frequently asked
q u e s t i o n s
critter
f i e l d   g u i d e
what is it?
g u e s s   g a m e
ask jim
y o u r   q u e s t i o n s
critter care
i n s t r u c t i o n s
links
f o r   m o r e   i n f o
Critterguy / FAQ / Snakes
FAQ: Snakes

I saw a strange snake in my yard today and was wondering if it could be a rattlesnake. How can I tell the difference between harmless and dangerous snakes?

Most snakes are harmless and beneficial. Michigan's only venomous snake has rattles and eliptical pupils in its eyes. Native snakes with pointed tails and round pupils are non-venomous. Some people have snake-phobia.

eastern Massasuga rattlesnake
eastern Massasuga rattlesnake
Remedies include:
•   Exclusion: (Seal up holes in basement and/or foundation. Seal cracks around porches, steps, etc.).
•   Change environment: (Snakes need cover, food. Seal under decks; trim bushes off ground, keep thick shrubs and mulches away from house foundation. Mow lawn short, and keep thick, natural plantings and wood piles at periphery of yard. Pick up all lumber and debris.)

•   Repellents: (Commercial repellents are available for use around houses, but results are debatable.)

•   Trapping and removal: (Harmless species can be captured with thick-gloved hand or "swept" into boxes and trash cans and moved to natural habitat. Snake traps are available commercially, but effectiveness is inconsistent. For venomous snakes, it is best to get professional assistance for capturing and removing them.)

•   Killing: (Not recommended; some species are becoming rare and are legally protected. Our rattlesnake is unlikely to bite unless it is attacked.)


More Detailed Information

Michigan has only one species of venomous snake—the Massasauga Rattlesnake.

eastern Massasuga rattlesnake
eastern Massasuga rattlesnake
They are found throughout the Lower Peninsula and on Bois Blanc Island. There are no venomous snakes native to the Upper Peninsula. Massasaugas are rare, but might occur anywhere there are marshy or swamp wetlands bordered by undeveloped upland habitats (meadows, old fields, open woodland). They use the wetlands from fall through spring, and often move to drier habitats in summer.

All other native Michigan snakes (17 species) are non-venomous, and basically harmless to humans if not handled or harmed. (Almost any animal, from chipmunks to chickadees, can bite in self-defense!)

The quickest way to tell a rattlesnake from any other native snake is to look at the tail tip for rattles (any Michigan snake with a sharp, pointed tail tip is not venomous). Occasionally a harmless snake will lose its tail tip to a predator, but a rattler will never have a sharply pointed tail, even if rattles break off. Also, rattlers have cat-like eyes in bright light, while all other native snakes have round pupils. You can see feature this even from several feet away!

northern water snake
northern water snake
The most common snakes in Michigan are the harmless garter and ribbon snakes, which almost always have lengthwise, light-colored stripes running down the back. Many people recognize "striped" snakes as harmless, but are more suspicious when they see a snake with a blotchy pattern on the back. Two common "blotchy" snakes of southern Michigan are the Northern Water Snake and the Eastern Milk Snake. Water snakes are found along river and lake edges, while milk snakes often inhabit upland woods and farming areas, and often turn up in suburban yards. Because milk snakes will often vibrate their tails when threatened, they are surely the one harmless species most often confused with the rattlesnake.

The differences between a milk snake and a massasauga would be quite clear if you saw the actual animals side by side. The milk snake has a narrow body, with a neck not much smaller than the body, and a smallish narrow head. The pupils in the eyes are round in daylight. The tail tapers to a point. The blotches down the back are usually reddish brown, bordered by black, on a tan or gray background.

eastern hog-nosed snake
eastern hog-nosed snake
The rattler, on the other hand, has a chunky body contrasting with a very narrow neck and a wider head. The heat-sensing "pits" are visible between the eyes and nostrils. The pupils are vertical (cat-like) in daylight. The tail ends in a small segmented rattle. The blotches are dark brown or dark gray, bordered by black, on a grayish or gray-brown background (though some rattlers are very dark with an obscured pattern).

Massasauga populations are declining due to persecution and habitat loss. The Michigan Department of Natural Resources is surveying previously known and potential massasauga habitats across the state to see where they still exist. These little rattlers are not considered deadly to humans, but bites are painful and can cause complications. Simply leaving the snakes alone is the best defense—they are usually very shy don't want confrontation with humans.


For descriptions of these and other Michigan snakes, check out our "Critter Field Guide"


Butler's garter snake
Butler's garter snake
Acknowledgement

James Harding
MSU Museum
Michigan State University
East Lansing, MI 48824
(517) 353-7978
hardingj@msu.edu

© Copyright 2004. All Rights Reserved.