Get to know some of the species at risk in the Lac Deschênes IBA with the Species Spotlight, aka “Sp-Spot”. Today meet the: Eastern Musk Turtle
Scientific Name: Sternotherus odoratus
SARA Status: Threatened; Ontario: Threatened; Quebec: Threatened
Taxonomic Group: Reptile
Size: Typically between 5.1 and 11.5cm long, although the largest individual on record was 13.7 cm long.
The musk turtle is one of the smallest species of turtles in North-America. It has two light yellow stripes on each side of its head, and barbels on the chin and the throat. The carapace (the upper shell) of the musk turtle is smooth and its color can vary amongst individuals between olive green, brown, and almost black. The plastron (the shell breastplate) of the musk turtle is proportionally smaller than the plastron of other turtle species, as it has been reduced to allow for greater leg movements.
Musk turtles hibernate during the winter. They must avoid freezing so they burrow in the muddy bottom of lakes, rivers, ponds or marshes. In the spring, they are most abundant in warm shallow bays where the water is heated by the sun. They can be seen basking on sunny days near the surface of still waters, amid the vegetation. As the season progresses, the water temperature increases and the musk turtles disperse to deeper waters. During the active season, musk turtles crawl along muddy bottoms in search of food. They are omnivorous and eat mainly mollusks such as snails and zebra mussels, and insect larvae such as caddisfly larvae. They are able to remain underwater for extended periods of time since, in addition to having lungs and being air-breathers, they can also exchange gases via their cloaca. In fact, the great majority of their time is spent submerged in the water allowing algae to grow on their carapace.
Musk turtles breed underwater. Females lay eggs in shallow excavations that they dig themselves, or that they find near the edge of the water. Direct sunlight is needed on the nest during incubation as the female’s work is done as soon as the eggs are laid. The hatchlings emerge 2-3 months later.
Where Else Can You See This Species?
Musk turtles are only found on the eastern side of the North-American continent from the edge of the Canadian Shield in Ontario and Quebec south to Texas, and as far west as Wisconsin. These turtles are difficult to detect as they rarely leave the water and so data is limited on their distribution. Across their range, musk turtle population density seems to be low because the number of sightings is low, however, some local populations can reach very high densities.
Did you know?
• The Musk Turtle is also called the “Stinkpot” due to the two glands under the edge of the carapace which release a very foul smelling liquid. Releasing this yellowish musk serves as an anti-predator mechanism.
• This turtle may spend most of its time underwater, but many sources portray the musk turtle as an avid tee climber. However musk turtles are rarely seen on land or in trees. Although the reduced size of their plastron allows for greater mobility, they dehydrate out of water much faster than other turtles.
Check back every week to read about a different species at risk that can be found in Lac Deschênes.
You can report sightings of this and other rare species to the Canadian Wildlife Service at (819) 997-2800 or on the MNR Natural Heritage Information Centre website. A photo and a location are very helpful!
We would like to thank our guest blogger Julie Châteauvert for this post. Julie is a biologist from Gatineau Québec who is interested in herpetology and natural history.