Species Profile

Eastern Ribbonsnake Great Lakes population

Scientific Name: Thamnophis sauritus
Other/Previous Names: Northern Ribbonsnake (Great Lakes population)
Taxonomy Group: Reptiles
Range: Ontario, Quebec
Last COSEWIC Assessment: November 2012
Last COSEWIC Designation: Special Concern
SARA Status: Schedule 1, Special Concern

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Quick Links: | Taxonomy | Photo | Description | Distribution and Population | Habitat | Biology | Threats | Protection | Recovery Team | National Recovery Program | Documents

Image of Eastern Ribbonsnake

Eastern Ribbonsnake Photo 1
Eastern Ribbonsnake Photo 2



There are four subspecies of the Eastern Ribbonsnake, and only one, the Northern Ribbonsnake, is found in Canada.



The Eastern Ribbonsnake has three yellow longitudinal stripes on its back against a dark brown to black background. The chin and throat are pure white to fawn-coloured, and the belly is pale green, yellow, or white. The Eastern Ribbonsnake strongly resembles the more common and closely related Eastern Garter Snake in both colour and size. The most reliable way to distinguish between the two species is to see which scale rows have yellow stripes, but this is usually only possible with a captured specimen. In the field, one has to rely on comparisons; Ribbonsnakes are more slender and have longer tails than garter snakes. The tail accounts for at least one-third of the total length of an adult Eastern Ribbonsnake (46 to 86 cm). Both sexes have the same colour pattern, but females tend to be slightly larger and thicker-bodied than males. The young are miniature replicas of their parents.


Distribution and Population

The North American distribution of the Eastern Ribbonsnake extends from around the Great Lakes east of Lake Michigan to Florida. In Canada, there are two populations: the Great Lakes population of southern Ontario that is part of the main range of the species in the United States; and the disjunct Atlantic population in Nova Scotia. The distribution of the Great Lakes population roughly follows the southern edge of the Canadian Shield, with the most persistent sightings over time coming from the Georgian Bay region, particularly Bruce County. The snake has probably always been rare in Ontario. Although there have been no direct studies examining the size of this population, there is some evidence that it is becoming increasingly localized, even extirpated, in areas where it was once widespread.



The Eastern Ribbonsnake is semi-aquatic. It is most frequently found along the edges of shallow ponds, streams, marshes, swamps, or bogs bordered by dense vegetation that provides cover. Abundant exposure to sunlight is also required, and adjacent upland areas may be used for nesting.



Eastern Ribbonsnakes are diurnal (active during the day), gregarious, and very active, but timid and generally docile. They feed primarily on amphibians, particularly frogs. During winter (October to April), Eastern Ribbonsnakes hibernate in rock crevices, animal burrows, and even in ant mounds. Soon after they emerge in early spring, adults begin courtship, followed by mating. Females may move away from their normal habitats to drier areas to nest, as indicated by occasional observations of females and juveniles in upland areas. Live young are born in the early fall, usually in September. Litters are small, averaging 5 to 12 young, which are 16 to 24 cm long at birth. They take two to three years to reach maturity.



Threats to the Great Lakes population of the Eastern Ribbonsnake include loss and degradation of wetland and lakeshore habitats, declines in amphibian prey, persecution, collecting, accidental death on roads, and predation by pets and native wildlife.



Federal Protection

More information about SARA, including how it protects individual species, is available in the Species at Risk Act: A Guide.

The Eastern Ribbonsnake is not afforded any special legal protection in Ontario. It occurs, however, within several national parks, where it is protected by the Canada National Parks Act.

Provincial and Territorial Protection

To know if this species is protected by provincial or territorial laws, consult the provinces' and territories' websites.


Recovery Team

Thames River Recovery Team

  • Chris Harrington - Chair/Contact - Other
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PLEASE NOTE: Not all COSEWIC reports are currently available on the SARA Public Registry. Most of the reports not yet available are status reports for species assessed by COSEWIC prior to May 2002. Other COSEWIC reports not yet available may include those species assessed as Extinct, Data Deficient or Not at Risk. In the meantime, they are available on request from the COSEWIC Secretariat.

14 record(s) found.

COSEWIC Status Reports

  • COSEWIC Assessment and Status Report on the Eastern Ribbonsnake Thamnophis sauritus Atlantic population, Great Lakes population in Canada (2013)

    The Eastern Ribbonsnake is a small, slender semi-aquatic snake with a long tail. It can be identified by its black body with three, longitudinal yellow stripes, two lateral and one dorsal, running the length of the body. The side stripes occur on the 3rd and 4th scale rows. Below the stripe, the scales are caramel to rusty brown. There is a vertical white line in front of the eye.
  • COSEWIC assessment and status report on the eastern ribbonsnake Thamnophis sauritus in Canada (2002)

    In Canada, the Eastern Ribbonsnake (Thamnophis sauritus) is represented by a single subspecies, the Northern Ribbonsnake (Thamnophis sauritus septentrionalis). The Northern Ribbonsnake has three yellow longitudinal stripes on a dark dorsal background, and bears a strong resemblance to the closely related Common Gartersnake (Thamnophis sirtalis). The Northern Ribbonsnake can be distinguished from the Common Gartersnake by close examination of the stripes; those of the ribbonsnake fall on scale rows 3 and 4, whereas those of the gartersnake are on scale rows 2 and 3.

COSEWIC Assessments

  • COSEWIC Assessment - Eastern Ribbonsnake (2002)

    Eastern ribbonsnake - Atlantic population - Designated Threatened in May 2002. Assessment based on a new status report. Eastern ribbonsnake - Great Lakes population - Designated Special Concern in May 2002. Assessment based on a new status report.

Response Statements

  • Response Statement - Eastern Ribbonsnake, Great Lakes population (2013)

    The Great Lakes population is relatively widespread and appears to be locally abundant in a few sites. However, quantitative data are lacking on population size and trends, and most information is anecdotal and from protected areas.  Wetland and shoreline habitat loss and road development continue at an alarming rate within their range and present a significant threat to the species. Unless those losses are reversed the species is at risk of becoming Threatened. Road mortality and habitat loss are widespread and much of the species distribution occurs in pockets of habitat surrounded by agricultural land, roads and shoreline development.
  • Response Statements - Eastern Ribbonsnake (2004)

    A response statement is a communications document that identifies how the Minister of the Environment intends to respond to the assessment of a wildlife species by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC). The document provides a start to the listing and recovery process for those species identified as being at risk, and provides timelines for action to the extent possible.

Action Plans

  • Multi-species Action Plan for Bruce Peninsula National Park and Fathom Five National Marine Park of Canada (2016)

    Bruce Peninsula National Park (BPNP) and Fathom Five National Marine Park (FFNMP) lie at the tip of the Bruce Peninsula which separates Georgian Bay from Lake Huron. The peninsula is 90 km in length and its most prominent feature is the Niagara Escarpment which runs along the entire eastern edge. Within BPNP, the escarpment forms the Georgian Bay shoreline and is recognized as part of the core area of the Niagara Escarpment UNESCO World Biosphere Reserve.  BPNP was established by the federal government in 1987 to protect a representative example of the Great Lakes/St. Lawrence Lowlands natural region. Because of the fragmented nature of the park properties, many of the stresses on the park’s ecosystem originate from outside its boundaries. For this reason, First Nations, local residents, non-governmental organizations, and other groups and land users play an important role in managing, restoring, and protecting the northern Bruce ecosystem. 
  • Multi-species Action Plan for Georgian Bay Islands National Park of Canada (2016)

    Georgian Bay Islands National Park (GBINP) is located in southeastern Georgian Bay in the heart of Ontario’s cottage country. Georgian Bay is home to the world’s largest freshwater archipelago, the 30,000 Islands, and the park acts as a southern gateway into this area. Comprising 63 dispersed islands and shoals the total area of the park is 14 km2 from the Centennial Group in the south to McQuade Island 50 kilometres northward. Situated just 150 km from the Greater Toronto Area (GTA), GBINP is within a half-day’s drive for millions of Canadians. Created in 1929 it is Canada’s smallest national park straddling two natural regions and forms a core protected area of the Georgian Bay Biosphere Reserve. The park lies on the edge of the Canadian Shield and is home to both northern and southern plants and animals. The islands are renowned for the variety of reptiles and amphibians they support. The park also has significant cultural value, having been occupied continuously for over 5,500 years. Maintenance and restoration of ecological integrity is the first priority of national parks (Canada National Parks Act s.8(2)). Species at risk, their residences, and their habitat are therefore protected by existing national park regulations and management regimes. In addition, the Species at Risk Act (SARA) prohibitions protecting individuals and residences apply automatically when a species is listed, and all critical habitat in national parks and national historic sites must be legally protected within 180 days of being identified.
  • Multi-species Action Plan for Thousand Islands National Park of Canada (2016)

    The Multi-species Action Plan for Thousand Islands National Park of Canada is a Species At Risk Act action plan (SARA s.47) for four species: American Water-willow (Justicia americana), Butternut (Juglans cinerea), Deerberry (Vaccinium stamineum), and Pugnose Shiner (Notropis anogenus). The plan also outlines measures to monitor and manage 30 other species of conservation concern that regularly occur in the park. This plan applies only to lands and waters occurring within the boundaries of Thousand Islands National Park of Canada.

Management Plans


  • Order Acknowledging Receipt of the Assessments Done Pursuant to Subsection 23(1) of the Species at Risk Act (2004)

    This Order acknowledges receipt by the Governor in Council of the assessments of the status of wildlife species done pursuant to subsection 23(1) of the Species at Risk Act (SARA) by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC). The purpose of SARA is to prevent wildlife species from being extirpated or becoming extinct, to provide for the recovery of wildlife species that are extirpated, endangered or threatened as a result of human activity and to manage species of special concern to prevent them from becoming endangered or threatened.
  • Order Amending Schedules 1 to 3 to the Species at Risk Act (2005)

    Schedule 1, the List of Wildlife Species at Risk of the Species at Risk Act (SARA), is amended by Order of the Governor in Council (GIC), on the recommendation of the Minister of the Environment, by the addition of 73 species. This Order is based on scientific assessments by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) and follows consultations with provincial and territorial governments, Aboriginal peoples, stakeholders and the public, and analysis of costs and benefits to Canadians.

COSEWIC Annual Reports

  • COSEWIC Annual Report – 2012-2013 (2013)

    Under Canada’s Species at Risk Act (SARA), the foremost function of COSEWIC is to “assess the status of each wildlife species considered by COSEWIC to be at risk and, as part of the assessment, identify existing and potential threats to the species”. COSEWIC held two Wildlife Species Assessment Meetings in this reporting year (October, 2012 to September 2013) from November 25 to November 30, 2012 and from April 28 to May 3, 2013. During the current reporting period, COSEWIC assessed the status or reviewed the classification of 73 wildlife species. The wildlife species assessment results for the 2012-2013 reporting period include the following: Extinct: 0 Extirpated: 2 Endangered: 28 Threatened: 19 Special Concern: 19 Data Deficient: 4 Not at Risk: 1 Total: 73 Of the 73 wildlife species examined, COSEWIC reviewed the classification of 50 species that had been previously assessed. The review of classification for 26 of those species resulted in a confirmation of the same status as the previous assessment.

Consultation Documents

  • Consultation on Amending the List of Species Under the Species At Risk Act: March 2004 (2004)

    The Government of Canada proclaimed the Species at Risk Act (SARA) on June 5, 2003 as part of its strategy for the protection of wildlife species at risk. Attached to the Act is Schedule 1, the list of the species that receive protection under SARA, hereinafter referred to as the 'SARA list'. Canadians are invited to comment on whether all or some of the species included in this document should be added to the SARA list.

Recovery Document Posting Plans

  • Environment and Climate Change Canada's Three-Year Recovery Document Posting Plan (2016)

    Environment and Climate Change Canada’s Three-Year Recovery Document Posting Plan identifies the species for which recovery documents will be posted each fiscal year starting in 2014-2015. Posting this three year plan on the Species at Risk Public Registry is intended to provide transparency to partners, stakeholders, and the public about Environment and Climate Change Canada’s plan to develop and post these proposed recovery strategies and management plans. However, both the number of documents and the particular species that are posted in a given year may change slightly due to a variety of circumstances. Last update March 31, 2017