Follow Pearl, Malti & Bruce
One of the first tasks I faced after I rescued Bruce and he joined our little flock was to figure out if he was a girl box turtle or a boy box turtle.
This was an especially pressing issue, since my 17-year-old parrot, Pearl, had spent a whopping 11 of his 17 years to date as a girl bird.
In fact, it wasn’t until my mom bought us a membership in the National Cockatiel Society that we discovered he was a boy bird (you can read more about this in our biography book, Love & Feathers).
But back on topic….turtle gender can be notoriously difficult to sleuth out.
Most turtles won’t even start to show gender-specific signs until they reach a certain age or a certain length (for box turtles, that is usually around 5 to 7 years old or after they grow to at least 3.5 inches long).
In the meantime, looking at a box turtle’s coloration can sometimes offer some helpful clues.
For instance, male 3 toed box turtles usually have bright, colorful eyes and patterns on their head and/or neck skin, while female 3 toed box turtles tend to be more muted in both areas.
But the best way to tell a boy box turtle from a girl box turtle is to wait until they have reached the requisite age/length and look in two areas: shell underside (plastron) and tail.
A boy 3 toed box turtle will have a bit of concavity or indentation that curves inward towards the middle/back of the plastron. A girl 3 toed box turtle won’t have that – her plastron will be straight and smooth.
Also, a boy box turtle will have a longer tail with the cloaca (opening) farther down on the tail. A girl box turtle will have a shorter tail with the cloaca closer to her shell.