HELP! I fear I'm doing something horribly wrong!

[kckilgannon]

My first, second, and third guess is that he's just very hungry. This is the time of year when BP's really start pounding the food b/c most will stop eating during breeding season. Also, be glad he switched from mice to rats quickly, many "mousers" stay picky and simply won't touch a rat.

You said he got pre-packaged small rats from the store, so I'll assume F/T. If they were the "Arctic Mice" brand then their small rats are pretty danged small, I think 50 grams each is typical. So, I could see an adult male easily downing two of them and wanting more. Look on FB or CL for a local supplier who can sell you F/T mediums, and offer one of those each week.

For handling, I would avoid it for 2 days after feeding, give him time to digest. Otherwise, diving into his hide and hissing is defensive not aggressive behavior, it just means he's happy and comfortable in his "house" and doesn't want to be messed with.

ETA: Do you have a thermostat regulating that UTH?

The thing is that he has never exhibited this sort of behavior. He's never been afraid of me picking him up, and he seems terrified now. Is it possible for him to become unsocialized due to the lack of handling, even if he's been handled often his whole life before now?

Also, there is no thermostat for the UTH. He has used the same one his whole life, and it still feels like it's working/same temp. as far as I can tell. I'm thinking I need to completely overhaul his tank supplies.