Genetic structure of a Japanese brown frog (Rana japonica) population implies severe restriction of gene flow caused by recent urbanization in a satoyama landscape

Abstract

Rapid urbanization is one of the major pressures on amphibian species. Elucidating changes in genetic structure will be useful in evaluating the effects of urbanization on amphibian populations. Our study focused on Rana japonica, which is common in complex agricultural landscapes known as satoyama, which are also under intense development pressure. We conducted landscape genetic analyses based on mitochondrial DNA haplotype frequencies of 13 breeding sites in a rapidly urbanizing area of Japan. We found several breeding sites had significantly higher F _st values, and we also identified the barriers to gene flow between these sites. Observation of past aerial photographs revealed that these barriers coincided with the construction of man-made structures in the last few decades, suggesting that urbanization has restricted gene flow in R. japonica. Our results show that landscape genetic approaches are useful in conservation planning where rapid habitat degradation has taken place.

Keywords::

• Genetic structure
• urbanization
• landscape genetics
• gene flow
• Rana japonica

Acknowledgements

We would like to thank our laboratory members and technical staffs for help in sampling and technical assistance. We would also like to specially thank Wataru Kitamura and Motoshi Tomita for comments and advice on the analyses.

Declaration of interest : The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.