The Hungarian birch mouse (''Sicista trizona'') is a species of

birch mouse Birch mice (genus ''Sicista'') are small jumping rodents that resemble mice with long, tufted tails and very long hind legs, allowing for remarkable leaps. They are the only extant members of the family Sminthidae. They are native to Eurasian for ...

in the family

Sminthidae Sminthidae is a family of mouse-like jumping rodents. They are represented by only one extant genus, ''Sicista'', represented by 19 species found throughout most of Eurasia, from central Europe east to Siberia, and south to southern China. However, ...

. It was once found throughout

Central Europe Central Europe is an area of Europe between Western Europe and Eastern Europe, based on a common historical, social and cultural identity. The Thirty Years' War (1618–1648) between Catholicism and Protestantism significantly shaped the area' ...

and

Romania Romania ( ; ro, România ) is a country located at the crossroads of Central Europe, Central, Eastern Europe, Eastern, and Southeast Europe, Southeastern Europe. It borders Bulgaria to the south, Ukraine to the north, Hungary to the west, S ...

, but is now only known from two isolated populations in

Hungary Hungary ( hu, Magyarország ) is a landlocked country in Central Europe. Spanning of the Carpathian Basin, it is bordered by Slovakia to the north, Ukraine to the northeast, Romania to the east and southeast, Serbia to the south, Croatia a ...

and

Transylvania Transylvania ( ro, Ardeal or ; hu, Erdély; german: Siebenbürgen) is a historical and cultural region in Central Europe, encompassing central Romania. To the east and south its natural border is the Carpathian Mountains, and to the west the Ap ...

in Romania, each of which belong to their own

subspecies In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...

Taxonomy

It was long thought to be a subspecies of the

southern birch mouse The southern birch mouse (''Sicista subtilis'') is a species of birch mouse in the family Sminthidae. It is native to southern Russia, Kazakhstan, and potentially northern Mongolia and China. Taxonomy The Hungarian birch mouse (''S. trizona'' ...

(''S. subtilis''), but a 2016 study found sufficient genetic and anatomical divergence for it to be considered its own species. The same study found the Romanian population of the species to have enough genetic divergence from the Hungarian population to be described as its own subspecies, the Transylvanian birch mouse (''S. t. transylvanica'').

Distribution

The Hungarian birch mouse was formerly found throughout the

Pannonian Basin The Pannonian Basin, or Carpathian Basin, is a large Sedimentary basin, basin situated in south-east Central Europe. The Geomorphology, geomorphological term Pannonian Plain is more widely used for roughly the same region though with a somewh ...

, including most of Hungary,

Austria Austria, , bar, Östareich officially the Republic of Austria, is a country in the southern part of Central Europe, lying in the Eastern Alps. It is a federation of nine states, one of which is the capital, Vienna, the most populous ...

Slovakia Slovakia (; sk, Slovensko ), officially the Slovak Republic ( sk, Slovenská republika, links=no ), is a landlocked country in Central Europe. It is bordered by Poland to the north, Ukraine to the east, Hungary to the south, Austria to the s ...

, and

Serbia Serbia (, ; Serbian language, Serbian: , , ), officially the Republic of Serbia (Serbian language, Serbian: , , ), is a landlocked country in Southeast Europe, Southeastern and Central Europe, situated at the crossroads of the Pannonian Bas ...

. It is now thought to be

extirpated Local extinction, also known as extirpation, refers to a species (or other taxon) of plant or animal that ceases to exist in a chosen geographic area of study, though it still exists elsewhere. Local extinctions are contrasted with global extinct ...

from Austria and is likely also extirpated from Slovakia and Serbia. Based on records, it was likely abundant in Hungary prior to 1950, but it is now restricted to the Borsodi Mezőség Protected Landscape Area. The Transylvanian birch mouse was likely found throughout the

Transylvanian Plateau The Transylvanian Plateau ( ro, Podișul Transilvaniei; hu, Erdélyi-medence) is a plateau in central Romania. The plateau lies within and takes its name from the historical region of Transylvania, and is almost entirely surrounded by the Easte ...

in the past, but its range has likely shrunk due to agriculture. It is known only from several locations in

Cluj County Cluj County (; german: Kreis Klausenburg, hu, Kolozs megye) is a county ( județ) of Romania, in Transylvania. Its seat ( ro, Oraș reședință de județ) is Cluj-Napoca (german: Klausenburg). Name In Hungarian, it is known as ''Kolozs megye ...

. Its full range has not yet been fully established.

Habitat and ecology

This species depends on undisturbed

grassland A grassland is an area where the vegetation is dominated by grasses (Poaceae). However, sedge (Cyperaceae) and rush (Juncaceae) can also be found along with variable proportions of legumes, like clover, and other herbs. Grasslands occur natur ...

habitat or grassland grazed by livestock, which has become rare due to

mechanized agriculture Mechanised agriculture or agricultural mechanization is the use of machinery and equipment, ranging from simple and basic hand tools to more sophisticated, motorized equipment and machinery, to perform agricultural operations. In modern times, po ...

. The Hungarian subspecies is most abundant in remnant patches of tall vegetation such as

thistle Thistle is the common name of a group of flowering plants characterised by leaves with sharp prickles on the margins, mostly in the family Asteraceae. Prickles can also occur all over the planton the stem and on the flat parts of the leaves. ...

pasture Pasture (from the Latin ''pastus'', past participle of ''pascere'', "to feed") is land used for grazing. Pasture lands in the narrow sense are enclosed tracts of farmland, grazed by domesticated livestock, such as horses, cattle, sheep, or swine ...

s that are otherwise grazed by livestock. It is also known from saline

fescue ''Festuca'' (fescue) is a genus of flowering plants belonging to the grass family Poaceae (subfamily Pooideae). They are evergreen or herbaceous perennial tufted grasses with a height range of and a cosmopolitan distribution, occurring on every ...

meadow A meadow ( ) is an open habitat, or field, vegetated by grasses, herbs, and other non-woody plants. Trees or shrubs may sparsely populate meadows, as long as these areas maintain an open character. Meadows may be naturally occurring or artifi ...

s, wormwood-fescue

steppe In physical geography, a steppe () is an ecoregion characterized by grassland plains without trees apart from those near rivers and lakes. Steppe biomes may include: * the montane grasslands and shrublands biome * the temperate grasslands, ...

s, and abandoned agricultural fields at lower densities. The Transylvanian subspecies is known from slopes that are highly encroached upon by

shrub A shrub (often also called a bush) is a small-to-medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. Shrubs can be either deciduous or evergreen. They are distinguished from trees ...

s, also in areas otherwise used for livestock grazing.

Conservation

''S. trizona'' is one of the rarest and least known small

mammal Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fur or ...

species in

Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a Continent#Subcontinents, subcontinent of Eurasia ...

. The Hungarian subspecies has been extirpated from most of its range due to mechanized agriculture allowing for larger areas to be mowed at once, which reduces the diversity of plant species and makes the habitat unsuitable for the birch mice. Although some areas have been set aside for the protection of the species, this protected area is relatively small and the surrounding area is still mechanically cut or overgrazed. The Transylvanian birch mouse is also threatened by intensive agriculture as well as

overgrazing Overgrazing occurs when plants are exposed to intensive grazing for extended periods of time, or without sufficient recovery periods. It can be caused by either livestock in poorly managed agricultural applications, game reserves, or nature res ...

sheep Sheep or domestic sheep (''Ovis aries'') are domesticated, ruminant mammals typically kept as livestock. Although the term ''sheep'' can apply to other species in the genus ''Ovis'', in everyday usage it almost always refers to domesticated s ...

. Both populations that were later classified into this species were feared to be

extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...

throughout much of the 20th century until being rediscovered the 21st century; the Hungarian subspecies was not seen for over 70 years until being rediscovered in 2006, while the Transylvanian subspecies was only rediscovered in 2014. These threats and rarity have led to the species being classified as

Endangered An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching and inva ...

on the

IUCN Red List The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is the world's most comprehensive inventory of the global conservation status of biol ...

References

{{Taxonbar, from=Q64876009 Sicista Fauna of Hungary Fauna of Romania Endangered biota of Europe Mammals described in 1865 Taxa named by Imre Frivaldszky