Long-term apparent survival of translocated gopher tortoises: A comparison of newly released and previously established animals

Published source details Tuberville T.D., Norton T.M., Todd B.D. & Spratt J.S. (2008) Long-term apparent survival of translocated gopher tortoises: A comparison of newly released and previously established animals. Biological Conservation, 141, 2690-2697.
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This study is summarised as evidence for the following.

	Action	Category
	Release reptiles outside of their native range Action Link
	Translocate reptiles away from threats: Tortoises, terrapins, side-necked & softshell turtles Action Link

Release reptiles outside of their native range

A study in 1994–2008 on a grassy island in Georgia, USA (Tuberville et al. 2008) found that following translocation to a previously unoccupied island along with provision of starter burrows, adult gopher tortoises Gopherus polyphemus had higher survival than juveniles and translocated tortoises had lower initial survival than established tortoises from a previous translocation to the island. Initial survival was estimated to be lower for newly released adults (1^st year: 75%) compared to established adults (98%), and lower for newly released immature tortoises (1^st year: 45%, 2^nd year: 79%) compared to established immatures (84%). Twenty-eight of 76 (37%) newly released tortoises were never recaptured. Between 1987–1993, between 25 and 30 unmarked tortoises of unknown origin were released on the previously unoccupied island and not marked until 1994. In 1994, a further 74 tortoises (23 males, 32 females, 19 unsexed immatures) were translocated from a development site in Georgia, USA. Each was permanently marked with unique notches on marginal scutes and PIT tags and provided with starter burrows. Turtles were trapped twice a year by bucket or wire traps placed in front of burrows in autumn and spring from 1994–1998.

(Summarised by: Maggie Watson, William Morgan)
Translocate reptiles away from threats: Tortoises, terrapins, side-necked & softshell turtles

A study in 1994–2008 on a grassy island in Georgia, USA (Tuberville et al. 2008) found that gopher tortoises Gopherus polyphemus translocated away from a development site and provided with a starter burrow had lower initial survival than established tortoises from a previous translocation. Twenty-eight of 76 (37%) newly released tortoises were never recaptured. Initial survival was estimated to be lower for newly released adults (1^st year: 75%) compared to for established adults (98%), and lower for newly released immature tortoises (1^st year: 45%, 2^nd year: 79%) compared to established immature tortoises (84%). In 1994, seventy-four tortoises (23 males, 32 females, 19 unsexed immature tortoises) were translocated from a development site in Georgia, USA. Each was permanently marked with unique notches on the shell and PIT tags and provided with a starter burrow. Between 1987–1993, a total of 25–30 unmarked tortoises of unknown origin were released on the island and not marked until 1994. Turtles were trapped twice a year by bucket or wire traps in autumn and spring from 1994–1998.

(Summarised by: Maggie Watson, William Morgan)