Experimental evaluation of captive-rearing practices to improve success of snake reintroductions

  • Published source details Roe J.H., Frank M.R. & Kingsbury B.A. (2015) Experimental evaluation of captive-rearing practices to improve success of snake reintroductions. Herpetological Conservation and Biology, 10, 711-722.


This study is summarised as evidence for the following.

Action Category

Head-start wild-caught reptiles for release: Snakes & lizards

Action Link
Reptile Conservation
  1. Head-start wild-caught reptiles for release: Snakes & lizards

    A replicated, randomized, controlled study in 2007–2010 in mixed wetland, shrubland and hardwood forest in Indiana, USA (Roe et al. 2015) found that common water snakes Nerodia sipedon sipedon that were released following two methods of head-starting had similar survival rates and showed similar behaviour compared to resident snakes, but grew more slowly. Annual survival following release was similar for head-started snakes (basic conditions: 64%, semi-natural conditions: 50%) and resident snakes (46%). A range of behaviour and activity measures, including post-release movement, habitat use, and hibernation date were also similar between head-started and resident snakes (see paper for details). Head-started snakes grew more slowly than resident snakes (head-started: 0–0.05 cm/day; resident: 0–0.11 cm/day), but body condition remained similar between all groups (data presented as statistical model result). In July 2007, seven pregnant female snakes were captured and brought into captivity. Sixty offspring were raised for 18 months in individual plastic tubs (20 x 64 x 13 cm) containing a water bowl and hide. In February 2009, snakes were divided in to two groups and raised for a further four months in either basic conditions (remaining in the plastic tub) or semi-natural conditions (see paper for details). After 22 months in captivity, head-started snakes (basic conditions: 12 snakes; semi-natural conditions: 10 snakes) and an additional 15 resident wild snakes were released, and radio-tracked 1–4 times/month throughout the year. Of the resident snakes, eight were tracked in 2008–2009, three in 2009–2010, and four during both seasons.

    (Summarised by: William Morgan)

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 21

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 ProgrammeRed List Champion - Arc Kent Wildlife Trust The Rufford Foundation Save the Frogs - Ghana Mauritian Wildlife Supporting Conservation Leaders
Sustainability Dashboard National Biodiversity Network Frog Life The international journey of Conservation - Oryx Cool Farm Alliance UNEP AWFA Bat Conservation InternationalPeople trust for endangered species Vincet Wildlife Trust