The Tennessee Wildlife Resources Agency (TWRA) has introduced rainbow trout Oncorhynchus mykiss into five typically warm water streams in Dekalb and Warren Counties, Tennessee. These introductions are made as frequently as three times annually to support put and take fisheries, but the post-stocking status of these fish has not been evaluated, and any over-summer survival has not been considered significant. However, other studies in these watersheds have reported large rainbow trout (> 400 mm), which suggest that some of these introduced fish are surviving elevated summer water temperatures. Also, rainbow trout have been reported in streams that are tributaries to the stocked streams, indicating that the stocked fish are expanding their distribution. In addition, several fingerling rainbow trout have been collected during the spring months, and TWRA only stocks fingerlings in September, suggesting that natural reproduction may be occurring.