The Timid Snake

The Eastern Massasauga Rattlesnake or Sistrurus catenatus catenatus, is one snake that is more afraid of you than you are of it.  A timid rattlesnake found from Central New York and Southern Ontario to Southcentral Illinois, Eastern Iowa, and is thought to most densely populate Michigan.  Commonly found in wet areas such as lowlands, wet prairies, and marshes in which rodents, amphibians, and insects are in abundance.  The Eastern Massasauga rattlesnake can be identified by its typically gray or brownish gray coloration with darker brown spots that run the length of the body as well as a rattle, which in Michigan at least, is a dead giveaway because it is Michigan’s only rattlesnake.  A small snake, the Eastern Massasauga averages 2-3 ft. in length and while it is venomous, when compared to other rattlesnakes in the United States it has the least potent venom.  Besides being Michigan’s only venomous snake, the Eastern Massasauga Rattlesnake boasts a variety of attributes that make it a unique little snake.

Range.png
Range of the Eastern Massasauga rattlesnake. http://www.dec.ny.gov/animals/7154.html

Inhabiting a range throughout the Great Lakes states forces the Eastern Massasauga, like other rattlesnake species, to hibernate to avoid freezing temperatures in the winter months.  Eastern Massasauga rattlesnakes hibernate in old crayfish burrows and other areas in which the water table is close to the surface.  Amazingly, these rattlesnakes submerge themselves during hibernation to avoid long periods of sub-freezing temperatures.  They also tend to hibernate alone instead of communally as other rattlesnakes do.  While communal hibernation has been observed with Eastern Massasauga rattlesnakes as well as Massasaugas’ hibernating with other snake species, it is much more common to find them hibernating alone.

Crayfish Burrows .png
Abandoned crayfish burrows serve as excellent places for the Eastern Massasauga to hibernate in. http://herpcenter.ipfw.edu

The Eastern Massasauga rattlesnake is an ambush predator, positioning themselves in high density prey areas to increase their chances of catching a meal.  Like other vipers, they possess heat sensing pit organs between the eye and nostril on either side of the head.  These organs allow them to detect infrared radiation from warm bodied prey up to a meter away.  Once the rattlesnake bites and injects its prey with venom, it releases its prize to let the venom kill the prey.  This protects the snake from bites or other injuries that could be inflicted by the prey item before it succumbs to the bite.  Juvenile Eastern Massasaugas’ are more opportunistic predators, feeding on rodents, amphibians, lizards, insects, and even smaller snakes.  They also take a different approach when it comes to finding prey.  Juveniles use caudal luring, or using its brightly colored tail tip (only found in juveniles) to mimic a worm or small insect to entice its prey closer.

Infared .png
Thermal profile of a prey item. http://www.nature.com

Mating occurs in the months of April and May and roughly a year later the baby rattlesnakes are born.  The snakes are ovoviviparous, meaning that the eggs hatch within the female snake, and therefore are birthed live shortly after.  The Eastern Massasauga rattlesnake is polygamous (has more than one mate) and will mate every year or every other year producing 3-20 live young.  Once the snakes are born there is no parental care, although they might be found in the same area as their mother for several days after birth.  Male rattlesnakes will fight with other males during mating season in competition for the best mates, they fight by raising a third of their body and wrestling each other until one concedes.

zoo snake.png
Photograph taken by myself at the Lincoln Park Zoo                                                  http://www.lpzoo.org

Federally the Eastern Massasauga is listed as “Threatened” by the U.S. Fish and Wildlife Service, and while it falls prey to many predators, its main threat is habitat loss and fragmentation.  Due to an ever-expanding human population, wetlands (the habitat of the Eastern Massasauga) have decreased 50% in the Midwest alone.  Roads are also a formidable opponent of the snake, and many snakes are killed while trying to bask in the sun on a warm road.  Also, because they are venomous, many are afraid of the Eastern Massasauga and when they are found they will be killed.  Not knowing that these snakes are very timid by nature and are much more likely to try and escape then stay and bite a human.  By controlling rodent populations, this snake has helped humans far more than it has ever hurt them, and it is imperative that this snake continues to inhabit its natural range as to not disrupt the ecosystem.  The chances of you seeing this elusive and timid snake are slim to none, but if you happen upon one just remember, it is much more afraid of you than you are of it.

 

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s