The CPUE for the 2019 sampling season dropped to 0.26 and represents a notable decrease compared to the 2018 season CPUE of 1.18. Juvenile sDPS green sturgeon tagged during the 2018 sampling season were mostly (78 percent) from the 2017 brood year. 2017 was a near-record water year which resulted in banner recruitment to the juvenile life stage. In contrast, CPUE in 2015, 2016, and 2017 was extremely low and is thought in part to be a result of poor recruitment to the juvenile life stage during the 2013-2015 drought. The 2018 water year was classified as below normal precipitation, which may have also resulted in lower recruitment of sDPS green sturgeon to the juvenile life stage and hence the lower CPUE observed in 2019 compared to 2018.
Table 1. Catch per unit effort (CPUE) as juvenile sturgeon tagged per sampling event, 2015 - 2019
seasons. One sampling event is approximately six hours of gill net deployment.
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