The northern map turtle is known for its raised spikes along its shell, its secretive nature and devoted following. Read this quick guide for more.
Common Name: Common/Northern Map Turtle
Type of Eater: Omnivore (carnivorous when adult)
Size & Weight: 3-10 inches (females are much bigger than males)
Distribution: Northeast United States and Canada
Unique Feature: Raised ridge that sits on the top-middle of their shell
Map turtles get their name from their distinctive lines which mark the scutes on their upper-shell (plastron), which makes it seem as if their shell had a map drawn over it.
They are also easy to spot by their raised keel or shallow ridge that divides their plastron in half.
They have a rather devoted following, and are known for being somewhat rare to find in the wild. This is in part due to their very alert-style of basking. Older map turtles are generally very wary of strangers, and being quite strong swimmers, can quickly dart off when humans are in the area.
Common or Northern Map turtles are known for their extreme sexual dimorphism. Dimorphism refers to the differences between males and females of the same species. With the northern map turtle, this specifically is referring to its size.
Adult females can reach sizes of 6-10 inches, and males generally about half of that, from 3-5 inches.
Map turtles are what are known as ‘classic basking turtles’ in that they possess oval shells, webbed feet, medium tail, and a blunt nose.
In hatchlings and male map turtles, their oval shell has a raised keel or ridge that cuts its shell in half. With hatchlings and males, this keel usually has somewhat pronounced spikes. However, in females, the ridge is much less pronounced.
In terms of color, their heads, feet, and legs are often striped with yellowish thin bands that cover their dark skin.
Their shells are often darker greens, browns, and blacks.
Males tend to reach sexual maturity in about half the time (4-5 years) than females (10 years) do.
There are 11 species of map turtle within the United States. Of them, the common map is by far the most widespread of all species.
These turtles can be found in and near places with large bodies of water, in particular rivers, lakes and large streams. They are less likely to be found in or near smaller bodies of water such as ponds or creeks.
As opposed to species such as painted or red-eared sliders, who can be found traveling long distances over land, map turtles prefer to move around by water instead.
Although they prefer larger bodies of water, they tend to live out their lives around things such as fallen trees, floating branches and other types of debris that can be used as basking platforms.
Map turtles are very different from other common types of pet turtle in a very unique way. When young they munch on plant matter and are primarily herbivorous.
However, as they grow older they become more and more carnivorous.
As they mature, their jaws become quite powerful, which aids them in catching and eating things like snails, crayfish, mussels, and aquatic insects.
In captivity, however, they can be quite prone to overeat and indulge in things like frozen shrimp, krill and fish. An excessively protein-rich diet in captivity can lead map turtles to a premature death.
As such, it’s best that the bulk of their diet comes from a good, commercially-made pet turtle food. Supplement in smaller portions foods such as frozen krill, shrimp, bloodworms and other protein-rich foods.
Although map turtles are primarily carnivorous, they should also be given leafy-green vegetables often. Romaine lettuce is generally a good choice.
Unlike other common pet turtles such as sliders, map turtles, in general, are typically not as ‘hardy.’
For starters, they often require larger aquariums. This is why they are sometimes better off being placed in an outdoor pond or enclosure with lots of wide space. This type of environment best mimics their natural living habitat.
Because they require larger spaces to swim, they can become very aggressive towards other turtles if they are placed in smaller turtle tanks or aquariums. So, it may be best practice to separate any map turtles that you have.
Lastly, map turtles are known to be very problematic when the quality of the water they are in is low. If they are in an indoor aquarium or outdoor pond, make sure that the water quality is as clean and pure as you can get it. Again, the goal is to mimic their natural, native environment as much as possible.
When the water quality gets too low, map turtles can easily develop fatal diseases such as shell rot or shell fungi. If this happens, ensure that the water temperature is not too cold or hot (72-80 degrees), that it’s free of debris and clear, and that they are able to easily bask in a UVB lit area.
For more information on taking care of pet turtles, check out this article here: