Northern Ribbonsnake

(Thamnophis sauritus septentrionalis)

Status: Special concern (COSEWIC 2012, ESA 2013)

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 Northern Ribbonsnake is a long (46-86 cm), thin-bodied black snake with three yellow stripes running down their back and along their sides. A white chin, white-yellow belly, and white crescent moon shaped scale in front of both eyes helps differentiate this snake from the Eastern Gartersnake. Both sexes look identical, but females are typically larger than males.

Diet:

Eastern Ribbonsnakes mainly feed on amphibians but will sometimes prey upon small fish and invertebrates. Frogs make up the majority of their diet. While Eastern Ribbonsnakes are diurnal, they have been known to nocturnally hunt during the frogs active breeding season.

Map taken from: https://www.tn.gov/twra/wildlife/reptiles/snakes/eastern-ribbonsnake.html

Habitat and Range:

The Land Between represents the majority of Eastern Ribbonsnake’s range due to habitat loss and degradation in southern Ontario, and the limited active season length north of Killarney Provincial Park. Eastern Ribbonsnake populations are in pockets around the Great Lakes, and throughout southern Ontario, Michigan, Indiana, Illinois, Ohio, Pennsylvania, New York, Vermont, New Hampshire, and Maine. There are also small, isolated populations in southern Nova Scotia and southern Wisconsin.

Eastern Ribbonsnakes are a semi-aquatic species and are usually found near permanent water sources that have access to dry land. Wetlands are their preferred habitat due to the abundance of prey, accessible water sources, and access to dry land for thermoregulation. They also tend to reside near shallower water bodies as opposed to larger deeper lakes.

Biology and Behaviour:

Eastern Ribbonsnakes come out of hibernation in early spring and head to their breeding grounds. They will mate in the spring and the female will give birth to 5-12 live young in late July or August. Juvenile Eastern Ribbonsnakes leave the nest immediately and are able to thrive on their own. They eat small invertebrates until they are large enough to successfully hunt amphibians.

They are most active from April to October, often basking on hummocks (peat mounds), logs, bushes, and rocks to keep warm. They are good swimmers and will head to shallow water to cool down or hide from predators. When threatened, the Eastern Ribbonsnake produces a foul smelling musk that is meant to deter predators. Predators include raccoons, mustelids, herons, birds of prey, domestic pets, and predatory fish.

Eastern Ribbonsnakes hibernate underground and have been known to use a variety of different habitats such as ground fissures, rodent burrows, building foundations and under cement paths. They usually hibernate close to water to maintain temperature and prevent dehydration.

Photo by mbarrison: https://flic.kr/p/nwEE8M

Similar Species:

The Eastern Gartersnake is easily confused with the Eastern Ribbonsnake since they both are black with yellow lines, and are the same size as the juvenile Eastern Ribbonsnake. They can be differentiated by the Eastern Ribbonsnake’s white scale in front of the eye, and the lateral lines on the 3rd and 4th scale row as opposed to the lines on the Gartersnake which occur on the 2nd and 3rd scale row.

Threats/ Reasons for being at Risk:

1. Habitat loss and degradation: Like many Species at Risk, habitat loss and degradation is a major threat. While Eastern Ribbonsnakes prefer wetland habitats, many of these have been drained and filled for agriculture, or developed as cities expand and people acquire cottages. The Land Between houses the majority of Eastern Ribbonsnakes in Ontario, but they are now at risk as people move northward to escape the city.

2. Road mortality: Road development goes hand in hand with urban development as populations expand. Snakes are at risk when they attempt to cross roads or if they think they are suitable basking areas. Many drivers do not watch for snakes on roads, or they will purposely hit them out of fear or anger.

3. Persecution: All snake species are commonly persecuted by people due to fear. Most snakes in Ontario are generally harmless, but people fear their bite and their quick movements. Snakes are often found in people’s backyards and gardens, and while they are beneficial since they eat many backyard pests, they often frighten people. There is a great deal of misinformation when it comes to snake species, and most people would rather get rid of them than learn more about them.

4. Reduced prey abundance: The Eastern Ribbonsnake’s main source of prey are amphibians, but there has been a dramatic decrease in amphibian species over the past few years. While the reason is relatively unknown, it is suspected that amphibians are subjected to habitat loss, pollution, climate change and disease.

Conservation and recovery strategies:

Habitat loss and degradation: The Haliburton Highlands Land Trust’s (HHLT) “Wetland Reconnaissance and Community Mobilization for Recovery of Species at Risk” project identified 2,596 hectares of wetland as important habitat that will be used for future conservation planning and property acquisition. Five workshops were held highlighting reptiles at risk- including the Eastern Ribbonsnake, through the distribution of educational resources. In 2010, a new observation of an Eastern Ribbonsnake was reported and verified as a result of the species at risk media campaign.

More than 9,600 hectares of wetland has been secured and over 30,000 hectares have been rehabilitated through the multi-partner approach of the Eastern Habitat Joint Venture of the North American Waterfowl Management Plan, Great Lakes Wetlands Conservation Action Plan, and Ecological Gifts Program. The Eastern Ribbonsnake and other species occurring in wetland habitats benefit greatly from ongoing wetland conservation programs and partnerships.

Photo by Andrew Hoffman: https://flic.kr/p/CHGYm

Persecution: Sciensational Sssnakes!! and Scales Nature Park presented sessions about Species at Risk reptiles throughout various regions of Ontario, especially southern Ontario, where road mortality is a high threat. Programs were conducted at schools, community centers, public libraries, scouting groups, parks, fairs, and other public venues. In many presentations, live Eastern Ribbonsnakes were on display for the public to view and learn about. Analysis of pre- and post- program surveys showed statistically significant increases in participants' knowledge (60% increase) and attitude (13% increase) scores regarding snakes. The long-term result of this project will be increased awareness of, and interest in, issues relating to reptile conservation, decreased persecution, and increased support for other conservation activities.

Photo by Melissa McMasters: https://flic.kr/p/vbJY4n

Road Mortality: The Ontario Road Ecology Group (OREG) at the Toronto Zoo applied a Geographic Information System (GIS) model that predicts and prioritizes where roads act as wildlife mortality sinks and barriers to habitat connectivity in various municipal, provincial and federal road projects. OREG has investigated the effects of roadside habitat restoration on wildlife road mortality trends and is working with municipal partners (including planners and Conservation Authorities) to reduce the occurrence of wildlife-vehicle collisions. In addition, OREG has initiated local wildlife-road interaction monitoring projects involving citizen scientists and workshops to improve input to environmental assessments to promote and improve species at risk recovery efforts.

The Long Point Causeway Improvement Project is intended to reduce road mortality of reptiles and restore aquatic connectivity between the Big Creek Marsh and Long Point Bay, near Port Rowan, Ontario. Activities have included the installation of about 5,000 metres of barrier fencing along the roadway, the construction of three ecopassages allowing animals to pass under the road, the installation of artificial nest mounds for turtles and an on-going public education and outreach program to highlight the dangers roads pose to reptile species and ways that those dangers can be mitigated.

Nature Conservancy of Canada- During 2012 and 2013, road mortality surveys were conducted in the Bruce Peninsula region. A total of 22 Eastern Ribbonsnakes were found, 18 of which were dead on the road. This information will then be used to implement mitigation efforts in the identified hotspot areas.

Parks Canada: National Parks that have Eastern Ribbonsnakes, such as Thousand Islands, Point Pelee, Georgian Bay Islands, and the Bruce Peninsula, regularly present outreach and in-park education programs for Species at Risk, which have been going on for decades.

How can you help?

Encourage landowners to rehabilitate shoreline habitat and preserve any wetland habitat whether it be significant or not to maintain the biodiversity that these snakes require to survive.
Educate your friends, family, and neighbours about Ontario snakes and the benefits and myths that are associated with them.
Landowners should look into safe chemical and pollutant use around wetlands.
Help a snake across the road in the direction they are travelling!
Support organizations dedicated to helping snakes and other wildlife.

Additional Resources:

Ontario Nature’s Eastern Ribbonsnake page
Canadian Herpetological Society page
Nature Canada’s Species Spotlight: Eastern Ribbonsnake

Sources:

Government of Ontario. 2014. Eastern Ribbonsnake. Retrieved from: https://www.ontario.ca/page/eastern-ribbonsnake

Environment Canada. 2014. Management Plan for the Eastern Ribbonsnake (Thamnophis sauritus), Great Lakes population, in Canada [Proposed]. Species at Risk Act Management Plan Series. Environment Canada, Ottawa. iv + 23 pp