BioKIDS home

Kids' Inquiry of Diverse Species

Barbour's Map Turtle

Graptemys barbouri

What do they look like?

Barbour's map turtles have dark brown or black skin with light yellow or green markings. They have broad heads with special patterns in yellow on the top of their head and behind their eyes. A light-colored bar on their chin goes around the curve of their jaw. The top of their neck, back legs, and tail have stripes. The shell on top of their back is like a big olive green dome with dark spines. The second and third spine are the biggest, but they wear down as the turtle gets older. The part of the shell that covers their belly is yellow and there is a black border at the edge of each section. (Ernst, et al., 1994)

Female Barbour's map turtles are much larger than males. The back shell of females is 15 to 33 cm long, and the back shell of males is 9 to 14 cm long. This means that females can be 3 times bigger than males. Their heads are wider too, and their lower jaw sticks out farther than their upper jaw. (Cagle, 1952; Orenstein, 2001)

  • Sexual Dimorphism
  • female larger
  • sexes shaped differently
  • Range length
    4 to 33 cm
    1.57 to 12.99 in

Where do they live?

Barbour’s map turtles live in the southeastern United States. They live in Alabama, Georgia, and the Florida panhandle, in and around the Apalachicola and the Chipola Rivers. (Cagle, 1952)

What kind of habitat do they need?

Barbour’s map turtles spend nearly all of their lives in large freshwater rivers that have limestone rock on the bottom. They only come out of the water to lay eggs or bask in the sun on big fallen branches. They prefer deeper water that flows faster compared to other turtles in their family. Females usually live in deeper water than males. Young Barbour's map turtles stay closer to the riverbank than adults. (Cagle, 1952; Ernst, et al., 1994)

  • Aquatic Biomes
  • rivers and streams

How do they grow?

Barbour's map turtle eggs have a shell that holds the developing turtle and a yolk sac. The baby turtles take 58 days to come out of the eggs. They look just like miniature adults when they're born, except that their colors aren't as bright. Their back shell is 37 mm long on average and weighs around 10.7 g. Whether the turtle is male or female depends on how warm the eggs are before they hatch. If the eggs are less than 25 degrees Celsius, only males are born. If the eggs are warmer than 30 degrees Celsius, only females are born. Males are able to have their own young when they are 2 to 4 years old, but females can't until they are 15 to 20 years old. This explains why females are bigger than males. Females also have bigger spaces in their shells that allow them to get bigger. (Cagle, 1952; Ernst, et al., 1994; Valenzuela and Lance, 2004; Wyneken, et al., 2008)

  • Development - Life Cycle
  • temperature sex determination

How do they reproduce?

Males attract females by approaching them with their neck stuck out, and then touching the sides of the female's head with the inside of their front legs for a few seconds. Scientists don't know much about how their mating systems work. (Ernst, et al., 1994)

Females dig out nests next to a stream or river with their back legs. After laying the eggs, females cover them with dirt and leave them to hatch. Their nesting season lasts from June through early August, but often happens in the winter in captivity. There are about 6 to 11 eggs at a time, but females can lay eggs up to 4 times in the same season. This means that females can lay 11 to 51 eggs in one season. Eggs are usually 3.71 cm long and 2.61 cm wide. (Cagle, 1952; Ernst, et al., 1994)

  • How often does reproduction occur?
    Barbour's map turtles breed annually, and females are capable of producing multiple clutches in a single mating season.
  • Breeding season
    Nesting season is June through early August.
  • Range number of offspring
    6 to 11
  • Average gestation period
    58 days
  • Range age at sexual or reproductive maturity (female)
    15 to 20 years
  • Range age at sexual or reproductive maturity (male)
    2 to 4 years

Like many reptiles, Barbour's map turtles do not put much time or effort into caring for the young. Females dig a nest and cover the eggs with dirt. Besides that, neither parents contribute to the survival of their young. (Buhlmann, et al., 2008; Ernst, et al., 1994)

  • Parental Investment
  • no parental involvement
  • pre-fertilization
    • provisioning
    • protecting
      • female
  • pre-hatching/birth
    • provisioning
      • female
    • protecting
      • female

How long do they live?

Scientists don't know much about how long Barbour's map turtles live in the wild. The record for the longest lifespan in captivity was 31 years, 8 months, and 9 days. This turtle lived at the National Zoo in Washington, DC. (Ernst, et al., 1994)

  • Range lifespan
    Status: captivity
    31 (high) years

How do they behave?

Barbour's map turtles spend most of their lives in the water, so they are good swimmers. Males spend more time in calmer water, probably because they are smaller. Barbour's map turtles spend a lot of time warming themselves in the sun, especially on limestone rocks, vines, or trees in or near the water. If there is a flood in the stream and river where they live, they move to the spot in the river with the weakest current. (Cagle, 1952; Ernst, et al., 1994)

Home Range

The area where Barbour's map turtles generally live and travel is 365 meters along the river for males and 273 meters for females. (Ernst, et al., 1994)

How do they communicate with each other?

Scientists don't know much about how Barbour's map turtles communicate or sense their environment. In courtship, males touch the faces of females with their front legs. (Ernst, et al., 1994)

What do they eat?

Barbour's map turtles are carnivores, so they only eat other animals. Females eat mostly snails and some clams. The crush their prey and swallow all of it, even the shells. Males don't eat as many snails or claims. They eat more insects and insect larvae. Young Barbour's map turtles also eat insects and insect larvae before they start to eat mollusks with hard shells. (Ernst, et al., 1994; Orenstein, 2001)

  • Animal Foods
  • insects
  • mollusks

What eats them and how do they avoid being eaten?

Barbour's map turtle eggs are eaten by snakes and terrestrial mammals like raccoons. Humans sometimes eat them as food. If they can't escape from predators, they withdraw into their shells or try to bite. (Ernst, et al., 1994)

What roles do they have in the ecosystem?

Barbour's map turtles are important predators of mollusks and they and their eggs get eaten by other predators.

Do they cause problems?

Barbour's map turtles aren't known to have any negative impacts on humans.

How do they interact with us?

Barbour's map turtles were used in the research that identified the cause of meningitis in humans, which is called Flavobacterium meningosepticum. Humans also eat them or sometimes keep them as pets. (Ernst, et al., 1994; Jacobson, et al., 1989)

Are they endangered?

Barbour's map turtles are considered "vulnerable" by the IUCN Red List and are listed on on Appendix III of CITES. Their global rank is "G2," which means that they are at risk. Barbour's map turtles live in a fairly small area. They are threatened by damage to their habitat, which can come from from machines moving sand from the bottom of the river, interfering with the flow of water, or pollution. (van Dijk, 2012)

Contributors

Gina Vasseur (author), The College of New Jersey, Keith Pecor (editor), The College of New Jersey, Tanya Dewey (editor), University of Michigan-Ann Arbor, Catherine Kent (editor), Special Projects.

Glossary

Nearctic

living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.

World Map

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends.

carnivore

an animal that mainly eats meat

diurnal
  1. active during the day, 2. lasting for one day.
drug

a substance used for the diagnosis, cure, mitigation, treatment, or prevention of disease

ectothermic

animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature

fertilization

union of egg and spermatozoan

food

A substance that provides both nutrients and energy to a living thing.

freshwater

mainly lives in water that is not salty.

heterothermic

animals that have little or no ability to regulate their body temperature, body temperatures fluctuate with the temperature of their environment, often referred to as 'cold-blooded'.

insectivore

An animal that eats mainly insects or spiders.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

molluscivore

eats mollusks, members of Phylum Mollusca

motile

having the capacity to move from one place to another.

natatorial

specialized for swimming

native range

the area in which the animal is naturally found, the region in which it is endemic.

oviparous

reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.

pet trade

the business of buying and selling animals for people to keep in their homes as pets.

riparian

Referring to something living or located adjacent to a waterbody (usually, but not always, a river or stream).

seasonal breeding

breeding is confined to a particular season

sedentary

remains in the same area

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

solitary

lives alone

tactile

uses touch to communicate

temperate

that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).

vibrations

movements of a hard surface that are produced by animals as signals to others

visual

uses sight to communicate

References

Buhlmann, K., T. Tuberville, W. Gibbons. 2008. Turtles of the Southeast. Athens, Georgia: University of Georgia.

Cagle, F. 1952. The Status of the Turtles Graptemys pulchara Baur and Graptemys barbouri Carr and Marchand, with Notes on Their natural History. Copeia, 4: 223-234.

Ernst, C., J. Lovich, R. Barbour. 1994. Turtles of the United States and Canada. Washington, DC: Smithsonian Institution Press.

Ferri, V. 2002. Turtles and Tortoises. Spain: Firefly Books.

Jacobson, E., C. Gardiner, S. Barten, D. Burr, A. Bourgeois. 1989. Flavobacterium meningosepticum infection of a Barbour's Map Turtle (Graptemys barbouri). Journal of Zoo and Wildlife Medicine, 20/4: 474-477.

Orenstein, R. 2001. Turtles, Tortoises and Terrapins Survivors in Armor. Canada: Firefly Books.

Valenzuela, N., V. Lance. 2004. Temperature Dependent Sex Determination in Vertebrates. Washington D.C: Smithsonian Institution Scholarly Press.

Wyneken, J., M. Godfrey, V. Bels. 2008. Biology of Turtles. United States: CRC Press.

van Dijk, P. 2012. "Graptemys barbouri" (On-line). IUCN Red List of Threatened Species. Accessed November 01, 2012 at http://www.iucnredlist.org/details/9496/0.

 
University of Michigan Museum of ZoologyNational Science Foundation

BioKIDS home  |  Questions?  |  Animal Diversity Web  |  Cybertracker Tools

Vasseur, G. 2012. "Graptemys barbouri" (On-line), Animal Diversity Web. Accessed April 18, 2014 at http://www.biokids.umich.edu/accounts/Graptemys_barbouri/

BioKIDS is sponsored in part by the Interagency Education Research Initiative. It is a partnership of the University of Michigan School of Education, University of Michigan Museum of Zoology, and the Detroit Public Schools. This material is based upon work supported by the National Science Foundation under Grant DRL-0628151.
Copyright © 2002-2014, The Regents of the University of Michigan. All rights reserved.

University of Michigan