Northern map turtles boast large heads and strong jaws that allow them to consume mollusks like snails and Asian clams, along with crustaceans such as crabs, insects and aquatic insect larvae from Trichoptera (caddisflies) and Ephemeroptera (mayflies).
This medium-sized semi-aquatic reptile can be found in rivers, large streams, ponds and lakes across the northeastern quadrant of the United States. Their olive green to brown shells are marked by thin yellow lines for added ornamentation.
Contents
Adults
The adult common map turtle (Graptemys geographica) is an aquatic species with large and moderate-sized bodies that is typically olive to brown in colour and bears an intricate map-inspired carapace design with pairs of circles connected by lines resembling roads on a map. The margin has a light reticulate pattern while its front often displays serrated or slightly keeled teeth, and often sports an indented face resembling roads from a map. A characteristic ‘Y’ shape on their heads extends from postorbital blotches onto head with an indented line curving upward around their neck (vaguely frog-faced).
Wild diets vary by gender; adults are usually molluscivores, eating snails, clams and other mollusks found locally as well as aquatic insects such as aquatic insects. Their mouths feature wide jaws with strong jaw-locks that enable them to crush up these creatures effectively; adult males, on the other hand, often feed on aquatic insect larvae such as those found on trichopterans, mayflies and dragonflies as well as other types of aquatic insects; their diet is much more varied in captive environments than their counterparts in wild environments.
Juveniles
Northern map turtles make excellent beginner turtles for large aquariums or garden ponds that can provide year-round housing (although they prefer deeper waters, as shallower warmer waters can lead to shell rot/skin fungus). While mostly carnivorous, they do consume some vegetation such as Anacharis. When threatened, they retreat into their protective carapace scutes for protection and when fed too many high-protein foods such as crayfish, feeder fish, earthworms crickets or blood worms which leads to rapid growth & pyramided shell formation; avoid this as soon as possible!
Northern Map Turtles can be identified by their distinctive blunt head, peripherally placed yellow eyes with an amber bar across their pupils and curved lower neckline. Furthermore, there is plenty of yellow striping against dark skin as well as an F or C shape in their neck area; healthy captive-bred specimens typically reach SCL sizes of around 5 inches.
Nesting
The northern map turtle, more commonly known as the common map turtle, is one of the most widespread species. Its olive to brown carapace features delicate yellow lines resembling topography on maps.
An omnivorous species, they feed during the day in shallow water environments. Adult females preferentially consume snails and Asian clams while males feed on aquatic insects; both may consume other sources like dead fish, plant material or even crayfish.
These turtles nest in sandy soil and can produce two clutches in any breeding season, laying between six and 20 eggs each summer that hatch 50-70 days later (typically female but occasionally males can appear due to cooler temperatures). Common map turtles can be found throughout their range including rivers, sloughs, and oxbow lakes; preferring open bodies of water over isolated ponds and creeks where they tend to flee when approached.
Care
Keep Northern Map Turtles relatively easily provided you have the appropriate habitat. In captivity, they tend to be active swimmers that frequently explore their tanks openly – if yours starts hiding or refusing food this could be a telltale sign they don’t feel well!
In the wild, they inhabit wide rivers with clay or sandy bottoms and oxbow lakes with open areas for basking and aquatic vegetation. Omnivorous in nature, they feed on snails, clams, fish, crayfish and aquatic plants as food sources.
In the wild, they face threats such as water pollution and waterfront development that destroys breeding sites, car strikes and fishing hook hooks; their numbers have declined considerably and some states list them as endangered species. Adult males can be distinguished from females by the distinct keel pattern on their carapace with large knobs protrusions protrusion up from it and large knobs protruding straight up from it – easily distinguishable.
