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.
Water vole (North America)
Their main source of food is vegetation, including leaves, stems, grasses, sedges, willows, and sometimes seeds or insects. Their food source varies significantly depending on geographic location. Studies have shown that water voles have a very high metabolic rate, and therefore don't have to consume as much food as other rodents their size. Most often, water voles feed on the subterranean portion of plants, which are available to them year round. There is no evidence that they store food for the winter. During the winter they are seen to dig tunnels through the snow, and usually do not surface above the snow once 6 cm have accumulated (approx. 7 to 8 months of the year). 
Water voles are most active at night, and they travel between tunnels, nests and waterways by means of surface runways 5–7 cm wide through the vegetation. Often tunnel or burrow entrances are found either at water level or submerged along the river banks. They construct these subterranean tunnels and nests just below the roots of the vegetation (about 4–6 cm below ground) during the breeding season (June through late September). Females give birth and care for her young in these underground nests, lined with leaves and grass.