The mission of the U. Fish and Wildlife Service's Endangered Species program is c onserving and restoring threatened and endangered species and their ecosystems.
Find a location near you ». The U. Fish and Wildlife Service is protecting the eastern massasauga rattlesnake Sistrurus catenatus as a threatened species under the Endangered Species Act. We also determined that designating critical habitat for the eastern massasauga is not prudent.
To list the eastern massasauga as threatened, we first published a proposed rule in the Federal Register on Sept. We then gathered and analyzed comments and new information received during that comment period. Based on that analysis, we determined that the eastern massasauga may become endangered in the foreseeable future, which is the definition of a threatened species.
We published a final rule in the Federal Register on September 30, , that adds the eastern massasauga to the list of threatened species.
The final rule has an effective date of October 31, Eastern massasaugas are small, thick-bodied snakes that live in wetlands and use adjacent uplands. Adults average about 2 feet in length and have heart-shaped heads and vertical pupils. Habitat that massasaugas use varies with the season. After coming out of hibernation in spring, they travel to the habitat they use from spring through fall their active season , which varies considerably among individuals depending on region and local conditions.
Generally, eastern massasaugas use wet prairies, marshes, low areas along rivers and lakes and adjacent uplands. Foraging habitat can be floodplain, riparian, lowland and upland forest that provides an adequate abundance of suitable prey.
Foraging habitat usually has an open canopy and a sedge or grass ground cover. Eastern massasaugas tend to use areas with a mix of sparse plant cover and sunny areas so they can bask in the sun to regulate their temperature, but they also need shady areas nearby for protection from predators and as a source of prey. In fall they move to areas where they will hibernate over winter. These are almost always wetlands, and they frequently hibernate in crayfish burrows, or under tree roots or logs.
Like all rattlesnakes, eastern massasaugas bear live young. The young actually hatch from eggs while still in the female's body. Adult females tend to bear young every other year. Eastern massasaugas eat small rodents like mice and voles, but they sometimes eat frogs and other snakes. They hunt by sitting and waiting.
Massasaugas can find prey by sight, by feeling vibrations, by sensing heat given off by their prey, and by detecting chemicals given off by the animal like odors. Heat sensitive pits near their eyes alert the snake to the presence of prey. Eastern massasaugas currently live in an area that extends from central New York and southern Ontario to southern Iowa and includes eight states and one Canadian province.
Historically, eastern massasaugas also occurred in small parts of Minnesota and Missouri. The range of the snake has generally remained the same over time; however, the number of populations and the numbers of snakes within populations have steadily declined. Currently, we find only small, isolated populations of the massasauga throughout its former range.
In every state and province within this range, the eastern massasauga is state- or province listed as endangered, threatened, or a species of concern. The Service listed the eastern massasauga as threatened because of loss of populations throughout its range, declines in the number of individuals within those populations and the fact that threats will continue to cause declines into the future.
If we continue to lose eastern massasauga populations, the species is likely to face extinction in the future. We know of historical populations, of which have been lost and the status of 84 is uncertain — with the likelihood that many of those populations have also been lost.
Remaining habitat for the snake must be preserved, and negative public attitudes toward these nonaggressive animals must be reversed. Much of the threat to rattlesnakes comes from two things that seem contradictory: the public's fear of snakes, and the thousands of rattlesnakes that are harvested from the wild each year for their meat and skin.
Another major threat is a peculiar cultural institution called rattlesnake roundups, during which people catch and slaughter hundreds of snakes, with awards going to the contestants who capture the biggest rattlers. Not everyone thinks that the eastern diamondback needs protection. The rodeo used to catch snakes a year and now catches 70, some of which are given to researchers.
Others are used to teach dogs to avoid rattlesnakes. The rodeo also serves fried western diamondbacks from Texas. But Mark Sasser, a non-game wildlife coordinator with the Alabama Department of Conservation and Natural Resources, disagreed with Childre: "It is evident that there are declines in not only the eastern diamondback, but also in a lot of species that are associated with long leaf pine ecosystems," he told the newspaper.
It is not a judgmental opinion; it is a scientific fact. The next step is for the FWS to review the petition, a process that normally takes a year, but may take longer due to the Service's recent agreement pdf to review the species already in its species-protection backlog with a goal of moving them toward being listed as endangered species, a process that will take several years. Flag photo via Flickr. Rattlesnake photo via Wikipedia.
Males are active at this time, searching for females that have released pheromones chemical attractants. Mating occurs in spring or fall; the females give birth to an average of 9 young in August to late September range young.
This snake is ovoviviparous. Eggs are retained and hatched internally, resulting in live birth. Young emerge singly from the female, encased in a transparent membrane, which is shed in a few minutes. The 8- to inch long young are born with a single, tiny rattle segment button , venom, and fangs. They receive no maternal care, but are ready to fend for themselves. Males are sexually mature at about 5 years of age, while females mature at 7 to 10 years of age.
Females breed every third or fourth year. The average lifespan of rattlesnakes is years; therefore, a female may only reproduce as few as 3 to 5 times in her lifetime. Rattlesnake populations take a long time to stabilize after losing a significant number of breeding individuals due to their low reproductive rate.
Interesting Facts: Rattlesnakes also known as pit vipers are ambush predators that patiently wait for prey to come within reach. They use a keen sense of smell and sensory pit organs to find prey. The pit organs are located in a cavity on each side of the head between the nostril and the eye. They enable the snakes to seek out and strike accurately at objects warmer than their surroundings; this adaptation helps the snakes prey on nocturnal mammals. And the number of people who are bitten by snakes during outdoor activities is very low.
Those most likely to be bitten are snake handlers who either keep venomous snakes in captivity or work with them professionally. Nevertheless, malicious killings by those who perceive the snake as a threat are contributing to its decline. All of these species — even the rattlesnakes — should be allowed to exist.
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