Study

Pivotal temperature for green sea turtles, Chelonia mydas, nesting in suriname

  • Published source details Godfrey M.H. & Mrosovsky N. (2006) Pivotal temperature for green sea turtles, Chelonia mydas, nesting in suriname. The Herpetological Journal, 16, 55-61.

Actions

This study is summarised as evidence for the following.

Action Category

Alter incubation temperatures to achieve optimal/desired sex ratio: Sea turtles

Action Link
Reptile Conservation
  1. Alter incubation temperatures to achieve optimal/desired sex ratio: Sea turtles

    A replicated study in 1995 in an artificial setting in Toronto, Canada (Godfrey & Mrosovsky 2006) found that more female green turtle Chelonia mydas hatchlings were produced at higher incubation temperatures compared to at lower temperatures. Hatching success for two clutches of eggs was 8% (7 of 90 eggs) and 62% (67 of 108 eggs). Warmer incubation temperatures produced a higher proportion of female hatchings (30.6°C: 100%; 30.0°C: 50%; 29.4°C: 47%; 28.7°C: 36%; 28.4°C: 18%; 28.2°C: 8%; 27.6°C: 0%). The pivotal temperature for determining sex of hatchlings was estimated at 29.4–30°C. In 1995, green turtle eggs were collected from two nests (90 from one nest and 108 from a second) and brought into an artificial setting and placed in an individual container on a sponge with damp vermiculite. Eggs were incubated at one of seven temperatures between 27.6°C to 30.6°C (14–48 eggs/temperature). Hatching success was assessed, and sex of hatchlings was determined by examining the gonads under a microscope.

    (Summarised by: William Morgan)

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