Carolina Wren

From Birds.Cornell.edu
The Carolina Wren is sensitive to cold weather, with the northern populations decreasing markedly after severe winters. The gradually increasing winter temperatures over the last century may have been responsible for the northward range expansion seen in the mid-1900s.
Unlike other wren species in its genus, only the male Carolina Wren sings the loud song. In other species, such as the Stripe-breasted Wren of Central America, both members of a pair sing together. The male and female sing different parts, and usually interweave their songs such that they sound like a single bird singing.
One captive male Carolina Wren sang nearly 3,000 times in a single day.
A pair bond may form between a male and a female at any time of the year, and the pair will stay together for life. Members of a pair stay together on their territory year-round, and forage and move around the territory together.