The Meadow Viper (Vipera ursinii) is the smallest and the less venomous species of vipers found in Romania.
It is an endangered species and in the Danube's Delta it can be seen in the sandy and arid areas, such as the Portița, Letea and Peridava hills.

The Meadow Viper is a small viper with a thick body. Its skin colour varies from greyish to yellowish. On the back of its head it has 1 or 2 darker A shaped spots. Its head is wide, with small eyes, which are bordered by 6 to 10 scales. Its snout is sharp and slightly upturned. Its backside is a light grey or an olive brown, with a zigzag dark stripe, with black borders, on it.
On average, the adults reach 40 to 50 cm long and in exceptional cases, even up to 60 to 80 cm long. During daytime, the Meadow Viper covers great distances in search of food. It feeds on grasshoppers, crickets, lizards, frogs or small mammals.

The amount of poison in its venomous gland is small. Its prey is swallowed alive, without being injected with venom.
The Meadow Viper is a viviparous species and due to this fact, the female will give birth to 3 to 22 snakelets, during July or August. They will reach maturity after 3 years.

The Meadow Viper hibernates in rodent holes or in hollows. It comes out of hibernation in spring, during March or April.