Sākums Animals Eastern Tree Frog

Eastern Tree Frog

Eastern Tree Frog occurs in eastern and central parts of Europe, the range also extends into the extreme western part of Asia.

The countries of occurrence include Armenia, Azerbaijan, Belarus, Bulgaria, Georgia, Greece, Iran, Latvia, Lithuania, Moldova, Poland, Romania, Russia (South European part), Serbia, Turkey and Ukraine.

Due to ongoing decline in the extent and quality of its habitat, the population is inferred to be decreasing. Agricultural pollution from pesticides is a major threat.


■ Listed in Appendix II of the Bern Convention on the Conservation of European Wildlife and Natural Habitats as a strictly protected fauna species.
■ Listed in Annex IV of EU Council Directive 92/43/EEC on the Conservation of natural habitats of wild fauna and flora (the Habitats Directive).
■ An especially protected species in Latvia (the Cabinet of Ministers’ Regulations No. 396 on November 14, 2000).

Reintroduction of Eastern Tree Frog in Latvia

Riga Zoo’ most significant contribution to biodiversity conservation in Latvia is the successful reintroduction of the Eastern Tree Frog (Hyla orientalis). In 1988–1992, a total of 4110 Tree Frog young, bred in the Zoo’s Laboratory of Ecology, were released into the wild in Blažģa Ezers protected nature area. As a result, a healthy wild Eastern Tree Frog population was established in Southwestern Latvia. The reintroduction project was initiated and led by Juris Zvirgzds, Head of the Zoo’s Laboratory of Ecology. In 1997, Juris Zvirgzds received the award of the Cabinet of Ministers of the Republic of Latvia for his contribution to nature protection and conservation of biodiversity.


Zvirgzds J., Stašuls M., Vilnītis V. 1995. Reintroduction of the European Tree Frog (Hyla arboreain Latvia. – Memoranda Soc. Fauna Flora Fennica 71: 139–142.

Zvirgzds J. 2002. Kokvardes reintrodukcija Latvijā (The reintroduction to Latvia of European Tree Frogs (Hyla arborea Linnaeus, 1758)). – Rīgas Nacionālais zooloģiskais dārzs 2001. gadā. 54.–58. lpp. (In Latvian, with English summary.)

Звиргздс Ю., Хрщенович Э. 2008. Pеинтродукция квакши в Латвии (Reintroduction of the Tree Frog in Latvia). Презентация в семинаре (PPT presentation, in Russian).

Dunce I. 2013. Re-introduction of European tree frog in Latvia. – Pp. 33–36 in Soorae P.S. (ed.) Global Re-introduction Perspectives: 2013. Further case studies from around the globe. Gland, Switzerland: IUCN/SSC Re-introduction Specialist Group and Abu Dhabi, UAE: Environment Agency-Abu Dhabi.

Gulbe E., Di Marzio A. 2020. Kokvaržu populācija Latvijā 30 gadus pēc reintrodukcijas (Tree Frog population in Latvia 30 years after reintroduction). – Rīgas Nacionālais zooloģiskais dārzs 2019. 51.–55. lpp. (In Latvian and English.)

Birbele E., Di Marzio A., Deksne G. 2022. Species identification of the reintroduced Hyla Treefrog: preliminary results. Abstract. – University of Latvia: 80th Scientific conference, Zoology and Animal Ecology sub-section. Abstract Book. 3 February 2022, Nature House, University of Latvia, Riga, Latvia. P. 16.


■ Phylum Chordata – chordates
■ Class Amphibia – amphibians
■ Order Anura – frogs
■ Family Hylidae – tree frogs and their allies
■ Species Hyla orientalis – Eastern Tree Frog

European Tree Frog (Hyla arborea) that formerly was regarded as a polytypic species in 2008 was divided into several, quite similar new species. According to this approach, the tree frog populations of Eastern Europe and also Latvia, belong to Hyla orientalis.

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