per weight. These expensive outputs reveal the greatest challenge in production — an exceptionally long time to market from larvae to harvestable adults. For all their rigor and robustness as juveniles and adults, sturgeon species are highly fragile during larval stages. Due to the unique legal framework around sturgeon cultivation, aquaculturists often specialize in regional species, although some hybrids have achieved global popularity. This lends to a heterogenous swath of literature on best cultivation and management practices, especially at early growth stages. Nonetheless, the role of aquaculture as both a food source and restocking program to thwart further extinction of sturgeon species has hardly been fully tapped. In light of the many challenges, this review examines recent advances in sturgeon farming with an emphasis on broodstock and early life-stage management to summarize studies that can help researchers and farmers assess the industry's current state.