Ponduke, Blue tilapia die at ~45*, but in a pond situation, that is a little misleading. Blue Tilapia start getting lethargic ~58* as well as depressing their immune systems. With predators present, except for the largest, Blues are more likely to die from injury/infection/predation before the water temps drop to lethal levels. For LMB, Blues become an easy target when the LMB's metabolism has slowed allowing the Tilapia they gorge themselves on to turn into lipds rather than muscle. This allows the LMB to have greater fat stores to live on during the winter, resulting in less weight/flesh loss over the winter.
There are few "scientific" studies on tilapia outside of the food fish industry. Hopefully this fall that will begin to change. There are many reports and studies that are related to tilapia consuming what we call "muck"---detritus. It must be organic in nature and have nutients that are digestible though.
