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Definitions of life cycle stages: Wildhaber et al. (2007) developed a conceptual life <br />history model to organize the stages which are important to consider as studies of pallid sturgeon <br />proceed. In addition, in this model, transition probabilities are used to describe the impacts of the <br />spectrum of conditions in the environment which influence the survival of a pallid sturgeon from <br />one life stage to the next. We present information pertaining to major categories included in <br />these transition probabilities (i.e. mortality factors, habitat, water quality) in subsequent sections <br />of this report. <br />Gametes: The production of viable gametes by adult fishes is their contribution to <br />the next generation. The eggs and sperm from the adults provide the genetic basis upon which <br />the next generation depends. The fertilized eggs of sturgeon sink and adhere to the substrate <br />(Simpkins and LaBay 2007). These gametes need to be deposited in a suitable environment <br />which allows their development into embryos. The use of egg mats at suspected spawning sites is <br />a valuable sampling technique to detect the presence of spawning (Laustrup et al. 2007; <br />Simpkins and LaBay 2007). <br />Embryos: <br />The embryo life stage is divided into two segments (pre and post hatching). Both of these stages <br />are dependent upon the food resources in the yolk for development. Prior to hatching, the <br />embryos adhere to the substrate where the eggs were deposited during spawning. After hatching, <br />the embryos drift downstream with the water currents (Kynard et al. 2002; Kynard et al. 2007). <br />The period of drift may carry them for over 300km downstream from their point of hatching <br />(Kynard et al. 2007). The distance drifted during the post-hatching embryonic phase may be