Study

Artificial incubation of yellow-headed sideneck turtle Podocnemis unifilis eggs to reduce losses to flooding and predation, Cojedes and Manapire Rivers, southern Venezuela

  • Published source details Herández O., Espinosa-Blanco A.S., May Lugo C., Jimenez-Oraa M. & Seijas A.E. (2010) Artificial incubation of yellow-headed sideneck turtle Podocnemis unifilis eggs to reduce losses to flooding and predation, Cojedes and Manapire Rivers, southern Venezuela. Conservation Evidence, 7, 100-105.

Actions

This study is summarised as evidence for the following.

Action Category

Relocate nests/eggs to a hatchery: Tortoises, terrapins, side-necked & softshell turtles

Action Link
Reptile Conservation

Relocate nests/eggs for artificial incubation: Tortoises, terrapins, side-necked & softshell turtles

Action Link
Reptile Conservation
  1. Relocate nests/eggs to a hatchery: Tortoises, terrapins, side-necked & softshell turtles

    A replicated, controlled study in 2009 on two rivers in Southern Venezuela (Herández et al. 2010) found that relocating eggs of yellow-headed sideneck turtles Podocnemis unifilis to a hatchery resulted in higher hatching success compared to eggs from natural nests and eggs incubated artificially. Results were not statistically tested. Hatching success was higher for eggs from the hatchery (88%) than for eggs from both natural nests (63%) and artificially incubated eggs (42%). Five eggs each from 27 nests (136 total) at one river were moved to a hatchery and reburied in a trench (200 x 40 x 30 cm) using sand from the nesting site. The area was protected by a 1.5 m metal mesh fence, and two staff monitored the site and poured 5 litres of water over the trench each week. All eggs from 13 nests (401 total) at the second river were placed in sand-filled polystyrene containers and incubated indoors in ambient conditions. All eggs from a further 51 nests from the first river were left in place. In February 2009, a 6 km and 13 km stretch of each river was searched for nests. In May, these locations were revisited to assess hatching success.

    (Summarised by: William Morgan)

  2. Relocate nests/eggs for artificial incubation: Tortoises, terrapins, side-necked & softshell turtles

    A replicated, controlled study in 2009 on two rivers in Southern Venezuela (Herández et al. 2010) found that artificially incubating eggs of yellow-headed sideneck turtles Podocnemis unifilis resulted in lower hatching success compared to eggs moved to an on-beach hatchery and eggs from natural nests. Results were not statistically tested. Hatching success was lower for artificially incubated eggs (42%) than for eggs from both the on-beach hatchery (88%) and natural nests (63%). Eggs that were artificially incubated came from locations where all eggs from a further 74 nests had been harvested by people. All eggs from 13 nests (401 total) at one river were placed in sand-filled polystyrene containers and incubated indoors in ambient conditions. Five eggs each from 27 nests (136 total) at the second river were moved to a hatchery and reburied in a trench (200 x 40 x 30 cm) using sand from the nesting site. The area was protected by a 1.5 m metal mesh fence, and two staff monitored the site and poured 5 litres of water over the trench each week. All eggs from a further 51 nests from the second river were left in place. In February 2009, a six and 13 km stretch of each river was searched for nests. In May, these locations were revisited to assess hatching success

    (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 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