Scarlet Ibis (Eudocimus ruber) and White Ibis (Eudocimus albus) roosting. Hato Masaguarel working farm and biological station, Guarico Province, Venezuela, South America. The Llanos are flood plains stretching north of the Orinoco River to the Andean foothills, covering 300,000sq km in Venezuela and another 220,000 sq km in Colombia. This area has poor soil but is rich in its river systems which floods in the wet season leaving shallow marshes which nourish a high concentration of birds and animals.