Yellow-blotched map turtle  (Graptemys flavimaculata)

The yellow-blotched map turtle is classified as Vulnerable (VU) on the IUCN Red List (1)

The yellow-blotched map turtle (Graptemys flavimaculata) is sometimes referred to as the yellow-blotched sawback turtle due to bizarre saw-like projections on its back. These projections stem from the centre of the turtle’s shell, mimicking the spine (2) (3).

The shell of this species is olive-brown, with yellow blotches covering the majority of the surface. Around the yellow blotches are thick yellow margins, sometimes called semicircles because of their shape. Along the seams of the shell are light cream and black colour patterns. These patterns are important as they are used to determine the age of the turtle, with the patterns fading as the turtles ages (2).

The male yellow-blotched map turtle has a long, thick tail and an elongated foreclaw, which it uses during courtship (2) (3). The yellow-blotched map turtle has a small head, although the female’s is broader and larger than the male’s (2). The skin is olive with yellow stripes. However, in some individuals the yellow is so dominant it appears that the map turtle is yellow with olive stripes (2) (3).

The yellow-blotched map turtle is endemic to Missipippi in the United States. It is found in the Pascagoula River system, including the Leaf, Escatawpa and Chickasawhay rivers (1).

The yellow-blotched map turtle lives primarily on sandbars within sand or clay bottomed streams and rivers, formed by moderate currents. It has also been found along banks, either with limestone ledges or rocky bottoms (1) (2).

The diet of the yellow-blotched map turtle mainly consists of snails and insects. The male and juvenile predominantly eat insects, while the female mainly consumes molluscs. The female will occasionally take insects as well (2).

The male yellow-blotched map turtle reaches maturity at three to four years old, whereas the female doesn’t reach maturity until eight to ten years of age (1). During courtship, the male yellow-blotched map turtle will extend its neck and move towards the female. The female will show interest by extending its neck towards the male in reply, after which the male will stretch its forelimbs and stroke the side of the female’s head with its claw (3).  The reproductive season lasts between 80 and 87 days (2).

The female yellow-blotched map turtle is very sensitive to the presence of humans during nesting. Disturbances to the female during efforts to nest can delay the female for hours, sometimes resulting in a failed nesting attempt. Clutch size normally ranges from three to nine eggs (2). Sometimes the female may produce more then one clutch per year, though this is quite rare. Often, the female will skip a year or two between producing eggs (1). The eggs and hatchlings of the yellow-blotched map turtle are preyed on by fish crows (Corvus ossifragus), king snakes (Lampropeltis sp.), fire ants (Solenopsis sp.), and grey foxes (Urocyon cinereoargenteus) (2).

The majority of the day is spent basking and the yellow-blotched map turtle is quite difficult to approach, being wary of humans (2) (4).

The yellow-blotched map turtle is threatened by the pet trade, and by rising river water levels causing sandbars and nests to flood (2). When basking, this species is sometimes used as target practice by hunters, and many are killed (3) (5) (6). Nest predation by natural predators is extremely high, with up to 90 percent of young predated. Human disturbance at preferred nesting sites can drastically reduce the reproductive success of this species (1).

The loss and alteration of habitat is a serious threat to this species. The degradation of water quality due to pollution and the accumulation of toxic materials is also a major problem, as it is known to affect the major prey species that form the yellow-blotched map turtle’s diet (5).

The yellow-blotched map turtle was listed as federally threatened under the Endangered Species Act in 1991 (1). It is also protected by the state of Mississippi, however legislation has been difficult to enforce. The yellow-blotched map turtle lives within the Pascagoula River Wildlife Management Area. In an effort to protect more river habitat there are gates and signs within the management area to stop vehicles entering potential nesting areas of the yellow-blotched map turtle (6).

It has been recommended that the yellow-blotched map turtle is protected from floods, the pet trade and increasing pollution in the Pascagoula River (3) (5) (6).

For more information on freshwater turtle conservation:

• IUCN/SSC Tortoise and Freshwater Turtle Specialist Group:
  http://www.iucn-tftsg.org/
• Conservation International - Freshwater Turtles:
  http://www.conservation.org/learn/biodiversity/species/profiles/turtles/Pages/freshwater_turtles.aspx