Contaminants in Missouri River pallid sturgeon

Status of knowledge of the Pallid Sturgeon (Scaphirhynchus albusForbes and Richardson, 1905)

“…To date, few studies have measured environmental contaminant concentrations in PS. Tissue samples taken from three GPMU PS and 13 other PS, mostly collected from the CPMU, had metals (mercury, cadmium, and selenium), PCBs, and organochlorine pesticides (chlordane, DDT, DDE, and dieldrin) at concentrations of concern (Ruelle and Keenlyne, ; Ruelle and Henry, ). In at least two instances individual PS have been observed with both female and male sex organs (DeLonay et al., , ) a condition that may be associated with high levels of endocrine‐disrupting contaminants (Harshbarger et al., ).…”

Kemp's Ridley Sea Turtle Saga and Setback: Novel Analyses of Cumulative Hatchlings Released and Time-Lagged Annual Nests in Tamaulipas, Mexico

“…Heavy metals and organochlorine compounds accumulate in sturgeon tissue, but their long-term effects are not known (Ruelle and Henry 1992;Ruelle and Keenlyne 1993). Elevated levels of contaminants, including chlorinated hydrocarbons, in several other fish species are associated with reproductive impairment (Cameron et al 1992;Drevnick and Sandheinrich 2003;Hammerschmidt et al 2002;Longwell et al 1992), reduced egg viability (Billsson et al 1998;Giesy et al 1986;Mac and Edsall 1991;Matta et al 1997;Von Westernhagen et al 1981), reduced survival of larval fish (Berlin et al 1981;Giesy et al 1986), delayed maturity (Jorgensen et al 2004) and posterior malformations (Billsson et al 1998).…”

Field endoscopy for identifying gender, reproductive stage and gonadal anomalies in free-ranging sturgeon (Scaphirhynchus) from the lower Mississippi River

“…Mortality of both species is greater in the middle Mississippi River, which is commercially fished, than in the lower Mississippi River, most of which is closed to sturgeon fishing (Morrow et al., 1998; Colombo et al., 2007a,b; Killgore et al., 2007a,b). Both species are impacted by contaminants, associated with the occurrence of hermaphroditic or intersexual individuals, so that concern exists for reproductive health of the sturgeon (Ruelle and Keenlyne, 1993; Harshbarger et al., 2000; Koch et al., 2006). Larvae of pallid sturgeon and shovelnose sturgeon co‐occur (Engineer Research and Development Center, unpubl.…”