20120221_127-001 - White-breasted Nuthatch (Sitta carolinensis)
The White-breasted Nuthatch is normally territorial throughout the year, with pairs staying together. The male has to spend more time looking out for predators when he’s alone than while he’s with his mate. That’s the pattern for most birds, and one reason why birds spend so much time in flocks. But the female nuthatch has to put up with the male pushing her aside from foraging sites, so she spends more time looking around (for him) when he’s around than when she is alone.
In winter, White-breasted Nuthatches join foraging flocks led by chickadees or titmice, perhaps partly because it makes food easier to find and partly because more birds can keep an eye out for predators. One study found that when titmice were removed from a flock, nuthatches were more wary and less willing to visit exposed bird feeders.
If you see a White-breasted Nuthatch making lots of quick trips to and from your feeder – too many for it to be eating them all – it may be storing the seeds for later in the winter, by wedging them into furrows in the bark of nearby trees.