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harvested in all states on the Missouri and Mississippi Rivers (Helms 1974). The larger lake and pallid <br />sturgeon were sought for their eggs which were sold as caviar, whereas shovelnose sturgeon were <br />historically destroyed as bycatch. Commercial harvest of all sturgeon has declined substantially since <br />record keeping began in the late 1800s. Most commercial catch records for sturgeon have not <br />differentiated between species and combined harvests as high as 430,889 lb. (195,450 kg) were <br />recorded in the Mississippi River in the early 1890s, but had declined to less than 20,061 lb. (9,100 kg) <br />by 1950 (Carlander 1954). Lower harvests reflected a decline in shovelnose sturgeon abundance since <br />the early 1900s (Pflieger 1975). Today, commercial harvest of shovelnose sturgeon is still allowed in 5 <br />of the 13 states where pallid sturgeon occur. <br />Mortality of pallid sturgeon occurs as a result of illegal and incidental harvest from both sport and <br />commercial fishing activities (Bob Sheehan, Southern Illinois University, pers. comm.). Sturgeon <br />species, in general, are highly vulnerable to impacts from fishing mortality due to unusual combinations <br />of morphology, habits and life history characteristics (Boreman 1997). In 1990, the head of a pallid <br />sturgeon was found at a sport-fish cleaning station in South Dakota, and in 1992 a pallid sturgeon was <br />found dead in a commercial fisherman's hoop net in Louisiana. In 1997, four pallid sturgeon were <br />found in an Illinois fish market (Sheehan et al. 1997b). It is probable that pallid sturgeon are affected <br />by the illegal take of eggs for the caviar market. In 1999, a pallid sturgeon that was part of a movement <br />and habitat study on the lower Platte River was harvested by a recreational angler (Dr. Ed Peters, <br />University of Nebraska - Lincoln, pers. comm. 1999). In addition, such illegal and incidental harvest <br />may skew pallid sturgeon sex ratios such that hybridization with shovelnose sturgeon is exacerbated. <br />Currently, only a sport and/or aboriginal fishery exists for lake sturgeon due to such low population <br />levels (Todd 1998). Shovelnose sturgeon is commercially harvested in eight states, including Illinois <br />and Missouri, and a sport fishing season exists in a number of states (Mosher 1998). Although <br />information on the commercial harvest of shovelnose sturgeon is limited, Illinois reported the <br />commercial harvest of shovelnose sturgeon was 43,406 lb. (19,689 kg) of flesh and 2331b. (106 kg) of <br />eggs in 1997 and Missouri reported a 52 -year mean annual harvest of 8,157 lb. (3,700 kg) of flesh <br />(Todd 1998) and an unknown quantity of eggs for 1998. Missouri also has a sport fishery for <br />shovelnose sturgeon but has limited data on the quantities harvested (Mosher 1998). <br />Pollution/Contaminants - Although more information is needed, pollution is likely an exacerbating <br />threat to the species over much of its range. Pollution of the Missouri River by organic wastes from <br />towns, packing houses, and stockyards was evident by the early 1900s and continued to increase as <br />populations grew and additional industries were established along the river (Whitley and Campbell <br />1974). Due to the presence of a variety of pollutants, numerous fish - harvest and consumption <br />advisories have been issued over the last decade or two from Kansas City, MO, to the mouth of the <br />Mississippi River. That represents about 45 percent of the pallid sturgeon's total range. <br />PCBs, cadmium, mercury, and selenium have been detected at elevated, but far below lethal, <br />concentrations in tissue of three pallid sturgeon collected from the Missouri River in North Dakota and <br />114 Status Range Wide -PS <br />