If the tortoise is too big to lift above your head, try lifting it just slightly off the ground. Then, get down low enough to see underneath it.
If the plastron is indented, or concave, it is most likely male. The concave plastron helps the male to more easily mount the female. If the plastron is flat or convex, it is most likely female. A flat or bulging plastron helps the female carry more eggs.
A male’s anal scute usually forms a wider, more open angle, with the points farther from the marginals to allow the tail to move freely. A female’s anal scute will form a tighter angle, with points close to the marginals. This offers her more protection.
Males are usually smaller than females, too. Red-footed tortoises are an exception. In this species, the males are generally the same size as the females.
Male hinge-back tortoises have more elongated bodies, while the females are rounder. Male Hermann’s tortoises will be a little bit wider at the rear than the females of the same species.
Determining sex by the tail length is great for tortoises that you cannot pick up for whatever reason.
A female’s tail is usually shorter than the end of a cotton swab. A male’s tale will be longer than that, but still not huge.
If you know the species of the tortoise, look up pictures of that specific species for accuracy.
If you choose to bring in a photo, make sure to photograph the tail and the lower shell of the tortoise, as those are the most obvious indicators of a tortoise’s sex.
