Tiny Taiwanese Frog Uses Concrete Drain to Boost Mating Calls

The Mientien tree frog is about 2 to 4 centimeters in size and unique to Taiwan.

A research team from National Taiwan University has found that a tiny frog unique to Taiwan uses concrete drains as a medium to amplify its call during mating season. The discovery has received ample media attention since it was published in Journal of Zoology on 4 June this year.

The Mientien tree frogs (Kurixalus idiootocus ), whose mating season occurs between February and October each year, are only about 2 to 4 centimeters in size and are often found around mountainous foothills in suburban areas. To these tiny frogs, the concrete drains in urban Taipei serve as miniature canyons that help augment their mating calls. Students Wen-Hao Tan (譚文皓) and Chieh Lin (林杰) of the Department of Life Sciences initially discovered that male Mientien tree frogs had the tendency to congregate in the drains during mating season, therefore a hypothesis relating the behavior to their favored location was established.

With the assistance of Department of Life Sciences Professor Yu-Teh Kirk Lin (林雨德) and Graduate Institute of Musicology Professor Chen-Gia Tsai (蔡振家), the team came to the conclusion that the frogs preferentially called inside the drains, as opposed to outside, as their cries were enhanced in terms of amplitude and duration. The team also pointed out that besides serving as an acoustic booster; it is also possible that the drains were chosen for reasons such as protection from natural enemies. It added, however, that the drains were not able to boost sound properties.

As to whether this unique behavior enhances their chances for mating, the team stated that more research still needs to be done.

The research entitled “Urban Canyon Effect: Storm Drains Enhance Call Characteristics of the Mientien Tree Frog,” is the first to report that a wild animal uses human structures to enhance acoustics for mating. The report has been widely covered by the international media, including Nature, Science Daily, Live Science, Discovery News, Yahoo! News, and Phys Org.

For the in depth report, read the full report published in Journal of Zoology HERE.