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TO: Pallid Sturgeon Condition Assessment Authors,MRRP Integrated Science Program <br /> Leadership, and MRRIC <br /> FROM: Independent Science Advisory Panel (ISAP) <br /> RE: ISAP Comments on Draft Pallid Sturgeon Condition Assessment <br /> DATE: October 12, 2016 <br /> NOTE: This memo builds on and reemphasizes comments provided by ISAP during the Pallid <br /> Health Assessment Report Webinar on September 29, 2016. It reflects ISAP thoughts subsequent <br /> to webinar discussion and an ISAP phone discussion October 6. These comments address both <br /> the assessment and the "new information"process. <br /> Concern regarding low body condition of pallid sturgeon in the Missouri River was expressed by <br /> biologists for Nebraska Game and Parks after their inspection of fish collected during recent <br /> sampling activities. The MRRP science leads responded to that concern following the pilot <br /> procedure for"new information" outlined in the draft AM Plan by directing the pallid sturgeon <br /> Effects Analysis Team to convene an issue team that would assess whether a"skinny fish" <br /> phenomenon(a troubling occurrence of fish with lower than expected body condition)was <br /> occurring in the lower river, and its likely cause or causes. Guiding questions were posed to the <br /> issue team from the MRRP—Is there evidence that pallid sturgeon in the lower Missouri River <br /> are in poor and/or declining condition? And, what is the likely cause of the poor condition?Each <br /> question also asked what is the level of uncertainty in the conclusion? <br /> The ISAP appreciates the efforts of Randall et al. (2016)to explore quantitatively the reported <br /> "skinny fish"phenomenon. However,the panel is not convinced that the most appropriate <br /> methods for assessing the available data were used in developing the results presented in the <br /> draft report. Correspondingly,the panel concludes that the reported analyses do not <br /> unequivocally substantiate the existence of a"skinny fish"phenomenon for pallid sturgeon in the <br /> lower Missouri River. The absence of a significant population-level trend in the body condition <br /> of pallid sturgeon in the lower river and the observation that river-segment and year effects <br /> might explain the occurrences of pallid sturgeon in low condition indicate that the analytical <br /> method presented in the report does not accurately characterize deviation from a baseline <br /> "healthy" condition. <br /> The analyses presented in the draft report suggest that pallid sturgeon body condition has <br /> declined system-wide (see Figures 7 and 8), and particularly in river segment 9. That suggestion <br /> is based on application of the Shuman et al. (2011) K„formula as a reference model for pallid <br /> sturgeon body condition. The Shuman et al. model was constructed from data on 2,268 pallid <br /> sturgeon collected from 1998-2007. It is possible that the system-wide body condition of <br /> >12,000 pallid sturgeon that measured between 200 and 1200 mm FL in the current analysis does <br /> not fit the Shuman et al. model. That is, the model does not accurately reflect the length-weight <br /> relationship for pallid sturgeon throughout its range in the Missouri River, because of the limited <br /> 1SAP Comments on Draft Pallid Sturgeon Condition Assessment Page 1 of 4 <br />