Common Map Turtle

Here's a turtle I haven't shown before, though for uncommon reasons. The Common Map Turtle (aka Northern Map Turtle) is considered to be fairly abundant around here and readily basks in the sun. It is considered difficult to spot/photograph though, since they are considered one of our more "wary" turtles - it doesn't take much to trigger them to dive into the water and away from danger (perceived or real).

The Common Map Turtle gets its name from the lines on its carapace. They look sort of like the contour lines on maps that delineate elevation. Unfortunately these marks fade as the turtles age. But I'd argue that the lines on the head/neck/legs also look like contour lines, and these are pretty prominent in my picture.

The female Common Map Turtles are nearly twice as big as the males, so if you ever find yourself saying "Wow - look at the size of that map turtle!" you're probably looking at a female. As some reptiles do, their gender is determined by temperature; the hotter it was during incubation, the more females there will be. (I do wonder if climate change might throw off the optimal male/female ratio.)

May 11, 2022 at the Delaware Raritan Canal
Photo 199459413, (c) jpviolette, some rights reserved (CC BY-NC)


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