Frog of the Week

Japanese Common Toad (Bufo japonicus)

Japanese Common Toad
photo by Yasunori Koide 

Common Name: Japanese Common Toad
Scientific Name: Bufo japonicus
Family: Bufonidae – True Toad family
Locations: Japan
Size: 3.1 – 6.9 inches (80 – 176 mm)

The Japanese Common Toad lives on the islands of Kyusyu, Shikoku, Hokkaido, and Honshu of Japan. They have also been introduced to the island of Izu Oshima. Additionally, they live in a wide range of habitats from coastal areas to high in the mountains. The toads vary in color from a dark green, yellowish brown, to dark brown. Like most toads, they are active during the night and hide during the day.

Two subspecies of the toads are recognized by some researchers. The subspecies are the Eastern Japanese Common Toad (Bufo japonicus formosus) and the Western Japanese Common Toad (Bufo japonicus japonicus). The western subspecies is slightly larger than the eastern.

Mating

The breeding season for the toads is late winter / early spring from February to March. The toads migrate to ponds and swamps to breed. They use odor cues to find their way to these water bodies. In the pond, the males outnumber the females, leading to fighting and scrambling for a mate. The males try to grasp the females from behind in the amplexus position. Next, the female starts to lay her eggs. The females lay between 1,500-14,000 eggs. Then, the male fertilizes the eggs. Neither parent provides any care for their offspring. The eggs hatch into tadpoles shortly after. Then, the tadpoles complete their metamorphosis in June.

Conservation for the Japanese Common Toad

The International Union for the Conservation of Nature (IUCN) Red List categorizes the Japanese Common Toad as Least Concern for Extinction. The species populations are decreasing but not at an alarming rate. The main cause of the declines is habitat loss from the urbanization of their land.