Eastern
Massasauga Rattlesnake (Sistrurus
catenatus catenatus)
http://labs.russell.wisc.edu/zuckerberg/research/climate-change-vulnerability-assessment/
Systematics
The eastern massasauga is actually
considered a subspecies of the species S.
catenatus, with the other two being the desert (S. c. edwardsii) and western (S.
c. tergeminus) massasauga rattlesnakes. They belong to the order Squamata
and family Viperidae (vipers and pit vipers).
Ecology
http://www.machac.org/project_categories/featured-project/
The eastern massasauga ranges from
central New York and western Pennsylvania all the way through to Ohio,
southwestern Ontario, Michigan, Indiana, Illinois, southern Wisconsin, eastern
Iowa, southeastern Minnesota, and central Missouri. In PA, this rattlesnake
inhabits a couple of different habitats depending on the season, from open
fields to remnant prairies and shallow, open wetlands. During the winter, they
will find and burrow into previously dug-out tunnels and holes made by crayfish
and moles in the rush-sedge marshes and mixed forbs. Adult eastern massasaugas
prey on small mammals, typically rodents including meadow voles, short-tailed
shrews, and white-footed mice, but it may eat the occasional nesting bird or
frog. Broods average at about seven young every 2-3 years from mid-August to
September, but the brood can range from 3-19 snakes. It takes anywhere from 2-4
years to reach sexual maturity, but it’s lifespan can exceed 20 years.
http://www.arkive.org/parkhill-prairie-crayfish/procambarus-steigmani/image-G98970.html
and http://www.fcps.edu/islandcreekes/ecology/meadow_vole.htm
Reproduction
Mating seems to occur in late
July/August, with females giving birth to live young the following
August/September. Males compete for the females during the summer, and a female
will store deposited sperm until after hibernation in the spring. During gestation, the females will often bask
in exposed areas with little to no vegetation. The young actually develop in
eggs, but the eggs hatch while still within the female’s body, so the snakes
come out as live young.
Threats
The main threat to the eastern
massasauga population in PA is habitat loss driven by human activity and
natural forest succession. Wetland habitats that would be used for
overwintering are drained for farms or flooded, while forests reclaim the
fields and prairies used for food and reproduction. Eastern massasaugas are not
distance travelers, so they require the fields and wetlands close to prairies.
Towns, roads, and farm fields prevent migration between the areas for the
snakes, isolating them to small populations that ultimately die off. To a
lesser degree, the population was also affected by the outright killing of
eastern massasaugas by people because of their venomous capabilities. At one
time, many states had bounties on rattlesnakes like the eastern massasauga,
showing how much people went out of their way to kill them.
Management
In order to save the species, areas
with surviving populations should be secured and managed, with a goal of
increasing habitat area. Succession of woody vegetation should be controlled so
that the habitat is not lost, and secured areas should mitigate any harmful
effects done by human activity on the eastern massasauga or the habitat.
Precautions should be taken, like analyzing the impact a project might have on
the population beforehand. Additionally, education services providing accurate
information on the importance of eastern massasaugas meant for dispelling any
previous inclinations of the snake should be implemented, as people tend to
focus on the venom it carries and not the role it has in the environment.
References
Climate Change Vulnerability Assessments." Zuckerberg Lab. N.p., 20 Dec. 2013. Web. 18 Mar. 2015. <http://labs.russell.wisc.edu/zuckerberg/research/climate-change-vulnerability-assessment/>.
"Eastern Massasauga
Rattlesnake." USFWS: Eastern Massasauga Fact Sheet. U.S. Fish and
Wildlife Service, n.d. Web. 18 Mar. 2015. <http://www.fws.gov/midwest/endangered/reptiles/eama/eama-fct-sht.html>.
"ITIS Standard Report Page:
Sistrurus Catenatus Catenatus." ITIS Standard Report Page: Sistrurus
Catenatus Catenatus. U.S. Fish and Wildlife Service, n.d. Web. 18 Mar.
2015. <http://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=209510>.
Meadow
Vole." Meadow Vole. FCPS, n.d. Web. 19 Mar. 2015.
<http://www.fcps.edu/islandcreekes/ecology/meadow_vole.htm>.
"Parkhill
Prairie Crayfish Photo." Procambarus Steigmani. N.p., n.d. Web. 20
Mar. 2015.
<http://www.arkive.org/parkhill-prairie-crayfish/procambarus-steigmani/image-G98970.html>.
"Pennsylvania
Amphibian and Reptile Survey." MACHAC. MACHAC, n.d. Web. 19 Mar.
2015. <http%3A%2F%2Fwww.machac.org%2Fproject_categories%2Ffeatured-project%2F>.
Brittingham,
Margaret C., Timothy Maret, and Joseph Merritt. Terrestrial Vertebrates of Pennsylvania. Ed. Michael A. Steele. Baltimore: Johns
Hopkins University Press, 2010. Print.
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