Intact landscape promotes gene flow and low genetic structuring in the threatened Eastern Massasauga Rattlesnake

Ecology and Evolution
By: , and 



Genetic structuring of wild populations is dependent on environmental, ecological, and life-history factors. The specific role environmental context plays in genetic structuring is important to conservation practitioners working with rare species across areas with varying degrees of fragmentation. We investigated fine-scale genetic patterns of the federally threatened Eastern Massasauga Rattlesnake (Sistrurus catenatus) on a relatively undisturbed island in northern Michigan, USA. This species often persists in habitat islands throughout much of its distribution due to extensive habitat loss and distance-limited dispersal. We found that the entire island population exhibited weak genetic structuring with spatially segregated variation in effective migration and genetic diversity. The low level of genetic structuring contrasts with previous studies in the southern part of the species’ range at comparable fine scales (~7 km), in which much higher levels of structuring were documented. The island population's genetic structuring more closely resembles that of populations from Ontario, Canada, that occupy similarly intact habitats. Intrapopulation variation in effective migration and genetic diversity likely corresponds to the presence of large inland lakes acting as barriers and more human activity in the southern portion of the island. The observed genetic structuring in this intact landscape suggests that the Eastern Massasauga is capable of sufficient interpatch movements to reduce overall genetic structuring and colonize new habitats. Landscape mosaics with multiple habitat patches and localized barriers (e.g., large water bodies or roads) will promote gene flow and natural colonization for this declining species.

Study Area

Publication type Article
Publication Subtype Journal Article
Title Intact landscape promotes gene flow and low genetic structuring in the threatened Eastern Massasauga Rattlesnake
Series title Ecology and Evolution
DOI 10.1002/ece3.7480
Volume 11
Issue 11
Year Published 2021
Language English
Publisher Wiley
Contributing office(s) Great Lakes Science Center
Description 13 p.
First page 6276
Last page 6288
Country United States
State Michigan
Other Geospatial Bois Blanc Island
Google Analytic Metrics Metrics page
Additional publication details