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Canadian Herpetological Society Société d'Herpétologie du Canada |
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Eastern Musk Turtle
Sternotherus odoratus
Family: Kinosternidae
Other / Previous Names: Stinkpot
COSEWIC status:- Special Concern
- Special Concern
- Least Concern
Description
The Eastern Musk Turtle has a narrow, domed carapace (upper shell) that is light brown to black with black flecking and is often partially covered by algae. The plastron (lower shell) is yellowish to brown. The plastron is relatively small and offers little protection to the legs; however, a hinge allows the front of the plastron to be pulled partially closed. The head and limbs are dark brown, grey or black, and adults usually have two yellowish stripes on each side of the head that extend backward from the snout above and below the eye. There are two barbels (fleshy projections) on the chin and throat. This small turtle can reach a maximum carapace length of 15 cm, though most adults are smaller than this. Hatchlings have a carapace length of 1.7–2.5 cm and generally resemble adults in colour and pattern, but have three weak keels on the carapace.
Similar Species
Painted Turtles have red and yellow stripes on the head and legs, red on the sides and undersides of the carapace and a flat, broad carapace. Banding’s Turtles have a distinct yellow chin and throat. Spotted Turtles have large yellow spots on the carapace. Snapping Turtles, which get significantly larger than musk turtles, have prominent ridges on the tail and a carapace that is flat and broad with serrations along the rear margin.
Distribution
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The Canadian range of the Eastern Musk Turtle is restricted to southern Ontario and a few locations in southwestern Quebec. The range of this species extends throughout much of the eastern United States as far south as Florida and Texas.
Habitat
Eastern Musk Turtles inhabit open-water wetlands, ponds, lakes and rivers with little or no current and a soft bottom. Within larger bodies of water, this species is typically found in shallow areas with abundant vegetation, such as bays or coastal marshes. Eastern Musk Turtles overwinter at the bottom of water bodies, often buried in the soft bottom. Females nest in open-canopy habitats along shorelines, on muskrat lodges or in rotten logs and stumps, and nest sites are usually within a few metres of water.
Biology
In Canada, Eastern Musk Turtles are dormant during the winter and are typically active from April until early October. Females nest from late May to early July and nests typically contain 2–5 elliptical eggs. Hatchlings emerge in the fall and their sex is determined by the incubation temperature of the nest; warmer incubation temperatures produce females, whereas cooler temperatures produce both males and females. Eastern Musk Turtles mature in 4–8 years, which is much earlier than most other Canadian turtles. Individuals may live more than 25 years in the wild. Individuals typically forage while walking along the bottom of aquatic habitats, and they eat a wide variety of prey, including small invertebrates, algae, carrion, fish eggs, minnows, crustaceans and tadpoles. Eastern Musk Turtles bask under floating vegetation at the surface of the water and are rarely seen basking on rocks or logs. This species emits a foul-smelling secretion from scent glands on its underside when it is threatened.
Threats
Wetland destruction and shoreline alteration have caused the Eastern Musk Turtle to decline or disappear from many areas in southwestern Ontario, and ongoing habitat loss continues to threaten this species throughout its Canadian range. This species is not affected by road mortality as much as other Canadian freshwater turtles because they rarely travel far from water. However, the tendency of these turtles to bask at the surface of the water makes them vulnerable to propeller strikes, which may result in significant mortality rates in areas with high motorboat traffic. Since this species is regularly captured in commercial fishing traps, drowning in these traps is likely the most significant source of mortality in some areas. Climate change poses a potentially serious future threat to Canadian turtles.