Water projects designed to extract fresh water for local urban, industrial and agricultural use throughout rivers and estuaries worldwide have contributed to the fragmentation and degradation of suitable habitat for native fishes. The number of water diversions located throughout the Sacramento-San Joaquin watershed in California's Central Valley exceeds 3300, and the majority of these are unsc...

Sturgeons are among the most CO2 tolerant of fishes investigated to date. However, the basis of this exceptional CO2 tolerance is unknown. Here, white sturgeon, Acipenser transmontanus, were exposed to elevated CO2 to investigate the mechanisms associated with short-term hypercarbia tolerance. During exposure to 1.5 kPa Pco2, transient blood pH [extracellular pH (pHe)] depression was compensate...

While the current expansion of conservation genetics enables to address more efficiently the management of threatened species, alternative methods for genetic relatedness data analysis in polyploid species are necessary. Within this framework, we present a standardized and simple protocol specifically designed for polyploid species that can facilitate management of genetic diversity, as exempli...

In this essay, three lines of evidence are developed that sturgeons in the Chesapeake Bay and elsewhere are unusually sensitive to hypoxic conditions: 1. In comparison to other fishes, sturgeons have a limited behavioral and physiological capacity to respond to hypoxia. Basal metabolism, growth, feeding rate, and survival are sensitive to changes in oxygen level, which may indicate a relatively...

The range of Shovelnose Sturgeon (SVS) Scaphirhynchus pla-torynchus in the great rivers of central North America has contracted, but most remaining populations are considered stable, likely due to a combination of successful harvest regulations and longitudinal continuity of many river reaches, despite damming in upper reaches. The evolutionary relationships of SVS relative to sister taxa is st...

EFFECTS OF HYDRAULIC DREDGING AND VESSEL OPERATION ON ATLANTIC STURGEON BEHAVIOR IN A LARGE COASTAL RIVER Michael R. Barber, B.S. A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Biology at Virginia Commonwealth University. Virginia Commonwealth University, 2017. Major Advisor: Dr. Greg Garman, Director of Rice Rivers Center, Center for Enviro...

Primordial germ cells (PGCs) arise elsewhere in the embryo and migrate into developing gonadal ridges during embryonic development. In several model animals, formation and migration patterns of PGCs have been studied, and it is known that these patterns vary. Sturgeons (genus Acipenser) have great potential for comparative and evolutionary studies of development. Sturgeons belong to the super c...

The objective of this study was to compare biological parameters such as length, weight, age, caviar production indices, caviar/weight, growth, condition factor and sex ratios of Persian sturgeon (Acipenser persicus Borodin, 1897) and Russian sturgeon (A. gueldenstaedti Brandt & Ratzeburg, 1833) in the Caspian Sea during 1990-2014. The results showed that a variety of differences between this t...

The unfertilized ova of Persian sturgeon, Acipencer persicus, were stored in the ovarian fluid at 18 C and fertilized after 0 (control), 3, 6, 9 and 12 hours post stripping using fresh and N pooled sperm obtained from three males. In addition, changes in the osmolality and pH of ovarian fluid during storage were recorded. After 3 h of storage, no significant differences were found between ferti...