New Arrivals: Eastern Massasauga Rattlesnakes

Lincoln Park Zoo is excited to announce the arrival of nine sweet and slithery new residents. On January 14, a female eastern massasauga gave birth to nine offspring. As the species is endangered and notoriously difficult to breed, this is a big conservation win. In fact, this is the first birth for this species at the zoo in almost 10 years.

Eastern massasauga rattlesnakes are ovoviviparous, which means that they internally incubate their developing young inside eggs until those eggs are ready to hatch inside the mother’s body. The female will then give live birth to the newborn snakes after a gestation period of three and a half months. In many rattlesnakes, maternal protection of newborns has been documented, and some these young snakes were observed still staying close to their mother.

The 11-year-old female was born at Lincoln Park Zoo, while the father is a 10-year-old male who has lived here since 2021. This birth is the result of a recommendation by the Eastern Massasauga Rattlesnake SAFE (Saving Animals From Extinction) program of the Association of Zoos and Aquariums. Staff believe the female is part of a third generation of snakes from potentially the last massasauga population living in the northern suburbs of Cook County. That makes these new additions true locals!

Images courtesy of Animal Keeper Bryan Summerford

Eastern massasauga rattlesnakes are small pit vipers listed as threatened under the Endangered Species Act of 2016. While they are venomous, they are also quite shy, so humans rarely encounter them and bite incidences are very low. Their populations, which are spread east to New York, west to Iowa and Missouri, and north to southeastern Ontario, suffer from habitat loss in the wetland environments they prefer.

Lincoln Park Zoo, along with state and national authorities and AZA, is working to conserve these animals. The young rattlesnakes are currently behind the scenes, but the mother can be seen in her habitat at Regenstein Small Mammal-Reptile House.