Well typically you can feed 10-15% of their body weight so a 208 gram animal like yours can handle a 31 gram animal even if that's on the big side of the range. You'd be surprised how much they can handle. It typically surprises new keepers. Now I'm new as well. I've had my snake for about 5 months. But I've worked with an adult male bp for a while and garter snakes before that. It's definitely a sight to see them eat a big prey item. Now if you get the bigger ones I'd definitely weigh them and sort them so you have a bag of big ones and a bag of smaller ones. You might even be able to make a note with your order that you'd prefer the smaller ones but I'm pretty sure your snake will gain enough weight to eat the smaller ones then be ready for the bigger ones when you get to those.
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