Appendix 15. Model user interface for sketching hypothesized relationships between physical habitat factors (rows of graphical display matrix) and survival/growth components of the vertebrate populations submodel. The first column of display matrices allows users to define relationships between habitat factors and physical size of “foraging arenas” used by juvenile vertebrates (sketching a positive relationship implies that the habitat factor has a positive effect on “carrying capacity” for juveniles). The second column defines how habitat factors moderate/exaggerate juvenile survival effects of the risk ratio (predators)/(food); in this case, positive relationships imply increasing predation risk and/or reduced food availability (leading to lower survival) as the habitat factor increases. The third column defines effects of habitat factors on body growth rates of older (age 1 yr+) animals; it is used mainly to model effects of temperature and turbidity on body growth of species such as rainbow trout.