Eastern Musk Turtle

(Sternotherus odoratus)

Status: Special Concern Ontario; Threatened Federally

Table of Contents:

Species Identification
Diet
Habitat and Range
Biology and Behaviour
Similar Species
Threats/Reasons for Being Endangered
Conservation and Recovery Strategies
How You Can Help

Species Identification:

The Eastern Musk Turtle is very small in size, rarely exceeding 13 cm in length. The carapace (top shell) is narrow and domed-shaped, and the colour ranges from grey to brown/black. The carapace sometimes has dark streaks or spots and is often covered in algae or mud. Their plastron (bottom shell) is smaller than the carapace and cross-shaped. The colour ranges from brown to yellow/cream. The Eastern Musk Turtle can be identified by their pointed snout with two yellow or white stripes extending from the nose across each side. They have a large head size in relation to their carapace. Eastern Musk Turtles are also affectionately referred to as “Stinkpots” because of the musk they emit, which is most likely to deter predators.

Diet:

Eastern Musk Turtles are bottom-feeding omnivores with a preference for meat and a strong enough bite to break open the shells of small snails and mussels. They also eat aquatic insects, carrion, earthworms, leeches, tadpoles, crustaceans, crayfish, insect larvae, algae, and aquatic plants. These little stinkpots often remain under the water for long periods of time to forage on the bottom of wetlands, lakes, ponds, or rivers. They prefer to forage and rest in places with lots of vegetation for hiding.

Map taken from Government of Canada: https://www.sararegistry.gc.ca/virtual_sara/files/plans/rs_eastern_musk_turtle_e_proposed.pdf

Habitat and Range:

Eastern Musk Turtles are found in Eastern North America, spanning from Florida up to Ontario and Quebec, and west to Wisconsin and central Texas. Approximately 5% of their global range lies in Canada, or more specifically southern Ontario, the southeastern edge of northeastern Ontario, and the southwestern edge of Quebec. The Land Between has a very high proportion of Canadian populations of the Stinkpot.

Stinkpots are the most active at dawn and dusk. They are a highly aquatic species that prefer well-vegetated areas near the shore of shallow waterways, including rivers, shallow lakes, marshes, bays, streams/rivers, ponds, canals, and swamps- with soft bottoms and slow currents. They rarely go on land except to nest or to access adjacent wetlands, since they are much slower and less agile. Unlike other turtle species, they will not usually bask out of water due to a high risk of drying out or predation, so they typically bask near the surface of the water, under the cover of floating vegetation and debris.

The Eastern Musk Turtle may travel long distances in order to travel from feeding, nesting, or hibernating sites, usually in late April and early May, and then again in late September and early October. Movement on land usually occurs at night, and usually using aquatic corridors, which is why Stinkpots are so difficult to locate. Their home range distances have been reported to be anywhere between 6.2 and 155 hectares.

Biology and Behaviour:

Active season for the Eastern Musk Turtle is from April to early October. They can be seen basking in shallow water or crawling along the bottom of shallow water. Stinkpots can breathe using both air and water, which allows them to stay underwater for long periods of time without the need to resurface. They will not often bask out of water, but near the surface of water under the cover of lily pads or other floating vegetation and debris. Stinkpots are adept at both swimming and walking along the bottom of a body of water, especially when foraging.

During the nesting season, which is generally mid-May to early July, female Stinkpots will dig shallow nests in decaying plant matter, rotting wood, sand, sparse shoreline grasses, sawdust piles, or in the walls of muskrat and beaver lodges. Most nests are shallow, with a maximum depth of about 10 cm. Nest sites are usually very close to shore, and they are generally laid at night. Eastern Musk Turtle females do not always dig their nest- they can also just scrape away decaying plant matter, rotting wood or other debris and cover the eggs back up. She will lay 1-9 eggs either once or twice a year. Incubation usually lasts for 65 to 86 days, and hatchlings will emerge in August and September

Once the weather starts to get cold, Stinkpots will travel to their hibernation sites, which are located at the bottom of shallow water, or in beaver and muskrat lodges.

Similar Species:

Eastern Musk Turtles are often mistaken for juvenile Snapping Turtles because of their defensive behaviour when handled, and they have reduced plastrons (bottom shell) similar to a Snapper. To distinguish between this species and juvenile Snappers remember Stinkpots have the distinct white/yellow stripes along each side of their face, and Snapping Turtles have long tails with triangular upright scales
The Eastern Musk Turtle’s domed shell is often mistaken for a juvenile Blanding’s Turtle, but Stinkpots lack the yellow chin and yellow-flecked shell

Threats/ Reasons for being at Risk:

In both Ontario and Quebec where Stinkpots have been historically reported, 28% of them have not reported sightings since 1986. In Ontario, population declines have been observed, and are inferred from the following known threats:

1. Habitat destruction and degradation: Development of shoreline and subsequent loss of vegetation is detrimental for Stinkpots, since they rely a great deal on a high amount of vegetation in the shoreline and shallow water. This area is where they spend most of their time and where they carry out all their basking and foraging activities. As people move northward to escape the city, either permanently or for vacationing, more and more of the shoreline in Ontario is being urbanized. Houses on the waterfront are generally cleared of natural vegetation to allow for an unobstructed view of the water.

2. Boating mortality: Since Stinkpots generally do not venture on land, boat collisions and propeller damage are major sources of mortality for these turtles. They are a highly aquatic species and spend a lot of time basking at the surface of the water under vegetation that often gets caught up or shredded by boat propellers.

3. Fishing bycatch: Passive fishing techniques catch a lot of turtles unintentionally and nets can go days without being checked, resulting in turtle mortalities. Stinkpots are also often caught by anglers’ baited hooks and can die from the damage or sustain serious injuries.

4. Water control structures: This species travels between wetlands almost exclusively using aquatic corridors - if dams and locks prevent movement between water bodies, this creates fragmentation for Stinkpots and populations can become isolated from one another. Drastic changes in water levels can also flood and drown nests along the shore, as well as change habitat along the shoreline, which is exacerbated by climate change.

Conservation and recovery strategies:

Ideal conservation strategies would include maintaining aquatic connectivity of water bodies, protecting and restoring habitat-particularly shorelines, restoration projects and land acquisition. The government should also focus on regulating shoreline development and reducing boating speed limits or access to wetland areas.

Since the Eastern Musk Turtle is only listed as Special Concern in Canada, no direct efforts are being done by the Government. However, environmental organizations across Canada just like The Land Between have stepped up to help. The Land Between has workshops dedicated to helping landowners redesign their shorelines to bring them back to their natural state. This will not only help the Stinkpot, but also many other lake and wetland species. Environmental organizations are also trying to spread the word about the Eastern Musk Turtle, in order to encourage public awareness and participation to rehabilitate and keep their habitats safe.

How can you help?

Keep shorelines on your property natural - this is critical for Stinkpots, as habitat loss and degradation is their current top threat. Sign up for a Design-Your-Own Shoreline Garden Workshop hosted by The Land Between.
Reduce the speed of your boat near the shore and among aquatic vegetation. Avoid driving through thick vegetation or wetland areas whenever possible.
Avoid fishing in Stinkpot habitats (i.e. near heavily vegetated shorelines), especially with baited and barbed hooks. If you happen to hook a Stinkpot by accident, do not just cut the line. Instead, carefully remove the turtle from the water- do not hold the turtle up by the hook and line. If the hook is too difficult to safely remove, snip the line with the hook still in and call Ontario Turtle Conservation Centre or Turtle Guardians/The Land Between to have the hook safely removed by an expert.
Report sightings of Stinkpots on The Land Between website or iNaturalist.
Talk to your local government about halting shoreline development or keeping shorelines natural.

Additional Resources:

Ontario Nature Eastern Musk Turtle page
Ontario Turtle Conservation Centre
Carolinian Canada Coalition pamphlet
Connecticut Department of Environmental Protection pamphlet

Sources:

Ernst, C. (1986). Ecology of the Turtle, Sternotherus odoratus, in Southeastern Pennsylvania. Journal of Herpetology, 20(3), 341-352.

COSEWIC. 2012. Eastern musk turtle (Sternotherus odoratus): COSEWIC assessment and status report. Committee on the Status of Endangered Wildlife in Canada. Ottawa. xiii + 68 pp. https://www.canada.ca/en/environment-climate-change/services/species-risk-public-registry/cosewic-assessments-status-reports/eastern-musk-turtle-sternotherus-odoratus.html

Environment Canada. 2016. Recovery Strategy for the Eastern Musk Turtle (Sternotherus odoratus) in Canada [Proposed]. Species at Risk Act Recovery Strategy Series. Environment Canada, Ottawa. viii + 58 pp. https://www.sararegistry.gc.ca/virtual_sara/files/plans/rs_eastern_musk_turtle_e_proposed.pdf