Q: Here's a mystery for you: During a dry period I noticed a robin in my backyard with what looked like mud all over its chest, and later I found that our birdbath was very muddy. What was going on?
A: The muddy robin you observed was almost surely a female during the busy days of building her nest. After she'd built a base of plant fibers and twigs, the robin gathered up balls of dirt in her beak and stopped at your birdbath to wet it down (since there was no ready-made mud available). Then she flew to her nest and packed the mud down to create nest walls.
She got muddy herself as she squatted and turned in the nest to tamp the mud into place and make sure the space was a good fit, important as she faces two weeks of incubation duty.
Robin nests are heavy and well-built; sometimes a female will re-use an old nest as she begins the second brood.
Unusual feeder birds?
Q: I noticed some yellow-rumped warblers at my suet feeders in early May, something I've never seen before. Is this unusual?
A: The prolonged cold weather this spring drove many of these warblers to bird feeders when they couldn't find the insects they usually feed on. Readers reported seeing warblers eating suet, seeds and even peanut bits. One reader sent a photo of a yellow-rumped warbler eating the grape jelly she'd put out for orioles. Flocks of the warblers also foraged in the street, apparently eating seeds that dropped from boulevard trees.
This is the earliest warbler species to arrive in our area, and their survival strategy includes being willing to try new foods.
Different eagle
Q: I saw what I think is a golden eagle perched in our big oak tree. It wasn't a bald eagle or a hawk, because I know those, and it was the biggest bird I've ever seen.