Artificial incubation of yellow-headed sideneck turtle Podocnemis unifilis eggs to reduce losses to flooding and predation, Cojedes and Manapire Rivers, southern Venezuela
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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.
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.
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Relocate nests/eggs to a hatchery: Tortoises, terrapins, side-necked & softshell turtles Action Link |
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Relocate nests/eggs for artificial incubation: Tortoises, terrapins, side-necked & softshell turtles Action Link |
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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)
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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)
