There are four ecoregions of Croatia that occur entirely or partly within the borders of Croatia:
- Pannonian Mixed Forests
- Dinaric Mountains mixed forests
- Illyrian deciduous forests
- Tyrrhenian-Adriatic sclerophyllous and mixed forests
This ecoregion consists of the depression surrounded by the Carpathian Mountains, Alps, and Dinaric Mountains. Avifauna diversity is high; there are fifty Important Bird Areas in this ecoregion. Lake Neusiedel with Seewinkel National Park, and other important wetlands are renowned for their birdlife (Heath and Evans 2000). Resident mammals are of the widespread throughout Europe including the European rabbit (Oryctolagus cuniculus), wolf (Canis lupus), and the endangered European mink (Mustela lutreola). There are a number of endangered reptiles including Orsini’s viper and Balkan wall lizard. Recreation and tourism, unsustainable exploitation, development and fragmentation, agricultural abandonment, and disturbance of wildlife, are other important threats (Heath & Evans 2000). There are a number of natural parks in this ecoregion, but much of the natural habitat has been lost to agriculture.
There are a total of 377 native vertebrates that have been recorded in the Pannonian mixed forests; however, a complete count of migratory birds and other occasional sightings swells this record to over 500 taxa. Moreover, none of these taxa are endemic due to the free migration of species among the Eurasian ecoregions, owing to ample large scale biological corridors in prehistoric times and to the landscape permeability of these ecoregions. Dominant canopy trees of the ecoregion include oak, poplar, beech and hornbeam.
The Dinaric Mountain range spans several countries of Eastern Europe and is covered by mixed forest with an outstanding variety of deciduous oak trees. These forests are among the largest and most continuous tracts of forested habitat remaining for large carnivores in Europe. The flora has a relatively high endemism rate with many relict and restricted range species. Faunal diversity is high, and a number of IBAs (Important Bird Areas) and threatened SPECs (Species of European Concern) are encompassed within the region. Human impact remains high in this ecoregion, mainly due to the socio-economic and political instability of most countries in the region, where illegal logging, illegal hunting, and uncontrolled plant harvesting have recently destroyed extensive forest areas that had remained virtually untouched until current times.
The mountain ranges of this region have had low human populations, and high canopy forests still prevail widely throughout. A significant number of pristine large forest stands remained quite untouched until very recently. Rapid and intense forest degradation in the form of illegal logging, pollution, and fire took place during the recent Balkan conflicts that led to the division of the Former Yugoslavia into a number of independent republics. Overexploitation of forests is ongoing in certain areas due to the political instability of most countries in the ecoregion.
The Illyrian deciduous forests extend all along the coastal ranges of the Eastern Adriatic coast, from the eastern Alps to the northern Ionian coast between Albania and Greece.
This ecoregion is actually comprised of three distinct forest types, two of which are broadleaf and one of which is a mixed conifer/broadleaf plant community. The region has a relatively high floral endemism rate with many relict and restricted range species. Faunal diversity is high, and a number of IBAs (Important Bird Areas) and threatened SPECs (Species of European Concern) are found within the region. Illegal logging, illegal hunting, and uncontrolled plant harvesting have destroyed extensive forest areas that have been relatively intact until recently.
Overexploitation of forests is ongoing in certain areas due to the political instability of most countries in the ecoregion. Additinally the coastal aspects of the region are a present attractant to the tourism industry, and significant amounts of tourism infrastructure and urbanisation are ongoing in the region from these drivers.
The Thyrrenian-Adriatic Sclerophyllous and Mixed Forests extend along the coastal lowlands of the southern half of the Italian Peninsula, Sicily, and Corsica. They include Sardinian Island and the Dalmatian Islands.
This ecoregion supports a rich diversity of flora and fauna. The floral endemism rate is high, and numerous relict and threatened plant species are found here. Two rare and endemic herbivore subspecies, mouflon (Ovis aries musimon) and Corsican red deer (Cervus elaphus corsicanus), persist on islands. A wide range of birds can be found here, including a number of endemic species, such as Marmora's warbler (Silvia sarda), and threatened raptors including Griffon vulture (Gyps fulvus), Eleonora’s falcon (Falco eleonorae), lanner falcon (Falco biarmicus), levant sparrowhawk (Accipiter brevipes), and Bonelli’s eagle (Hieraaetus fasciatus). Endemic amphibia and reptile species and a large number of threatened butterfly species are also associated with certain parts of the ecoregion.
In addition to coastal tourism development and urbanization, the ecoregion is threatened by water shortage and pollution problems, forest fires, and unsustainable collection of rare plants.
Ecoregions are areas that:
 Share a large majority of their species and ecological dynamics;
 Share similar environmental conditions; and,
 Interact ecologically in ways that are critical for their long-term persistence.
Scientists at the World Wildlife Fund (WWF), have established a classification system that divides the world in 867 terrestrial ecoregions, 426 freshwater ecoregions and 229 marine ecoregions that reflect the distribution of a broad range of fauna and flora across the entire Earth.
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- Digital Map of European Ecological Regions (DMEER), Version 2000/05
- Heath, M.F., and M.I. Evans, editors. 2000. Important bird areas in Europe: Priority sites for conservation. 2 vols. BirdLife International, Cambridge, UK.
- IUCN 2000: The Global Redlist of Species, of the International Union for the Conservation of Nature.
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