TRANSLATING RIVER HYDRODYNAMICS IN TO FISH POPULATION RESPONSES FOR USE IN MULTI-SCALE MODELING OF RIVERINE ECOSYSTEMS

The pallid sturgeon is rare throughout the Missouri River Basin and was federally listed as endangered in 1990 (Dryer and Sandvol, 1993). The shovelnose sturgeon historically was more common and widespread (Becker, 1983). Persistence and resiliency of shovelnose sturgeon in comparison to pallid sturgeon may be due to earlier maturity, lower trophic status, and adaptability to environmental conditions (Keenlyne and Jenkins, 1993). Understanding how climate change may differentially affect these two species may be useful to managing for their continued existence.

Wildhaber and others (2007) introduced a conceptual life-history model for pallid and shovelnose sturgeon. The model was developed to delineate how Scaphirhynchus sturgeon ecology relates to river management. This model provides an illustration of how climate may interact with management actions to affect species recovery. It provides the framework for expanding Bajer and Wildhabers’ (2007) population forecasting model to include environmental variables for prediction of future population size and distribution of Missouri River pallid and shovelnose sturgeon. Because sturgeon in large rivers may move long distances (DeLonay and others, 2007), a life-history model needs to incorporate use of different parts of the river, or its tributaries. For greatest utility in assessing habitat effects on population processes, the life-history model should accommodate fine-scale, three-dimensional models of habitat use and availability, and fish behavior, nested within a broader geographic extent.

On-going USGS Comprehensive Sturgeon and Research Program work on migration, physiology, habitat choice, and spawning success of shovelnose and pallid sturgeon provides data to inform such a model. River temperature and velocity distributions will be used within a sturgeon bioenergetics model. Although such models are based on first principles, they do include parameter estimates from the literature. We will not have local-scale information to update these parameters. However, we can accommodate such uncertainty by allowing values for these parameters to be uniformly distributed throughout ranges reported in the literature. The forcing uncertainties are accommodated through the distributions of river temperature and velocity from previous stages.

Bajer, P.G., and Wildhaber, M.L., 2007, Population viability analysis of Lower Missouri River shovelnose sturgeon with initial application to the pallid sturgeon: Journal of Applied Ichthyology, v. 23, no. 4, p. 457-464.

Becker, G.C. 1983. Fishes of Wisconsin: Madison, Wisconsin, University of Wisconsin Press, p. 1,053.

DeLonay, A.J., Papoulias, D.M., Wildhaber, M.L., Annis, M.L., Bryan, J.L., Griffith, S.A., Holan, S.H., and Tillitt, D.E., 2007, Use of behavioral and physiological indicators to evaluate Scaphirhynchus sturgeon spawning success: Journal of Applied Ichthyology, v. 23, no. 4, p. 428-435.

Dryer, M.P. and A.J. Sandvol. 1993. Recovery plan for the pallid sturgeon (Scaphirhynchus albus): Bismarck, North Dakota, U.S. Fish and Wildlife Service, p. 55.

Keenlyne, K.D. and L.G. Jenkins. 1993. Age at sexual maturity of the pallid sturgeon: Transactions of the American Fisheries Society, v. 122, no. 3, p. 393–396.

Wildhaber, M.L., DeLonay, A.J., Papoulias, D.M., Galat, D.L., Jacobson, R., Simpkins, D.G., Braaten, P.J., Korschgen, C.E., and Mac, M.J., 2007, A Conceptual Life-History Model for Pallid and Shovelnose Sturgeon: US Geological Survey, p. 189.