Study

Demography and movement in a relocated population of Oregon spotted frogs (Rana pretiosa): influence of season and gender

  • Published source details Chelgren N.D., Pearl C.A., Adams M.J. & Bowerman J. (2008) Demography and movement in a relocated population of Oregon spotted frogs (Rana pretiosa): influence of season and gender. Copeia, 2008, 742-751.

Actions

This study is summarised as evidence for the following.

Action Category

Create ponds for frogs

Action Link
Amphibian Conservation

Translocate frogs

Action Link
Amphibian Conservation
  1. Create ponds for frogs

    A replicated study in 2001–2004 in four created ponds within a wetland in Oregon, USA (Chelgren et al. 2008) found that survival of translocated Oregon spotted frogs Rana pretiosa increased with increasing pond age. Nine ponds were created in 2001–2004 using explosives (0.01–0.07 ha; 2 m deep). In spring 2001, nine spotted frog egg masses and in June–September 2001, 41 frogs were translocated to the four largest ponds from a site 2.5 km away. Frogs were tagged.

     

  2. Translocate frogs

    A study in 2001–2004 of created ponds within a wetland in Oregon, USA (Chelgren et al. 2008) found that survival was lower for Oregon spotted frogs Rana pretiosa translocated as adults compared to those translocated as eggs. Frogs had a significantly lower survival rate during the first year after translocation, compared to the following three years (e.g. large frogs: 28–44% vs 48–74%) and non-relocated frogs. Annual survival rate was significantly higher for large frogs (>53 mm; 48–74%) compared to small frogs (40–53 mm; 5–39%). Survival increased with increasing pond age. Nine ponds were created in 2001–2004 using explosives (0.01–0.07 ha; 2 m deep). In spring 2001, nine spotted frog egg masses and in June–September 2001, 41 marked frogs were translocated to the four largest ponds, from a site 2.5 km away.

     

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 18

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