The plains garter snakes were released at the Condie Nature Refuge northwest of Regina on Saturday afternoon.
A family collected the snakes in the fall after they wriggled in through foundation cracks on the family's old farm house outside Regina.
Some of the snakes were kept awake over the cold months and cared for by Salthaven West, an animal rehabilitation facility in Regina.
But 99 spent the winter further north in Prince Albert under the care of three Saskatchewan Polytechnic students, who kept them in a refrigerator to put them into hibernation.
The students monitored their temperature and moisture over the winter and plan to compile their data for a report.
Joanne Marchand, the faculty supervisor for the project, says all 99 that were put into artificial hibernation survived and suffered no weight loss.