Rhode Island is situated in New England and has an extensive coastline with sandy shores. Being situated on a flat coastal plain, the state is characterized by palustrine, lacustrine, and riverine wetlands, with the vast majority of them being red maple swamps and freshwater marshes. It experiences cold winters and warm summers, with a moderate amount of rainfall throughout the year.
Four species of aquatic and semi-aquatic snakes can be found in Rhode Island, each of which occupies a slightly different niche within the available habitats.
Rhode Island Water Snakes
1) Northern water snake (Nerodia sipedon)
- Native to the eastern US
- Family: Colubridae
- Order: Squamata
- Conservation status: Least concern
The northern watersnake can attain lengths of 61 – 107 cm (2 ft – 3 ft 6 in) and is a heavy-bodied reptile with keeled scales. The coloration of this species varies considerably, with individuals usually displaying a tan or gray body, with brown or red bands across the dorsum, and dark blotches on the sides. The underside may also display bands of color.
Nerodia sipedon is highly aquatic and can be found in many lakes, streams, and wetlands throughout Rhode Island. Populations appear to fluctuate in particular areas, as they will move to be at the points with the highest prey density. The diet of this species includes fish, amphibians, insects, crayfish, and the occasional small mammal.
Northern watersnakes are remarkably resilient to habitat alteration, and there are no conservation concerns about this species. These snakes give birth to live young, and reproduction is physically taxing for the female – her condition may decline considerably during the reproductive season.
2) Eastern garter snake (Thamnophis sirtalis sirtalis)
- Native to eastern North America
- Family: Colubridae
- Order: Squamata
- Conservation status: Least concern
The eastern garter snake usually grows to 46 – 66 cm (1 ft 6 in – 2 ft 2 in) in length, although records of 124 cm (4 ft 1 in) have been reported. This snake is slender, and dark in coloration, with three prominent yellow stripes running down the length of the body. However, not all individuals conform to this and may present grayish or reddish checkered patterning.
Thamnophis sirtalis sirtalis is semi-aquatic, occupying a variety of habitats including wetlands, forests, rocky hillsides, and urban areas. This species tends to stray further from water than the more aquatic snakes, and can often be seen basking on leaf litter or low branches. These snakes consume a diet of frogs, toads, fish, earthworms, and insects.
Populations of the eastern garter snake are stable, and few threats to this species are known. This snake is not venomous, however, it will strike if threatened, and its bite can cause an allergic reaction in some people.
3) Eastern ribbon snake (Thamnophis saurita)
- Native to the eastern US
- Family: Colubridae
- Order: Squamata
- Conservation status: Least concern
The eastern ribbon snake is very slender, with a typical length of 41 – 71 cm (1 ft 4 in – 2 ft 4 in). Similar to the eastern garter snake, individuals are dark in color, with three yellow lateral stripes – one running down each side, and one in the center of the back. The underside is pale cream in color. Despite its similarities, this species can be distinguished from the eastern garter snake by its slim build and its unpatterned lip scales.
In Rhode Island, Thamnophis saurita can be found on rocky hillsides, wetlands, and even in urban areas. Typically, individuals can be seen along the edges of rivers or streams, hiding amongst dense vegetation, where they feed predominantly on amphibians. Other prey items include fish, worms, and insects.
Eastern ribbon snakes are unlikely to bite, however, they will secrete a strongly scented musk if handled by a predator. Individuals will also undergo tail autotomy if faced with an extreme threat – the tail is not lost forever, however, and will eventually grow back.
4) Smooth green snake (Opheodrys vernalis)
- Native to the Nearctic region
- Family: Colubridae
- Order: Squamata
- Conservation status: Least concern
The smooth green snake is a small and slender species, reaching just 36 – 51 cm (1 ft 2 in – 1 ft 8 in) in length. This species is bright grassy green on the dorsum, while the underside is white or pale yellow. Juveniles can be distinguished from adults as they are dark blue-gray or olive-colored. The head is slightly wider than the neck.
Opheodrys vernalis can be found in coastal regions of Rhode Island, where it occupies dense grassy or shrubby areas. This species is insectivorous but will also consume arachnids and gastropod mollusks. Individuals have been found to prefer lepidoptera larvae over orthoptera larvae.
Although the overall conservation status of the smooth green snake is that of least concern, populations may be threatened by habitat loss or degradation. Protection and preservation of habitat is essential for the continued success of this species.
