Trumpeter swan

Description:

The Trumpeter Swan (Cygnus buccinator) is the heaviest bird native to North America and is, on average, the largest extant waterfowl species on earth. It is the North American counterpart and a close relative of the Whooper Swan of Eurasia, and even has been considered the same species by some authorities

Notes:

These birds feed while swimming, sometimes up-ending or dabbling to reach submerged food. The diet is almost entirely aquatic plants. They will eat both the leaves and stems of submerged and emergent vegetation. They will also dig into muddy substrate underwater to extract roots and tubers. In winter, they may also eat grasses and grains in fields. They will often feed at night as well as by day. Feeding activity, and the birds' weights, often peaks in the spring as they prefer for the breeding season.[13] The young are fed on insects, small fish, fish eggs and small crustaceans along with plants initially, providing additional protein, changing to a vegetation-based diet over the first few months