Michigan Herps

Eastern Massasauga Rattlesnake

Sistrurus catenatus catenatus

Michigan is home to only one species of venomous snake, the Eastern Massasauga Rattlesnake. The name Massasauga comes from the Chippewa language which means, "great river mouth." This name is fitting since the Massasauga's primary habitat is floodplain of rivers and streams. These snakes are generally shy and secretive, which makes them a very rare sight. Massasaugas spend most of their time hidden in long grass and shrubbery charachteristic to prairies and marshes. If encountered, these snakes will try to get away and avoid confrontation with humans. It is only when they are corned, harassed, or alarmed that they will become defensive and hold their ground. They will not hesitate to bite if they are trying to be caught. Although they are declining throughout most of their range, Massasaugas are doing quite well in Michigan as opposed to other states. In all other states they are found; Wisconsin, Illinois, Iowa, Missouri, Indiana, Ohio, New York and the province of Ontario in Canada, Massasaugas are classified as either extirpated (extinct locally), endangered, or threatened. In Michigan, they are listed as a SPECIES OF SPECIAL CONERN, which means it is illegal to harass, collect, or kill a Massasauga. If you encounter a Massasauga, admire them with a respectful distance and take photographs.

Description

Massasaugas are a small to medium sized rattlesnake that are members of the Pygmy rattlesnake family, Sistrurus. These rattlesnakes differ from the Crotalus family because of the nine enlarged scales that are found on top of the head. Massasaugas are brown, gray, or even black with dark saddles that run down the middle of their backs. In addition, they have 2-3 rows of dark blotches on their sides. Their belly is a dark gray or black color, white the underside of the chin is white. They also have a charachteristic dark band that runs diagonally across their eye to the back of their jaw, this band is usually bordered by a lighter color as shown at right. Although adult size is only 2-3 feet, Massasaugas are stockly little snakes. Like all pitvipers, because they are stout bodied, they are slow and sluggish snakes. If cornered or frightened, Massasaugas will coil, rattle, and even strike if provoked. Like other members of the Pit Viper family (Crotalidae), Massasaugas have a heat sensing pit inbetween their eye and nostril. This pit, allows the snake to feel and see heat, which helps it distinguish prey during the cover of night and alerting them to predators.

 Venom Toxicity

All vipers produce venom within their venom glands near the back of their head, which helps give a viper its classic triangular head. Massasaugas have a highly toxic venom that is much more toxic than a lot of other rattlesnake species. In fact, drop for drop, an Eastern Massasauga's venom is more toxic than the venom of a Timber Rattlesnake (Crotalus horridus). But, because of its small size, Massasaugas are not able to inject a lot of venom, so bites are nowhere near as serious as a Timber Rattlesnake bite. Massaugas venom is a combination of hemotoxins and cytotoxins. Hemotoxins attack the blood and cause massive hemorrhagic effects, while cytotoxins attack the tissues, causing lots of tissue damage. Massasauga bites can be extremely painful, but are almost never fatal. 25-45% of bites are dry bites, which means the snake does not inject any venom. Although a bite and envenomation from an Eastern Massasauga is not considered to be serious, it is wise to go to a local hospital and receive medical treatment if you are bitten.

Distribution &

Habitat

Eastern Massasaugas are found throughout the entire lower peninsula in isolated populations where good wetland habitat is still present. They or any other venomous snake have not been found or documented to inhabit the upper peninsula. The strongest populations are found in the northern part of the lower peninsula near Lake Huron and in the southeast corner of the lower peninsula. Many other populations throughout the state were wiped out during the past century due to habitat loss, persecution, and senseless killing of Massasaugas. They also have been documented to be found on Bois Blanc Island in Lake Huron. These snakes typically inhabit bogs, wet prairies, fens, tamarack swamps, and other wetland habitats during the spring and fall months. During the mid-summer months (May-August) they move upland into drier woods and prairies in order to find mates and reproduce. Large gravid (pregnant) females can be seen sunning themselves in the open during these months in prairie environments, while males can be seen moving back and forth on the borders of prairie and wetlands habitat. Also, as the days get warmer Massasaugas become more and more nocturnal. During the winter months, Massasaugas move back into the wetlands in order to den up for the winter. They use abandoned crayfish burrows, old root systems, and other animal burrows as dens for the winter.

                                                                                                                                                          Diet

Massaugas rely on their camouflage and reclusive behavior to catch their prey. A snake will sit and wait for a small prey item such as a mouse to wander too close and then strike and envenomate its prey. The venom is very toxic and will kill the prey in only a few seconds, allowing the Massasauga to use its tongue to follow the trail of its prey and eat it. Massasaugas eat a wide variety of prey. As a young age, they may eat insects that are large in size. As adults, Massasaugas consume frogs, toads, voles, and their favorite food; mice. Although they are an efficient predator, Massasaugas are vulnerable to predators that are larger than them. Eagles, hawks, herons and larger snakes such as the Blue Racer are known to eat Massasaugas. Yet they are rarely eaten due to their reclusive behavior.

Encounters with Massasaugas

With all the time I spend hiking in southeast Michigan, I have had my fair share of encounters with massasauga rattlesnakes. I wanted to give a short summary of some of my more memorable encounters with these snakes to try and show that they aren't an aggressive species at all, and also to show how unique the species is.

July 18th, 2007

The evening of July the 18th was a hot and humid one. Temperatures had reached the mid 90s during the late afternoon, and the evening temperatures were holding in the low 80s with very high humidity. I decided to go out for an evening hike at a local area in hopes of turning up a few snakes out on the move. The typical garter snakes and ribbon snakes were seen of course, but things changes as I walked a service drive past a hotspot for massasaugas within the area.

As I came around a corner on the gravel service drive, I spotted a large stocky snake making its way across the road and immediately knew that it was a large massasauga rattlesnake.

The snake coiled almost immediately and sat defensively for a few minutes to allow me to snap a few photographs, it was and still probably is the most attractive massasauga I've seen.

August 25, 2007

Later on in the summer of 2007, I was out on an evening hike similar to the hike I took on the night of July 18th. It was also another hot & humid evening, and as always there were quite a few snakes on the move. But I did not expect what was about to happen, it would be one of the most exciting experiences in the field that I've ever had. Things got interesting as I noticed movement ahead of me in the trail...

It was a large male rattlesnake making its way back towards some heavy cover, a really healthy looking snake...

Seeing one massasauga in a single night is something to be excited about, but seeing multiple specimens in single outing is unheard of this late in the year in Michigan. The cover becomes much thicker and the odds of even seeing one snake are very slim, so seeing two is extremely unlikely. Less than ten minutes after photographing the first snake, I was startled by a buzzing coming from a sedge tussock on the side of the trail as I passed. It sounded like a rattlesnake, and sure enough I had startled a nice looking snake...

I moved some of the brush to the side to reveal this nice looking specimen, it didn't move a muscle for the few minutes that I photographed it.

April 11, 2008

As the cold weather finally snapped in mid-April of 2008, it was finally time for snakes to be out and on the move. On one afternoon, the sun was shining and it was perfect for some snakes to be out sunning themselves, so I went for a little hike.

The cover was relatively sparse and even then it was tough to spot anything. But in one particular clearing, I spotted a stocky snake trying to remain invisible with its cryptic camouflage.

The snake was a large gravid female. She was one of the larger and heavier massasaugas that I've seen, probably close to thirty inches in length.

April 20, 2008

After several weeks of planning, I drove down to northern Indiana to meet up with good friends Andrew Hoffman & Todd Pierson in hopes of finding their first massasauga rattlesnake. Because of turkey hunting, we weren't allowed to get onto state land until 1 in the afternoon. We saw several Blanding's Turtles and other snakes, but did not reach decent habitat until one. We finally arrived at a very good looking fen, we set in a little after one o'clock and went for a hike.

We hadn't been hiking for even five minutes when I looked down to my right in a sedge tussock and saw what appeared to be a coiled snake sitting deep in cover. There was no question what our snake was from the moment I spotted it, definitely a massasauga rattlesnake.

We coaxed the snake out and it turned out to be the same large female that Todd & Andrew had spotted a day earlier. But nonetheless, the other members of the group were ecstatic finally see a massasauga.

May 2, 2008

On an overcast and muggy morning, I went for a short hike in a new fen that I found near my house. The habitat was very similar to places where I've encountered massasauga rattlesnakes in the past, so I knew that there was a chance that I might bump into one while on my hike.

About twenty minutes into my hike, I spotted a dark colored coil in some brush. It was a little male massasauga trying to warm himself in the overcast morning, he was a very feisty little snake and I was very cautious as I photographed him.

May 27, 2008

In late May of 2008, I visited a park that I frequently hike at in hopes of coming across whatever herps I could find. The park is a well known site for massasaugas rattlesnakes and many studies on them have been done here. The signs give visitors a clear warning to stay on the trails in order to avoid the park's notorious inhabitant.

At around 11:30 AM, I noticed a dark shape out of the corner of my eye. A mere five feet from the edge of the trail sat a big gravid female massasauga, sunning herself in the morning sun. She was absolutely beautiful!

April 25, 2009

On a beautiful & sunny April morning, my dad and I took a walk at one of our favorite areas for a morning hike. The weather was 71 degrees by 10 AM and was perfect for snakes to be out basking to warm themselves for the day. We walked a trail that took us around the edges of a good sized fen, we carefully scanned the open sunny patches for anything that looked snakelike.

At around 10:30 AM, I spotted a nice looking snake trying to conceal itself within the brush of the fen. It was a small male massasauga rattlesnake, and a beauty at that.

The snake was very cool tempered and was cooperative enough for my dad and I to snap a few photos of it before letting it go on its way.

June 27, 2009

After getting off of work around 5 PM on a warm June evening, I headed over to my favorite area to hike which is a mere two miles up the road from the golf course I work at. About a half hour into my walk, a dark coil in some thick cover caught my eye.

I was able to gently coax the snake out for some pictures. It was a nice-sized gravid female that is much darker than any specimen I've ever seen. I snapped a couple quick shots for voucher purposes.

She settled down nicely and allowed me to grab some really nice shots of her, it took me a good 15 minutes to get shots I was satisfied with.