New method of estimating sex proportion in sea turtle hatchlings using temperature data in hatcheries
DOI:
https://doi.org/10.33064/iycuaa2020802998Keywords:
nest temperature, sex ratio in hatchlings, sea turtle, sex determination, Lepidochelys olivaceaAbstract
The incubation temperature of sea turtle eggs determines the sex of the offspring. In recent years a bias towards females has been documented, so an easy and practical mathematical model was developed in MATLAB that uses the Girondot equation to estimate the proportion of males in a clutch. The program takes as input Excel files containing daily temperature records from the hatchery measured with a digital sensor similar to that of the proposed study, and laying date, hatching date, and number of eggs or live offspring from the nesting log. This model can be applied to different species of sea turtles and nesting beaches. A case study is presented for Lepidochelys olivacea (olive ridley turtle) at Playa Ceuta turtle rookery located in Sinaloa, Mexico.
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