Study

The importance of including survival release costs when assessing viability in reptile translocations

  • Published source details Bertolero A., Pretus J.L. & Oro D. (2018) The importance of including survival release costs when assessing viability in reptile translocations. Biological Conservation, 217, 311-320.

Actions

This study is summarised as evidence for the following.

Action Category

Release captive-bred reptiles into the wild: Tortoises, terrapins, side-necked & softshell turtles

Action Link
Reptile Conservation
  1. Release captive-bred reptiles into the wild: Tortoises, terrapins, side-necked & softshell turtles

    A replicated study in 1987–2015 in sand dune and mixed forest habitats in Spain and Minorca (Bertolero et al. 2018) found that many captive-maintained, released Hermann’s tortoises Testudo hermanni hermanni survived and that survival rates of released tortoises increased three years after release. During the first two years after release, average survival rates of translocated tortoises were 44–90% in Spain (66 individuals) and 79–85% in Minorca (48 individuals). In the third year after release, survival rates of translocated tortoises in Spain (98%) were similar to wild-born tortoises (98%) but survival rates of translocated tortoises in Minorca (89%) were lower than wild-born tortoises (97%). Body condition of tortoises before release did not affect whether or not a tortoise was subsequently found dead or alive (see original paper for details). Tortoises were maintained in captivity, though their origin and total time in captivity was unknown. In Spain, 66 captive tortoises were released into a protected reserve in four batches: September 1987, May–August 1988, March 1997 and September 1998. In Minorca, 48 tortoises were released in March–April 2004. The amount of time tortoises had spent in captivity prior to release was unknown. Tortoises were monitored for 4–10 days a year (Spain: 28 years; Minorca: 14 years) using capture-mark-recapture surveys.

    (Summarised by: Katie Sainsbury)

Output references
What Works 2021 cover

What Works in Conservation

What Works in Conservation provides expert assessments of the effectiveness of actions, based on summarised evidence, in synopses. Subjects covered so far include amphibians, birds, mammals, forests, peatland and control of freshwater invasive species. More are in progress.

More about What Works in Conservation

Download free PDF or purchase
The Conservation Evidence Journal

The Conservation Evidence Journal

An online, free to publish in, open-access journal publishing results from research and projects that test the effectiveness of conservation actions.

Read the latest volume: Volume 19

Go to the CE Journal

Discover more on our blog

Our blog contains the latest news and updates from the Conservation Evidence team, the Conservation Evidence Journal, and our global partners in evidence-based conservation.


Who uses Conservation Evidence?

Meet some of the evidence champions

Endangered Landscape Programme Red List Champion - Arc Kent Wildlife Trust The Rufford Foundation Save the Frogs - Ghana Bern wood Supporting Conservation Leaders National Biodiversity Network Sustainability Dashboard Frog Life The international journey of Conservation - Oryx British trust for ornithology Cool Farm Alliance UNEP AWFA Butterfly Conservation People trust for endangered species Vincet Wildlife Trust