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Evaluating the effect of overharvesting on genetic diversity and genetic population structure of the coconut crab.

ABSTRACT: Birgus latro (coconut crab) is an edible crustacean that has experienced serious overharvesting throughout its whole habitat range; however, the negative effects of overharvesting on the genetic diversity within B. latro populations have not been elucidated. Here, we report sex ratio, body size, and genetic diversity in populations of B. latro in the Ryukyu Islands where large-male-biased overharvesting of B. latro has continued. In 2 of the study populations, the sex ratio was significantly skewed toward females, and in all of the study populations large males were rare, which we attributed to sex- and size-biased overharvesting. We found no differences in genetic diversity between small and large individuals, suggesting that genetic diversity, even among the large (i.e., old) individuals, may have had already been negatively affected by overharvesting. Continued monitoring of sex ratio, body size and genetic diversity are needed for effective management of the study populations.

SUBMITTER: Yorisue T

PROVIDER: S-EPMC7308380 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Evaluating the effect of overharvesting on genetic diversity and genetic population structure of the coconut crab.

Yorisue Takefumi T Iguchi Akira A Yasuda Nina N Yoshioka Yuki Y Sato Taku T Fujita Yoshihisa Y

Scientific reports 20200622 1

Birgus latro (coconut crab) is an edible crustacean that has experienced serious overharvesting throughout its whole habitat range; however, the negative effects of overharvesting on the genetic diversity within B. latro populations have not been elucidated. Here, we report sex ratio, body size, and genetic diversity in populations of B. latro in the Ryukyu Islands where large-male-biased overharvesting of B. latro has continued. In 2 of the study populations, the sex ratio was significantly ske ...[more]

PMID: 32572270

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Dataset Information

Evaluating the effect of overharvesting on genetic diversity and genetic population structure of the coconut crab.

Publications

Evaluating the effect of overharvesting on genetic diversity and genetic population structure of the coconut crab.

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