I am trapping in the summer in Texas. It is not my favorite time of the year to trap, but it is that time when you get get Moms who have recently weaned their kitties. Our main goal in trapping is to stop the cycle of ‘multiplication’, of course, so we deal with the heat the best way we can. I try to put a sheet over part of the trap to give the kitty and food shade. One thing that I have also learned is to try to keep ants out of the traps here in Texas during this heat. I put plastic down under the traps and I spread diatomaceous earth, food grade, all around the trap and the plastic. It seem to keep them out. Sadly, it does not work on flies, but the sheet over part of the trap could help.
In the use of DE (diatomaceous earth), I also find that it is good for worming. Worms are prevalent here during the summer. Once I have kitties in a trap, I like to use a little DE in their food and I try to go into that community, as a whole, once all have been neutered and use DE to worm. I mix it in moist food based on the suggestions on the container and then I go back 2 weeks later and do that again. I just read a suggestion from another trapper that sounded like a great idea. I have been trying, in communities were the cats are eating at certain times, to sprinkle a little DE on their bodies to try to decrease the flea problems feral cats have in the summer here. The suggestion was to put DE on any solid surface that maybe be used to feed them and add a little catnip to it. That way, the kitties will rub themselves in it, as kitties do. Sounds like it might work to me.