A Marbled Murrelet.

The marbled murrelet is a small seabird from the North Pacific. It is a member of the auk family. It nests in old-growth forests or on the ground at higher latitudes where trees cannot grow. Its habit of nesting in trees was suspected but not documented until a tree-climber found a chick in 1974, making it one of the last North American bird species to have its nest described.