Statement of Problem: Sturgeon (lake, pallid, and shovelnose) in Missouri waters have experienced population declines over the past century due to a variety of reasons including habitat change, exploitation, and others. The Missouri Department of Conservation (MDC) and other stakeholders have initiated monitoring programs to track trends in populations and to gauge success of harvest restrictions, stocking programs, and habitat improvements. As part of these monitoring activities, the MDC has assessed the levels of contaminants in shovelnose sturgeon fillet and egg tissue. Polychlorinated biphenyl (PCB) levels from that study were sufficiently high in eggs from certain portions of the Missouri and Mississippi Rivers, to warrant the Missouri Department of Health and Senior Services to issue a "do not consume" fish advisory for eggs in Missouri. This warning is triggered when concentrations of PCBs exceed 2,000 parts-per-billion (ppb). In addition to the human health concern, there are significant concerns on the reproductive health of fish with levels exceeding about 200 ppb of PCBs in fish gonads. Some of the effects linked to high gonadal PCB levels include delayed gonad maturation, hermaphrodism, and progeny survival. In samples where high levels of PCBs were observed, there tend to be high levels of chlordane and several other industrial pollutants. Therefore, additive or other interactive effects are possible. Currently, MDC and others have management programs designed to maintain and/or recover sturgeon populations. Based on the available information, it is plausible that the high levels of PCBs and some co-occuring contaminants could affect shovelnose sturgeon reproductive success. This research seeks to provide information on the likelihood that reproduction of shovelnose sturgeon populations is adversely affected by PCBs or co-occurring contaminants in the Missouri and Mississippi Rivers.
Objectives: To determine if concentrations of PCBs and co-occurring contaminants in gonads of field collected shovelnose sturgeon occur at concentrations that can interfere with fertilization, hatching and fry survival.