Bulgaria's vertebrate fauna is among the most diverse in Europe. The zoogeographical regions are three: the Eurosiberian region, encompassing the Danubian Plain and the mountainous regions of the country; the Irano-Turanian Region encompassing Southern Dobrudzha; and the Mediterranean region that includes the Upper Thracian Plain, the lower Struma valley and the Black Sea coast. Bulgaria is inhabited by around 100 mammal species, including brown bears, grey wolves, Eurasian lynxes, golden jackals, red deer and roe deer among other. The avian fauna is represented by 426 species of birds, which is the second highest number in Europe. Important conservation species are the eastern imperial eagle, the cinereous vulture, the great white pelican, the Dalmatian pelican, etc. The reptiles and the amphibians found in Bulgaria are 38 and 20 species respectively. The ichthyofauna of the country has not been fully researched. As of 2000 there are 207 fish species. There are an estimated 27,000 species of insects and other invertebrates.