Study

Wild versus head-started hawksbill turtles Eretmochelys imbricata: post-release behavior and feeding adaptions

  • Published source details Okuyama J., Shimizu T., Abe O., Yoseda K. & Arai N. (2010) Wild versus head-started hawksbill turtles Eretmochelys imbricata: post-release behavior and feeding adaptions. Endangered Species Research, 10, 181-190.

Actions

This study is summarised as evidence for the following.

Action Category

Translocate adult or juvenile reptiles: Sea turtles

Action Link
Reptile Conservation

Head-start wild-caught reptiles for release: Sea turtles

Action Link
Reptile Conservation
  1. Translocate adult or juvenile reptiles: Sea turtles

    A study in 2005–2006 off the coast of an island in southwestern Japan (Okuyama et al. 2010) found that translocated hawksbill turtles Eretmochelys imbricata that were held in captivity before release tended to return to their point of capture. Five wild-caught turtles (held in captivity for 4 months) were tracked for 2–8 days, and two were recaptured 182–199 days after release at their original point of capture (around 5–15 km from release site). An additional four head-started turtles were tracked for 4–9 days and a fifth turtle was tracked intermittently for 10 months. Five wild turtles were captured and held in captivity for four months in large rearing tanks (2 or 5 kl). Five head-started turtles were raised for 2.5 years after being hatched from eggs collected on the island. All turtles were fitted with radio transmitters and released in April 2005 following 1 h sea-acclimation in an enclosure net (4 × 4 × 5 m). Turtles were tracked using 12 fixed receivers deployed on the ocean floor (18 m deep).

    (Summarised by: Maggie Watson, William Morgan)

  2. Head-start wild-caught reptiles for release: Sea turtles

    A controlled study in 2005–2006 off the coast of an island in southwestern Japan (Okuyama et al. 2010) found that released head-started hawksbill turtles Eretmochelys imricata were tracked for several days after release. Four head-started turtles were tracked for 4–9 days, and a fifth turtle was tracked intermittently for 10 months. An additional five wild-caught turtles (held in captivity for 4 months) were tracked for 2–8 days, and two were recaptured 182–199 days after release. Head-started turtles either moved in random directions (four turtles) or stayed at the release site (one turtle), and wild-caught turtles tended to return to their original points of capture. Turtle eggs were collected from a nesting beach on the island and artificially incubated (29°C; >90% humidity), and hatchlings were reared for 2.5 years. An additional five wild turtles were captured and held in captivity for four months. All turtles were fitted with radio transmitters and released in April 2005 following 1 h sea-acclimation in an enclosure net (4 × 4 × 5 m). Turtles were tracked using 12 fixed receivers deployed on the ocean floor (18 m deep).

    (Summarised by: Maggie Watson, William Morgan)

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