AmphibiaChina 中国两栖类.

Description
Very similar to the Common Tree Frog (Hyla arborea), but differs from it by usually having a dark spot on the upper lip below the eye, lack of an inguinal loop, and slightly shorter hind legs (when the hind leg is stretched along the body, the tibio-tarsal articulation commonly reaches the posterior edge of the eye). Tympanic membrane smaller than eye. Dorsal skin smooth, ventral skin granular. Coloration and sexual dimorphism are similar to those in the Common Tree Frog (the main difference is the absence of the inguinal loop). Dark lateral band regularly disrupted into spots and partially reduced. The tips of fingers and toes have round adhesive discs. The forelimb webbing is poorly developed. The mean snout-vent length for males is 31 mm (range 26-45 mm) and for females is 35 mm (range 26-41 mm). The nuptial pads in males are yellow.

Distribution and Habitat

Country distribution from AmphibiaWeb's database: China, Japan, Korea, Democratic People's Republic of, Korea, Republic of, Mongolia, Russian Federation

View distribution map in BerkeleyMapper.

The species is widespread in Japan, Korea, China (Fujian, Hunan, Jiangxi, Zhejiang, Jiangsu, Anhui, Hubei, Guizhou, Sichuan, Shaanxi, Henan, Hebei, Liaoning, Jilin and Heilongjiang provinces, as well as Inner Mongolia Autonomous Region), Northern Mongolia, the Russian Far East (the valleys of the Amur and Ussuri Rivers and their tributaries) and south to Lake Baikal (northernmost record, in a warm hollow of the Barguzin River valley: ca. 54º30'N, 110ºE). The species inhabits mixed and deciduous broad-leafed forests, bushlands, forest steppes, meadows and swamps. In forestless areas, the tree frog primarily inhabits river valleys with shrubs. It also occurs in settlements, even in several large cities. Spawning occurs in stagnant ponds, puddles, oxbow lakes, flooded quarries and lakes with dense herbaceous vegetation. The eggs are sometimes deposited in river and stream pools.

Life History, Abundance, Activity, and Special Behaviors
This tree frog is a common, sometimes abundant amphibian, except in the northern parts of its range. The overall population density probably decreases from the south to the north, e.g. from the southern to the northern part of the Amurland. Hibernation probably occurs from September-October to April - May (sometimes June) on land, with individuals taking refuge in leaf litter, rodent burrows, holes in trees, under stones, etc. Reproduction occurs later than in many other syntopic amphibians, in May - August, in relatively warm water. Males enter ponds earlier than females. They call in a similar manner to the Common Tree Frog (Hyla arborea). The mating call has notes lasting 0.1-0.2 seconds at an interval of 0.2-0.5 seconds. The fundamental frequency is 1.7 kHz, with clear harmonics. Breeding choruses occur not only at night but also during the day.

An and Waldman (2016) found that Hyla japonica males with natural infections of Batrachochytrium dendrobatidis called longer and made more rapid calls than did uninfected males. This may have two effects, which are possibly interrelated. Because female frogs are generally attracted to males that call longer and faster, pathogen transmission might be enhanced. Alternatively, the altered calls might result from selection on males for early reproductive success in anticipation of a premature death. However, it is unknown whether Japanese tree frog females actually prefer infected males.

The clutch contains about 340-1500 eggs deposited singly or in a few clumps of 7-100 eggs. Females deposit their eggs both by day and night. Recently deposited spawn usually floats on the water surface. Some eggs are deposited on submerged plants. Metamorphosis occurs in summer or autumn; in some cases the tadpoles hibernate. Sexual maturity is attained probably in the 3rd-4th year of life. The majority of adults are 4-6 years old, but the maximum longevity is estimated as 6-11 years.

Newly metamorphosed froglets prey upon Aphidinea and Cicadodea, whereas adult frogs feed on spiders and various insects. Active foraging occurs at twilight; during the day, frogs catch only the insects which approach them. This species feeds on spiders, Diptera, Hymenoptera, Coleoptera, and larval Lepidoptera.

Trends and Threats
The Japanese Tree Frog seems not to be declining throughout its range, except for some peripheral northern populations.

Relation to Humans
The species often occurs in agricultural lands, in settlements and cities. However, the influence of anthropogenic factors on it remains unstudied.

Comments
Karotype: Diploid chromosome (2n) with 6 large pairs and 6 small ones making a total of 24 chromosomes.

Read more about The Amphibians of Mongolia by Kuzman 2017 (PDF)

References

An, Deuknam, and Waldman, Bruce (2016). ''Enhanced call effort in Japanese tree frogs infected by amphibian chytrid fungus.'' Biology Letters, 12(3).

Bannikov, A. G., Darevsky, I. S. and Rustamov, A. K. (1971). Zemnovodnye i Presmykayushchienya SSSR [Amphibians and Reptiles of the USSR]. Izdatelistvo Misl, Moscow.

Bannikov, A. G., Darevsky, I. S., Ishchenko, V. G., Rustamov, A. K., and Szczerbak, N. N. (1977). Opredelitel Zemnovodnykh i Presmykayushchikhsya Fauny SSSR [Guide to Amphibians and Reptiles of the USSR Fauna]. Prosveshchenie, Moscow.

Fei, L. (1999). Atlas of Amphibians of China. Henan Publishing House of Science and Technology, Zhengzhou.

Kuzmin, S. L. (1995). Die Amphibien Russlands und angrenzender Gebiete. Westarp Wissenschaften, Magdeburg.

Kuzmin, S. L. (1999). The Amphibians of the Former Soviet Union. Pensoft, Sofia-Moscow.

Maeda, N. and Matsui, M. (1990). Frogs and Toads of Japan, 2nd edition. Bun-Ichi Sogo Shuppan Co., Ltd., Tokyo, Japan.

Nikolsky, A. M (1936). Fauna of Russia and Adjacent Countries: Amphibians (English translation of Nikolsky, 1918, Faune de la Russie et des Pays limitrophes. Amphibiens. Académie Russe des Sciences, Petrograd, USSR). Israel Program for Scientific Translations, Jerusalem.

Stejneger, L. H. (1907). Herpetology of Japan and Adjacent Territory, United States National Museum Bulletin 58. Smithsonian Institution, Washington, D. C..

Terent'ev, P. V. and Chernov, S. A (1965). Key to Amphibians and Reptiles [of the USSR]. Israel Program for Scientific Translations, Jerusalem.

Vorobyeva, E. I. and Darevsky, I. S. (eds.) (1988). Amphibians and Reptiles of Mongolian People's Republic: General Problems. Amphibians.. Moscow.

Won, H.-K. (1971). Choson Ryangso Pyachyungryuchji [Amphibian and Reptilian Fauna of Korea]. Korean Academy of Sciences, Pyongyang.

Ye, C., Fei, L., and Hu, S. Q. (1993). Rare and Economic Amphibians of China. Sichuan Publishing House of Science and Technology, Chengdu.

Zhao, E. and Adler, K. (1993). Herpetology of China. Society for the Study of Amphibians and Reptiles, Oxford, Ohio.

Zhao, E. and Zhao, H. (1994). Chinese Herpetological Literature: Catalogue and Indices. Chengdu University of Science and Technology, Chengdu.

Species Account Citation: AmphibiaWeb 2017 Hyla japonica: Japanese Tree Frog <https://amphibiaweb.org/species/832> University of California, Berkeley, CA, USA. Accessed Jan 27, 2025.

Citation: AmphibiaWeb. 2025. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 27 Jan 2025.

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