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...

This study documents changes in contamination over time at seasonal, interannual, and decadal time scales for sport fish collected in San Francisco Bay. Samples from seven fish species were prepared according to common consumption practices (muscle fillets either with or without skin) and analyzed for trace metals (mercury and selenium) and trace organochlorine contaminants (PCBs, DDTs, chlorda...

Two studies were conducted using 5to 6-month-old juvenile (mean weight: 3-4 g) white sturgeon, Acipenser transmontanus, to examine the cffects of density and other stressors on manifestation of disease caused by the white sturgeon iridovirus (WSIV). In the first study, replicate groups of Snake River white stur con 5 . were stocked at three densities (953, 1,907, and 3,178 fishlm ) In 0.3 I-m3 ...