While it is unlikely you will ever find a venomous snake in Massachusetts, odds are good that if you spend any time outdoors you will eventually encounter one or more species of harmless snakes. Five common snakes account for the majority of sightings in Massachusetts.
Undoubtedly, the most commonly encountered snake is the garter snake. This prolific, adaptable species thrives in suburban habitats and often utilizes the shelter provided by shrubbery, mulch, stonewalls and cracked masonry around houses. Active by day, it is often observed in the morning, warming itself on stairs and sidewalks exposed to the sun.
The milk snake makes use of many of the same habitats as the garter snake and will sometimes enter buildings in search of mice, its favored prey. Though quite common, its secretive nature and nocturnal habits make it less likely to be encountered than the garter snake. Occasionally, it can be seen sunning itself on spring and early summer mornings.
A small, common, secretive species, the ringneck snake is rarely found in the open. This inoffensive, pretty snake with the bright band around its neck is sometimes encountered in damp or dirt-floored basements that offer ample food in the form of salamanders and insects.
Frequently encountered by fishermen and boaters, the water snake is one of our most prolific species and can be found in virtually all pond, river and wetland habitats throughout the state. Water snakes are often reported by home-owners who find them in the spring as they disperse from hibernation sites. Though large individuals may look quite sinister with their triangular heads and heavy bodies, these stocky eaters of fish and frogs are harmless and should not be confused with the venomous cottonmouth "water moccasins" of the southeastern states.
The "blacksnake" or black racer is a long, slender "sight-hunter" known for its speed and agility. (Its top speed is actually only 3.6 miles per hour.) It is usually encountered in rural habitats of mixed brush, field and forest. Although this alert, inquisitive reptile often raises its head up to observe approaching people or other disturbances (and may even follow people for short distances to satisfy its curiosity) it quickly turns tail and flashes away at the slightest hint of danger.
Though relatively rare, a chance encounter with a hognose snake is always memorable. This harmless "great pretender" puts on such a fearsome display when alarmed that it actually looks and sounds far more dangerous than either of our venomous snakes! Sometimes called the "puff adder," this habitual eater of toads will inflate its body, hiss loudly, lunge about ferociously and spread a surprising cobra-like hood. Despite this impressive appearance, it almost never bites.
If this incredible bluff fails to drive off the offender, the hognose will writhe about, vomit, roll over on its back and let its tongue loll out. In short, it puts on the appearance of a thoroughly dead snake. If turned upright, the snake will immediately roll on its back again. When the danger is past, however, the hognose will cautiously raise its head, turn over, and be off about its business.
There are only two venomous snakes in Massachusetts - the timber rattlesnake and the copperhead. (Contrary to popular belief, there are no venomous "water moccasins" in the Bay State, only harmless water snakes.) Statewide, populations of our two endangered venomous snakes are believed to number no more than a few hundred individuals. Due to a host of problems, these populations are probably still declining despite rigorous efforts to protect them. Our "rattlers" are now known to exist at only a dozen or so widely scattered sites in mountainous regions of the state; the distribution of copperheads is even more restricted. As a result, most of Massachusetts is completely devoid of venomous serpents.
The chance of receiving a venomous snake bite is further reduced by the fact that both species are shy and reclusive. Like all snakes, they will bite people only in self defense. If you do not willfully seek out and attempt to confront these species, the chances of being bitten by either are negligible. The toxicity of their venoms tends to be highly overrated; only one person has ever died of snakebite in Massachusetts, and that was more than 200 years ago.
Always keep in mind that many harmless snakes resemble venomous snakes in pattern and behavior. Milk snakes, water snakes, hognose snakes and other banded or blotched species are frequently mistaken for copperheads. Milk snakes, black racers and black rat snakes are often misidentified as rattlesnakes because they vibrate their tails rapidly when alarmed. The overwhelming majority of reports of encounters with poisonous snakes in New England are nothing more than cases of mistaken identity.
Snakes encountered around the home are almost certainly harmless and non-venomous. With just a little effort you can confirm this with an identification. It is a simple matter to learn to recognize our five common snakes at a glance. More secretive and rarer species can be easily identified through use of the identification guide. It is a curious fact that when we have the ability to put a name to something and understand its motivations, it tends to lose the power to frighten us.