List off the biggest mistakes new ball python owners make?

[Bogertophis]

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Currently I'm feeding her rat pups; I feed her prey that's either the same size as the widest part of her body OR something slightly larger.

Is this a good way to decide prey size without a scale? Thank you all for answering my questions!

Also, would it be a good idea to give her more variety; chicks, quails, baby rabbits etc.

Obviously rats would be her main diet but I don't want her to have a deficiency in certain nutrients and or too much of another one.

I'd suggest feeding nothing wider than her mid-body- no need to push food, & sometimes when BPs are fed larger items than they need, they seem MORE likely to go on fasts, which is a pain.

Some snakes accept a wide variety of prey easily, but BPs are not known for that- they tend to be picky eaters, sometimes even to the point of wanting the same color rodent, so personally I'd stick with what works. If she's eating rats, stick with rats, & don't worry about it. Or, "if it ain't broke, don't fix it"!

If you feed something else now, she may then decide to refuse rats & insist on the new food. BPs can be quite finicky, perhaps because these are not their normal prey in the wild but rather domestic animals more readily available fed in substitution.

If you want to feed her natural diet, that would probably be ASFs (African soft-furred rodents) but they're harder to come by because they're harder to breed & therefore more expensive. Think carefully before you switch, & do some research- depending on where you live, they may not even be legal to buy. Check prices with online sources- & consider what you'd do if they went out of business or stopped shipping to your location for any reason. Personally, I'd stick with rats.