Plains Gartersnake

The Plains gartersnake once lived in the prairies of Wyandot and Marion counties but today is only found at Killdeer Plains Wildlife Area.  Due to habitat loss, this docile, non-venomous snake was designated as a state endangered species in 1974.  Dalrymple and Reichenbach (1984) determined the density of the snake at 52-123 snakes per hectare.  In 1998, Reichenbach duplicated the study and reported a 94% decline of the snakes.  Annual surveys of the plains gartersnake have continued at Killdeer.  In addition, pregnant snakes were collected in 1999 and 2000 to establish a captive-breeding colony and learn more about the snake’s biology.  Several additional wild snakes have been added to supplement the captive-breeding colonies.  Eighty-nine neonates produced from breeding colonies established at the Columbus and Cleveland Zoos have been released at Killdeer to augment the wild population from 1999-2002.  A Population Viability Analysis completed in May 2003 indicated that the most feasible method to increase the wild population of snakes would be to retain neonates until their juvenile stage and then release them versus the release of newly born snakes as previously done.  Twelve 1-year-old juvenile snakes born at the zoos were released during the summer of 2010.  All the juvenile snakes were implanted with a passive integrated transponder (PIT) to facilitate their identification during later mark-recapture surveys. Eleven of the 1-year-old snakes were also implanted with radio transmitters to track their movement and determine habitat use following release.  To date the total neonate production from the captive colonies is 257 live neonates of which 194 have been released (50 as neonates and 145 as headstarted 1-year old juveniles).

Survey details and historical data can be found in the Grassland Species Overview section of the Wildlife Population Status and Hunting Forecast.