Eastern Massasauga rattlesnakes may communicate among themselves with chemical and physical cues, especially during breeding. These snakes detect prey with their sense of smell and with the heat-sensitive pits found on their faces. They are also sensitive to vibrations and have relatively good eyesight. Rattlesnakes also communicate warning signals and aggression to attackers with their rattling tail and by coiling up and striking.
Communication Channels: tactile ; chemical
Perception Channels: visual ; infrared/heat ; tactile ; vibrations ; chemical
Eastern Massasauga rattlesnakes are threatened or endangered throughout their range, as a result of human persecution and habitat loss. Their wetland habitats are often lost to draining projects and their upland habitats to agriculture and suburban development. Michigan is one of the few places where Eastern Massasauga rattlesnakes seem to be doing reasonably well, though populations are declining here as well. The status in Michigan is 'special concern'. In the USA, this rattlesnake is a candidate species being considered for federal protected status.
IUCN Red List of Threatened Species: least concern
Rattlesnake bites to humans are rare, but are potentially dangerous. Most people who are bitten by rattlesnakes have been attempting to hurt or handle them. Eastern Massasauga rattlesnakes have a potent venom but have relatively short fangs that often fail to penetrate clothing and can deliver only small amounts of venom with each bite. Rattlesnake bites are painful, with swelling and tissue damage near the bite site. Anyone who has been bitten by a rattlesnake should stay calm and seek immediate medical attention (NOT try to cut open the wound and suck it out, a popular folklore). Most people recover completely from rattlesnake bites.
Most rattlesnakes are shy and retiring and killing rattlesnakes is entirely unnecessary. Rattlesnakes found near homes may be removed to other areas, though it is likely that it is the humans who have intruded on a snake's traditional habitat.
Negative Impacts: injures humans (venomous )
Eastern Massasauga rattlesnakes are very important in controlling rodent populations throughout their range. Research on rattlesnake venom helps develop new medical technologies to treat heart conditions and other diseases.
Positive Impacts: source of medicine or drug ; controls pest population
These rattlesnakes are very important in controlling populations of rodents and other small mammals in their natural habitats.
Eastern massasauga rattlesnakes eat mainly small mammals such as voles, white-footed mice, jumping mice, and shrews. They sometimes also take other snakes, frogs, birds, bird eggs, and insects, especially when they are younger and smaller. Young eastern massasauga rattlesnakes entice frogs and toads to come closer by twitching their tail tips. These snakes usually strike their prey, then wait for them to die before eating them, but prey that aren't likely to fight back, such as baby mice or frogs, may be eaten without using venom.
Animal Foods: mammals; amphibians
Primary Diet: carnivore (Eats terrestrial vertebrates)
Eastern Massasauga rattlesnakes are native to the Nearctic region. They are found throughout the central United States, from southern Canada to western Arizona, south to the Gulf Coast of Texas, and east to Pennsylvania.
Biogeographic Regions: nearctic (Native )
Eastern Massasauga rattlesnakes are usually found in damp lowland habitats, including bottomland forests, swamps, bogs, fens, marshes, sedge meadows, and wet prairies. The name 'massasauga' means 'great river mouth' in the Chippewa language. These habitats are used by massasaugas from early fall to late spring. During the spring and summer months these snakes often move into drier, more upland habitats, such as grasslands and farm fields.
Habitat Regions: temperate ; terrestrial
Terrestrial Biomes: forest
Wetlands: marsh ; swamp ; bog
Eastern Massasauga rattlesnakes have been known to live in captivity for 20 years, but lifespan in the wild is unknown.
Range lifespan
Status: captivity: 20 (high) years.
Eastern Massasauga rattlesnakes are members of the pitviper group. This large group of species are members of a larger group, the vipers. Vipers all have enlarged, hollow fangs at the front of their mouth which are used to inject a modified saliva into their prey. This saliva is venomous and causes their prey to die. The gaping of the mouth as they bite causes the fangs to swing forward, jabbing the prey, then muscles in their head inject the venom. Most vipers wait until their prey are dead before eating them. Pitvipers also have sense organs on either side of their head, the 'pits', that detect heat. This is important because pitvipers tend to eat warm-blooded prey and they use their pits to locate them. Some pitvipers are known as 'rattlesnakes' because they have a series of segments at the end of their tail that are loosely connected and make a hissing rattle sound when vibrated by the snake. New rattle segments are added each time the snake sheds its skin, so by counting the rattles one can estimate how old the snake is. Rattle segments can be lost, though, so if a snake has 8 rattle segments it may well be more than 8 years old. All rattlesnakes also have cat-like pupils which are elliptical and oriented vertically in the eye.
Eastern Massasauga rattlesnakes are thick-bodied, medium-sized snakes, ranging in length from 47 to 100 cm as adults. This snake is marked with rows of dark, irregular blotches running the length of their back on a background color of gray, gray-brown, or brown. These dark blotches, and dark stripes on the tail, are often outlined in a lighter scale color, making them stand out against the background color. Many are strikingly beautiful. Their coloration makes them very difficult to see in the places where they bask or hide. Belly color is usually black with light mottling and their heads are triangular in shape. Some individuals are almost completely black. The scales are keeled (with a raised ridge down their center) and males are slightly longer than females. Newborn eastern massasauga rattlesnakes are born at 18 to 25.6 cm in length. They are similar to the adults but overall lighter in color and have only a single 'button' of a rattle. At birth young Eastern Massasauga rattlesnakes are capable of using their fangs and venom.
These snakes are sometimes confused with eastern timber rattlesnakes, which have tails that are almost completely black. Eastern Massasauga rattlesnakes have striped tails.
Range length: 47 to 100 cm.
Other Physical Features: heterothermic
Sexual Dimorphism: sexes shaped differently
Some large snakes, such as racers and milk snakes, may eat rattlesnakes. Hawks, herons, raccoons, and foxes may be able to kill them as well, and deer and pigs will trample rattlesnakes when they see them. However, by far the biggest threat to eastern massasauga rattlesnakes is humans, who have relentlessly pursued and killed these snakes throughout their range. Eastern massasauga rattlesnakes mainly avoid confrontation, they are usually not aggressive. They rely on their camouflage coloration to avoid being seen and will most likely freeze when approached. If an enemy comes too close these snakes will attempt to escape or will vibrate their tail as a warning. Most eastern massasauga rattlesnakes are hesitant to strike unless seriously harassed.
Known Predators:
Anti-predator Adaptations: cryptic
Eastern Massasauga rattlesnakes mate in the spring and fall. The females hold the babies inside their bodies for about 3.5 months then, rather than laying eggs as some snakes do, they give birth to live young. Females give birth to their 5 to 20 young in abandoned mammal burrows or fallen logs while living in their drier, summer habitats. Young snakes become sexually mature (able to have babies) in their third or fourth year.
Breeding interval: Females reproduce only every other year.
Breeding season: Eastern Massasauga rattlesnakes breed in the spring and fall, they give birth in August and early September.
Range number of offspring: 5 to 20.
Average gestation period: 3.5 months.
Range age at sexual or reproductive maturity (female): 3 to 4 years.
Range age at sexual or reproductive maturity (male): 3 to 4 years.
Key Reproductive Features: iteroparous ; seasonal breeding ; sexual ; viviparous
Female Eastern Massasauga rattlesnakes nurture and protect their young inside of their bodies while they're developing. The young remain near their mother for a few days after birth and then move away (disperse).
Parental Investment: pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Female)
The eastern massasauga (Sistrurus catenatus) is a rattlesnake species found in central and eastern North America from southern Ontario in Canada and throughout the Midwestern and Eastern United States. Like all rattlesnakes, it is a pit viper and is venomous.
Three subspecies were recognized for more than a century,[4] although research published in 2011 elevated two subspecies Sistrurus catenatus catenatus and Sistrurus catenatus tergeminus, to full species: the eastern massasauga (Sistrurus catenatus) and the western massasauga (Sistrurus tergeminus).[5] The status of the third subspecies was somewhat unresolved and it is tentatively recognized as the desert massasauga (Sistrurus tergeminus edwardsii) by some,[6] or synonymized with the western massasauga (Sistrurus tergeminus) by others.[7] It is currently thought that eastern massassauga is monotypic; i.e. has no recognized subspecies.[2]
Adults of S. catenatus are not large, ranging from 60 to 75 cm (24 to 30 in) in length.[8] Their color pattern consists of a grey or tan ground color with a row of large, rounded, brown/black blotches or spots down the center of the back and three smaller rows of alternating spots down each side. Solid black melanistic examples are also known, as well as cases where the back blotches join with those on the sides. Young massasaugas are well-patterned, but paler than the adults. They have heat-sensing pits on each side of their smallish heads, their scales are keeled, and their anal scales are single.
Common names of the massasauga include: massasauga rattlesnake, massasauga rattler (Ontario), black massasauga, black rattler, black snapper, gray rattlesnake (Iowa), little grey rattlesnake (Canada), muck rattler, prairie rattlesnake, spotted rattler, swamp rattler, dwarf prairie rattlesnake, eastern massasauga great adder, ground rattlesnake, Kirtland's rattlesnake, little black rattlesnake, Michigan point rattler (Michigan), prairie massasauga, rattlesnake, small prairie rattlesnake, snapper, swamp massasauga, swamp rattlesnake, and triple-spotted rattlesnake.[9][10]
The Native American word, "massasauga", means "great river-mouth" in the Ojibwe language and was probably given to describe grasslands surrounding the river deltas in Ojibwe country.[11]
S. catenatus is found in North America from Ontario, Canada and central and western New York throughout the Great Lakes region to the Midwest. It occurs in various habitats ranging from swamps and marshes to grasslands, usually below 1500 m elevation. The type locality given is "... on the prairies of the upper Missouri" (Valley, USA).[3] There have also been reports of a young man seeing one in the Burnt Lands of the Ottawa Valley.
The species S. catenatus is classified as least concern on the IUCN Red List of Threatened Species. The population trend is unknown.[1] The eastern massasauga has been listed as a candidate species on the United States Endangered Species Act since 1999.[12]
The eastern massasauga is listed as an endangered species in Illinois, Indiana, Iowa, Minnesota, Missouri (also considered extirpated), New York, Ohio, Pennsylvania, and Wisconsin.[13][14][15] Michigan, the only state in which it is not considered endangered, lists it as "special concern".[16] The subspecies is a candidate for federal listing.[17] As of 2016, the massasauga is listed as Threatened under the Endangered Species Act.[18]
The eastern massasauga is listed as threatened under both Ontario's Endangered Species Act, 2007, and the federal Species at Risk Act, and is protected under the Fish and Wildlife Conservation Act.[8][19] It is found only near the eastern shore of Georgian Bay, the Bruce Peninsula, the North Shore of Lake Huron,[20] Wainfleet Bog, and Ojibway Prairie.[21] It is becoming rare in Canada due to persecution and loss of habitat and is designated as "threatened" by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC),[22] as well as the Committee on the Status of Species-at-risk in Ontario (COSSARO).
In Pennsylvania, the species has experienced a rapid decline largely because of habitat loss. Historically, this has been due to human activity and more recently primarily from natural forest succession. By 1988, the snake had disappeared from half of the counties that constituted its historical range.[23] A 2003–2005 survey showed only four locations in two counties with confirmed populations.[24] It is classified as "critically imperiled" to "imperiled" in the commonwealth.[25]
The diet of S. catenatus consists of a variety of small vertebrates, including mammals, birds, bird eggs,[26] lizards, and other snakes, as well as invertebrates such as centipedes and insects.[27] Mammals and reptiles make up the bulk of their diet. Adults feed mainly on rodents (such as voles, white-footed mice, jumping mice, and shrews),[28] while juveniles usually prey on reptiles, more often lizards in western populations and snakes in eastern ones. Frogs also constitute an important part of their diet: Ruthven (1928) mentioned that in Michigan they made up the main portion of their diet. According to Klauber (1956), S. catenatus feeds on frogs more frequently than any other rattlesnake. In general, however, frogs are not an important part of the diet, although this does seem to be more typical in certain northern and eastern populations.[9]
The venom of S. catenatus is a cytotoxic venom, so it destroys tissue. It also contains specialized digestive enzymes that disrupt blood flow and prevent blood clotting. Severe internal bleeding causes the death of the small animals that this snake eats. After envenomation, the rattlesnake is able to withdraw from the dangers of sharp-toothed prey animals until they are subdued and even partially digested by the action of the venom.
S. catenatus is rather shy and avoids humans when it can. Most massasauga snakebites in Ontario have occurred after people deliberately handled or accidentally stepped on one of these animals. Both of these scenarios can be prevented by avoiding hiking through areas of low visibility (in rattlesnake country) when not wearing shoes and long pants and by leaving the snakes alone if encountered. Only two incidents of people dying from massasauga rattlesnake bites in Ontario have been recorded; in both cases, the victims did not receive proper treatment.[29]
The eastern massasauga (Sistrurus catenatus) is a rattlesnake species found in central and eastern North America from southern Ontario in Canada and throughout the Midwestern and Eastern United States. Like all rattlesnakes, it is a pit viper and is venomous.
