Virginia rail
The Virginia rail probe with its bill in mud or shallow water, also picking up food by sight. It mainly eat insects and other aquatic invertebrates, like beetles, flies, dragonflies, crayfish, snails and earthworms. It can also eat aquatic animals like frogs, fish and some small snakes, as well as seeds. Animal preys constitute the biggest part of this bird's diet, but vegetation contributes to its diet in the fall and winter.
Holochilus chacarius
The Chaco marsh rat can swim and dive, and can also climb well; it is a herbivore, feeding on a range of plant materials including sugarcane, rice, banana and other crops. It can make underground galleries with several entrances, but nests above ground, building circular structures of grass up to in diameter and often a metre or more above the ground. Litter sizes range from four to nine, and the young mature at sixty days.