Sistrurus catenatus catenatus
Eastern massasauga
Photo by Terrence M. Cox
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Key Characteristics

The Eastern Massasauga is a small to medium-sized (average 18-30 in/46-76 cm), thick-bodied, gray, gray-brown or brown snake with a distinctive color pattern of dark brown rectangular or saddle-shaped blotches down the back and two or three additional rows of dark spots along the sides of the body. The underside of the snake is either solid black or black with some light mottling. The tail has alternating dark and light bands and a segmented rattle at the end. It also has a triangular-shaped head (i.e., widens at the back of the head and narrows at the neck), vertical slit-shaped pupils, and large, heat-sensing pits or openings between the nostrils and the eyes. Newborn massasaugas range in length from 7-10 in (18-25 cm) and have a single button or rattle at the end of their tails.

Status and Rank

  • State Status: SC - Special Concern (rare or uncertain; not legally protected)
  • US Status: C - Candidate species being considered for federal status
  • State Rank: S3S4 - Rank is uncertain, ranging from vulnerable to apparently secure
  • Global Rank:

Occurrences

County NameNumber of OccurrencesYear Last Observed
Alcona42005
Allegan162002
Alpena61995
Antrim32004
Arenac21986
Barry52000
Berrien72003
Branch11917
Calhoun72000
Cass82007
Cheboygan11992
Clare11932
Clinton42006
Crawford92003
Eaton31993
Emmet11955
Genesee52005
Grand Traverse22004
Hillsdale11979
Huron31908
Ingham22001
Ionia11960
Iosco122006
Jackson192007
Kalamazoo172005
Kalkaska72004
Kent11994
Lake31989
Lapeer31995
Lenawee31999
Livingston132007
Mackinac12005
Macomb11995
Manistee42003
Mason42003
Missaukee21995
Montcalm21994
Montmorency42003
Muskegon52005
Newaygo32005
Oakland222005
Oscoda11964
Presque Isle51996
Roscommon11994
Saginaw31993
Shiawassee11928
St. Joseph12001
Van Buren112001
Washtenaw162007
Wayne11858
Occurrence Map for [Sname]

Information is summarized from MNFI's database of rare species and community occurrences. Data may not reflect true distribution since much of the state has not been thoroughly surveyed.

Habitat

Eastern Massasaugas have been found in a variety of wetland habitats. Populations in southern Michigan are typically associated with open wetlands, particularly prairie fens, while those in northern Michigan are known from open wetlands and lowland coniferous forests, such as cedar swamps. Some populations of Eastern Massasaugas also utilize open uplands and/or forest openings for foraging, basking, gestation and parturition (i.e., giving birth to young). Massasaugas usually hibernate below the frost line in crayfish or small mammal burrows, tree root networks or rock crevices in or along the edge of wetlands or in upland areas with presumably high water tables. Massasauga habitats generally appear to be characterized by the following: (1) open, sunny areas intermixed with shaded areas, presumably for thermoregulation; (2) presence of the water table near the surface for hibernation; and (3) variable elevations between adjoining lowland and upland habitats.

Specific Habitat Needs

Downed woody debris needed in Bog, Emergent marsh, Northern wet meadow, Southern wet meadow, Intermittent wetland, Coastal plain marsh, Wet-mesic sand prairie, Wet prairie, Prairie fen, Northern fen, Rich conifer swamp, Northern hardwood swamp, Southern hardwood swamp, Floodplain forest, Northern shrub thicket, Southern shrub-carr, Mesic southern forest, Dry-mesic southern forest, Dry southern forest, Mesic northern forest, Dry-mesic northern forest, Dry northern forest, Oak barrens, Oak-pine barrens, Pine barrens, Mesic prairie, Dry-mesic prairie, Dry sand prairie, Poor conifer swamp Snag/cavity needed in Rich tamarack swamp, Hardwood-conifer swamp, Mesic sand prairie

Natural Community Types

Management

Protection of extant populations and suitable wetland and adjacent upland habitats is crucial for successful conservation of the Eastern Massasauga. Maintaining or restoring open habitat conditions is critical for this species. Fragmentation of suitable wetland-upland habitat complexes by roads or other barriers should be avoided or minimized. Land management practices such as timber harvesting, mowing, disking or prescribed burning should be conducted in such a manner so as to minimize the potential for adverse impacts to massasaugas (e.g., conducting management activities during the snakes’ inactive season (November through early March) or on days when snakes are less likely to be active on the surface during the active season). Protecting suitable hibernation sites also is critical. Hydrological alterations such as drawdowns should be conducted prior to or after hibernation to reduce the potential for causing winter mortality due to desiccation or freezing. Sudden and/or permanent increases or decreases in water levels during the active season also can cause adverse impacts. Education and outreach efforts to raise public awareness and understanding of the Eastern Massasauga also are critical for conserving this species. Any suspected illegal collection of Eastern Massasaugas should be reported to local authorities. Massasaugas that need to be moved or translocated should be relocated to suitable habitat as close to where snakes were found and ideally within the snake's home range and within the same wetland complex.

Active Period

Breeding from second week of July to fourth week of August

Parturition from first week of August to second week of September

Active from first week of April to fourth week of October

Survey Methods

Massasaugas typically are active between April and late October, and can be seen anytime during the active period. However, the best times to survey for this species are during spring emergence (i.e., April-mid-June) and during the mating, gestation and birthing period in mid- to late summer (i.e., late July, August and early September) for gravid females and young-of-the-year. Another survey window for this species is during fall ingress when snakes are moving to and congregating around hibernacula. Visual encounter surveys for this species consist of walking through suitable habitat and looking for snakes basking, foraging, traveling or resting under cover, particularly along the edge of open wetlands and uplands and near shrub, woody debris or other vegetative cover or cover objects. Massasauga observations should be documented with photographs and/or verified by a species expert.

More Information

See MNFI Species Abstract

References

Survey References

Technical References

Page Citation

Michigan Natural Features Inventory. 2007. Rare Species Explorer (Web Application). Available online at http://web4.msue.msu.edu/mnfi/explorer [Accessed Nov 23, 2009]