Short-billed Marsh Wren or Grass Wren.
They breed in wet meadows and marsh edges in eastern North America and central Canada. They migrate south to winter in southeastern United States, and the entire Gulf Coast south through eastern Mexico.
These small songbirds measure 3.9 - 4.7 inches in length (including the tail).
They are brown above with pale streak on the back. Below they are light brown, except for a white throat and chest. The bill is short and thin. There is a dark cap with pale streaks, a faint line over the eye. .