1. Prairie Rattlesnake (Crotalus viridis)
We’ll kick off the list with the only venomous snake in Montana – the prairie rattlesnake. Also known as the western rattlesnake, this snake lives everywhere in Montana, with the exception of the northwest corner of the state. It typically prefers to live in dry, rocky regions, as well as regions with tall grass, mixed coniferous forests, and along riverbanks. Prairie rattlesnakes are 15 to 60 inches long and have heavy bodies with triangular-shaped heads. They are usually tan, brown, or olive green with dark brown or black blotched markings. They also have keeled dorsal scales and a white or yellow belly. Prairie rattlesnakes are highly venomous, and their venom contains neurotoxic and hemotoxic properties. However, they are shy and prefer to flee from threats rather than stand their ground and attack. Even if you do come across a prairie rattlesnake, it will rattle its tail a lot in warning or coil its body, then raise its head up off the ground first in a defensive posture before it actually strikes. When it comes to prey, prairie rattlesnakes are ambush predators and feed mainly on small mammals and birds.
2. Eastern Racer (Coluber constrictor)
Another black snake in Montana is the eastern racer which is usually a glossy black or grey with a white or yellow belly. Eastern racers are 20 to 75 inches long and have slender bodies. They are widespread across Montana and live in forests and grasslands. They are quick, active snakes and have excellent eyesight. One of the most common postures that they adopt is to paise with their heads raised up off the ground as they look for prey. Despite their scientific name, eastern racers are not truly constrictors. Instead of coiling their body around their prey until it dies, they simply subdue it before swallowing it alive. Eastern racers prey on small mammals, birds, reptiles, amphibians, and other snakes. Although they are not venomous snakes, you should never attempt to handle an eastern racer as they are aggressive and will bite if threatened. They also release a foul-smelling musk.
3. Bullsnake (Pituophis catenifer sayi)
There are six subspecies of the gopher snake and bullsnakes are the subspecies which are common in Montana. Bullsnakes are the largest snakes in Montana and can reach lengths of up to 72 inches. They have yellowish bodies with large dark brown or black blotches. Due to their appearance, they can sometimes be mistaken for the prairie rattlesnake which can lead to them being mistakenly killed in some cases. Bullsnakes are constrictors but sometimes mimic rattlesnakes by vibrating their tail in the leaf litter, which is another reason they are easily mistaken. Bullsnakes prefer to live in dry regions such as prairies and pastures. They are widespread across Montana but are most prolific in areas where there are high rodent populations. However, they don’t prey solely on rodents as they are well known for their ability to climb trees and raid bird nests.
4. Common Garter Snake (Thamnophis sirtalis)
The next few black snakes in Montana are garter snakes. The first is the common garter snake which is typically 16 to 42 inches long. These snakes are brown, black, or green with yellow or cream stripes – one down their back and one along either side. They also occasionally have small red spots between the stripes. Common garter snakes are found across the entire state. They live in forests and grasslands near permanent sources of water. Although common garter snakes are not considered to be dangerous to humans, they are mildly venomous to their prey. Common garter snakes often prey on amphibians and are immune to the poison produced by toads.
5. Western Terrestrial Garter Snake (Thamnophis elegans)
The next garter snake is the western terrestrial garter snake which is distinguishable from the common garter snake by its lighter color. They are typically greyish-green but have black spots between their yellow dorsal and lateral stripes. However, sometimes these snakes can have entirely dark or black coloring. Western terrestrial garter snakes can be found all over Montana, with the exception of the northeast corner. They live in virtually all habitats – including forests, prairies, and pastures. Western terrestrial garter snakes often kill their prey by constriction, but they also contain a mild venom in their saliva. Despite this, they are not considered to be truly venomous and are not dangerous to humans. Bites from these snakes typically cause only localized swelling and itching.
6. Plains Garter Snake (Thamnophis radix)
The plains garter snake has a similar appearance to the previous two garter snakes that we’ve mentioned. It is greyish-green, brown, or black with yellow or orange stripes and black bars on its lips. Plains garter snakes are found in the central and eastern regions of Montana. Although they can occur in most habitats, they are most often found at lower elevations near a source of water – such as swamps, ponds, and streams. Plains garter snakes are known for being particularly tolerant of cold weather and often emerge from their brumation on warm, sunny days to bask in the sun. Outside of their brumation period, plains garter snakes are usually active between April and October.
7. Western Hognose Snake (Heterodon nasicus)
The final black snake in Montana is the western hognose snake which is also known as the plains or prairie hognose snake. Although their appearance can vary, these snakes are typically a light or tan brown color with dark brown to black blotches – again quite similar to the prairie rattlesnake. However, the most distinctive feature of the western hognose snake is its upturned snout used for digging and burrowing the soil. Western hognose snakes are found in the central and eastern regions of the state up to the Rocky Mountains, or in any areas with loose soil. Western hognose snakes prey mainly on amphibians. They use the mild venom which is produced in their rear fangs to subdue prey. When threatened, western hognose snakes sometimes flatten their necks and act like a cobra but they are not dangerous to humans.
Up Next
Discover Montana’s Only Rattlesnake Species: Large and heavy-bodied, this reptile is the state’s only venomous snake. Find out all you need to know about it here.10 Snakes Found in Montana (1 is Venomous): What other snake species exist in the Treasure State? Find out here.Discover the 10 Largest Animals in Montana, and Where You’ll Find Them: What are the ten largest varieties of wildlife which call the state home? Discover the answers in this article.
