Romania hosts Europe's largest brown bear population (6,000–7,000), along with gray wolves (Carpathian subspecies), Eurasian lynx, wild boar, red deer, roe deer, chamois, red fox, European hare, hedgehogs, marmots (Alpine and Carpathian), moose (north/east), European rabbit, raccoon (invasive), red squirrel, mustelids (weasel, stoat, polecat), and 20 bat species.
Raptors include golden eagle, white-tailed eagle, lesser spotted eagle, peregrine falcon. Corvids (magpie, jay, crow), finches, larks, owls (barn, tawny, long-eared), passerines, pheasants, pigeons, thrushes, tits, and woodpeckers are widespread.
Lizards (common, sand, green), snakes (grass, dice, viper), turtles (European pond, Hermann's tortoise), frogs (common, green, marsh), newts (smooth, palmate, alpine), salamanders (fire, alpine, Carpathian).
Carp (common, crucian, tench), catfish (European, wels, burbot), eel, perch, zander, pike, trout (brown, rainbow), Atlantic salmon, and the endangered Danube sturgeon.
Over 1,000 bee species, 2,000+ butterflies, 100+ dragonflies, 700+ grasshoppers, 1,000+ spiders.
Romania's Carpathian Mountains and Danube Delta make it a European biodiversity hotspot.