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King et al. (1999) provided empirical links between growth and thermal habitat for species occurring in lakes in Ontario. Years with warmer temperatures resulted in an earlier onset of stratification, a warmer epilimnion, larger thermal gradient, and shallower thermocline. On average, these variables accounted for 44% of the variation in fish growth. However, responses were species specific. For example, small - mouth bass (Micropterus clolomieui) showed increased growth rates, presumably as a result of increased availability of preferred growth temperatures in shal- low waters. Whereas, in the case of lake trout (Salve - linus namaycush), early stratification was suspected to promote earlier migration into deeper water and limit the length of spring feeding, thus reducing growth rates. These findings illustrate how climatic changes not only have the potential to directly influ- ence the availability of thermal habitats, but also may indirectly place constraints on feeding habitat avail- ability, with subsequent consequences on growth. 2 fur IF "I o"JpJ r °c e ',,halPlltges 11i" n Unlike projections for temperature, where consis- tency among models in local warming is high, less agreement exists among models regarding projected changes in precipitation for many regions (Meehl et al. 2007). Confidence in model projections of precipitation may vary depending on region and season. For example, confidence in precipita- tion projects is higher for winter and spring than for summer and fall (Karl et al. 2009). However, changes in the Southeast appear more difficult to project with confidence than some other regions of the United States (Figure 2 -4). The cross hatching in Figure 2 -4 indicates regions in which two - thirds of models agree on the direction of the mean change. Notice that the Gulf Coast states will tend to have less rainfall in winter and spring compared with the more northern states in the region, but the projected change for the mid - Atlantic states is generally small and with less agreement among models (Karl et al. 2009). This is not to say that changes in precipi- tation have not already occurred in the Southeast. Across the region, average autumn precipitation has increased by 30 percent since 1901, while summer and winter precipitation has declined by approxi- mately 10 percent during this same period (Karl et al. 2009, Figure 2 -5). �' in lI;