Map Turtles Care Sheet
Preparing an aquarium for map turtles:
All the map turtles (genus Gratemys) are quite aquatic; they like lots of water and bask less often than the "basking turtles" i.e. sliders, cooters & painteds. You should still provide a basking area with a basking light, but it would not need to be a large area, maybe just one corner ledge. Even a tiny Gratemys is a skilled swimmer and diver who would appreciate deeper water. A pile of rocks on which to rest and occasionally bask is sufficient. Your turtle may appreciate a second small climb-out area, perhaps a floating log-island. Also, these turtles will enjoy a ledge that is under water, but close enough to the surface to easily reach air with just the nose. In the wilds, maps and sawbacks live in heavily vegetated rivers, so they may appreciate some aquatic plants in the captive environment. Your aquarium set-up should include a full-spectrum florescent light, such as Reptisun or Reptile D-Light. Turtles get vitamin D3, which is required in order to utilize calcium, from the sun or full-spectrum reptile light. Although your little map or sawback might not use the basking areas often, he still will derive psychological benefits from the warmth and light of an incandescent bulb.
Filtration and substrate:
There are a variety of choices to be made in how to set up your aquarium and filter. Some people feel strongly that gravel should not be used. While it certainly isn't required, I haven't found it difficult to keep clean. It is normal, and may be helpful, for turtles to eat a small amount of substrate. If you use an undergravel filter, it may be used with a high quality canister type filter (e.g. Magnum 350, Eheim or Fluval.) These will do a good job of maintaining water quality without an excessive amount of work. Biological filtration will occur under the gravel, so an additional Bio-Wheel is not necessary. This link has an example and explanation of this type of setup.
The addition of aquatic plants will also help maintain water quality. Most turtles are not particularly sensitive to water quality and a little build up of ammonia won't harm them. Map/sawbacks are the exception. Young maps are especially sensitive to poor water quality, so attention to ammonia level and pH is extremely important with this genus. Water test kits are available at aquarium stores.
Feeding Map turtles:
Gratemys have broad crushing surfaces on their jaws, an adaptation for crushing hard-shelled creatures such as snails and crayfish. They also eat a wide variety of insects. Prepared turtle foods for semi-aquatics, such as Tetra's Reptomin or Wardley's Reptile T.E.N. provide good nutrition but should be supplimented with "meat" such as crickets or snails. Freeze-dried shrimp can be bought in some pet stores and these would provide some of the same nutritional value as the crayfish of their natural diet. They will also eat a small abount of vegetation, especially as juveniles. In the wilds, turtles gnaw on carrion bones and eat egg shells from a variety of aquatic birds to get the large amount of calcium required by turtles. You can replicate this by providing cuttlebone at all times. Some keepers attach it to the side while others let it float in the water. Some of us scrape off the brittle backing, while others feel the chance of injury is very small.
Two images from Bartlett & Bartlett
Mississippi Map Turtle, Graptemys (pseudogeographica) kohni
Black-knobbed Sawback, Graptemys nigrinoda
Information Sources:
Bartlett, R. D. 1998. Notes From the Field: Notes on Ringed and Other Map Turtles. Reptiles, Vol. 6, No. 5, 76-81.
Bartlett, R. D. & Bartlett, Patricia P. 1996. Turtles and Tortoises: A Complete Pet Owner's Manual. Barron's Educational Series, Inc. Hauppauge, N.Y. (This inexpensive book is one of the best in its price range. It can be purchased at amazon.com.)
Dampier, Louis. 1998. Map Turtles: An American Specialty. Reptile Hobbyist, Vol. 4, No.3, 36-44.
Ernst, C. H., Lovich, Jeffrey E. & Barbour, R. W. 1994. Turtles of the United States and Canada. Smithsonian Institution Press. Washington, D.C.
Smith, Hobart M. & Brodie Jr., Edmund D. 1982. A Guide to Field Identification: Reptiles of North America. Golden Press. New York, N.Y.
Also see:
An Overview of the Map Turtles of the United States, by
David T. Kirkpatrick, Ph.D, 1993.
Status
and Conservation of Graptemys barbouri, Graptemys flavimaculata,
Graptemys oculifera and Graptemys caglei by Greg George