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<br />. <br /> <br />. <br /> <br />Attachment 1 <br />(From Valdez et.al. 1987) <br /> <br />In addition to agreeing on the 18 curve sets, and providing qualifiers and <br />constraints for each, the experts developed a 'General Habitat Constraint' to be <br />applied to curves. This constraint was developed because the experts noted that <br />certain habitats (see items 1 and 2 below) cannot be modeled by IFIM without <br />intensive data collection efforts. Other workshop participants, with recognized <br />expertise in IFIM, stated that these habitats can be modeled, but have not been <br />modeled to date. Nevertheless, the experts decided that a curve set should not be <br />used with current PHABSIM analysis if it meets anyone of the following three <br />conditions: <br /> <br />1. 25 percent or more of data for the curve came from backwaters, <br />concavities, isolated pools, embayments, and gravel pits; or <br /> <br />2. 50 percent or more of the data came from eddies; or <br /> <br />3. 60 percent or more of the data came from a combination of items 1 and 2 <br />above. <br /> <br />To aid the user of this document in determining which curve sets the experts <br />recommend not using, because of the General Habitat Constraint, a habitat histogram <br />is presented for each curve set. This histogram and associated documentation reveal <br />the distribution and percentage of habitat types from which the depth, velocity, and <br />substrate data originated (i.e. in curve set 1, of all the habitats sampled, 88.94% <br />of the fish were collected in backwaters). Conditions 1 or 2 of this constraint <br />apply to 8 of the 18 final HSI curve sets. This means that the species experts do <br />not recommend using the indicated 8 curve sets with current PHABSIM analysis. <br /> <br />A.I.I <br />