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During the summer of 2000, 397 3 -year old hatchery- raised pallid sturgeon and 6 adult brood stock <br />pallid sturgeon were taken from the Gavins Point National Fish Hatchery and released into the Fort <br />Randall reach of the Missouri River (Segment 9). All of the pallid sturgeon had tags and transmitters <br />for identification and telemetry purposes, 22 juveniles were fitted with sonic transmitters. <br />Despite stocking efforts, pallid sturgeon remain rare compared to the shovelnose sturgeon. In 1997 <br />and 1998, the MDC, Long Term Resource Monitoring Station at Cape Girardeau collected 7 pallid <br />sturgeon (0.45 percent) compared to 1549 shovelnose sturgeon in the middle Mississippi River <br />(Petersen 1999). All seven were hatchery-origin pallid sturgeon Q. Grady, pers. comm. 2000). <br />Constant et al. (1997) noted that in surveys of commercial catch, shovelnose sturgeon accounted for <br />between 52 percent and 98 percent of the total sturgeon catch, with the remainder composed of similar <br />portions of hybrids (2 percent to 21 percent) and pallid sturgeon (0 percent to 26 percent). <br />Evidence of successful pallid sturgeon reproduction and recruitment is rare throughout the range of the <br />species, because of fragmentation and modification of the habitats. In 1998, the MDC collected a <br />young -of -the -year pallid sturgeon at approximate river mile 49.5 south of Cape Girardeau in the middle <br />Mississippi River (Petersen and Herzog 1999). During the summer of 1998 and 1999, several pallid itV16b <br />sturgeon larvae were collected from the lower Missouri River in Missouri (Jim Milligan, USFWS, pers. (t <br />comm. 1999). Those three instances represent the first evidence of successful pallid sturgeon <br />reproduction in recent years and indicate that some suitable spawning habitat and hydrologic conditions �" L <br />_ remains in the lower Missouri River below Gavins Pont Dam and/or Platte River, and potentially, the <br />$ <br />middle Mississippi River. L ` <br />no eo,dk»a <br />Recent work in the Atchafalaya River has revealed fish of several age groups suggesting that some <br />reproduction and recruitment may occur in the Atchafalaya River. However, the only physical evidence <br />of reproduction were three gravid females (Constant et al. 1997). According to their data, pallid <br />sturgeon collected in the Atchafalaya River and other areas of the Mississippi River have averaged less <br />than 6.6 lbs (3 kg) and length -at -age estimates calculated according to Fogle (1963) indicated that <br />even the smallest fish were over age 6, with the oldest perhaps over age 14. The age of fish in their <br />study indicates the most recent recruitment of pallid sturgeon to be from the 1988 year class (Constant <br />et al. 1997). <br />Larval sturgeon rarely have been collected from within the range of pallid sturgeon. This may be due to <br />low reproductive success or the inability of standard sampling gear to capture larval sturgeon. Hesse <br />and Mestl (1993) collected two sturgeon larvae from the Missouri River adjacent to Nebraska between <br />1983 and 1991. Those larvae were among 147,000 fish larvae collected during filtration of <br />18,340,014 cu ft (519,400 cu m) of river water. Gardner and Stewart (1987) collected no sturgeon <br />larvae in 339 samples from the Missouri River or in 77 samples from tributary streams where 3,124 and <br />5,526 fish larvae were collected, respectively. In three years of sampling in/near Lisbon Chute on the <br />Missouri River, the Service's Columbia Missouri Fishery Resources Office collected over 10,000 small <br />106 Status Range Wide -PS <br />