Female snakes (of various species including ball pythons) are typically much better eaters; instinctively, they have to be, to have the mature body size to handle reproduction. I've noticed this same thing in the
rosy boas I've kept & raised for years also, but no difference among the various kinds of rat snakes I've kept & still keep...in fact that's one reason I enjoy them much more than BPs...they aren't fussy eaters.
If you're set on a BP, I'd choose a female too, & for that reason.

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Female snakes (of various species including ball pythons) are typically much better eaters; instinctively, they have to be, to have the mature body size to handle reproduction. I've noticed this same thing in the
rosy boas I've kept & raised for years also, but no difference among the various kinds of rat snakes I've kept & still keep...in fact that's one reason I enjoy them much more than BPs...they aren't fussy eaters.
If you're set on a BP, I'd choose a female too, & for that reason.