The top figure shows survival from release to the ocean as a function of river flow. Flow is the mean daily flow at Bonneville averaged for the week of release. Kelt steelhead survival is positively related to flow. Survival as a function of temperature doesn’t show much of a relationship. Instead it appears that survival varies with temperature until a critical level is reached and then survival drops way off. Somewhere between about 14 and 18 C is the critical point.