Newton, NJ, United States
This nest has been build upon 6 times over, in the same spot. You can see one nest cup on top of another balanced between window rail and the window.
It was originally started as a Robin’s nest, but from year two through six, it was occupied and built each successive year by the Carolina Wren that returns year after year. The Carolina Wren stacks twigs and sticks in the space between top of the nest and the roof eve so there is only very small space to enter the nest cup, and it in turn, minimizes intrusion by predators.