A dollop of snow highlights the once secret spot where a bird built a nest and raised young. Once you develop a search image for these snow-capped baskets perched on limbs or tucked away inside thickets, you can begin to see them everywhere.
Although the birds that built them are away, the habitat, size and shape, materials, and placement of nests can often give us clues about their identity. Birds build their nests without any prior instruction, and yet each builds a nest that is characteristic of its species. Most birds only use their nest for one season, and the nests we see in winter are only those sturdy enough to last through summer and fall storms. Many of the nests are considerably changed by weathering, which can make exact nest identification tricky. But some sturdy nests can be identified in winter with this field guide to bird nests in winter. Also check out this new resource for bird nest ID: Bird Nest Finder – Identifying Aboveground Bird Nests in Eastern North America by Dorcas S. Miller and Cornell Ornithology’s NestWatch resources.
While getting a close look in winter at the empty nest and materials used, you may find a nest has been repurposed as a mouse home or food stash!
I’d like to know where birds go to stay warm in the winter – the ones who do not migrate. I’m surprised that they don’t freeze to death in this below-zero weather! do they use some of these old nests to cuddle in?
Some birds, like chickadees, will shelter in tree holes and crevices, woodpeckers will excavate winter overnight shelters, ruffed grouse burrow into a blanket of snow, and golden-crowned kinglets huddle together for warmth (though about 87% of the golden-crowned kinglets perish every winter!). Here’s a wonderful article that explains these strategies: https://www.allaboutbirds.org/news/how-do-birds-survive-the-winter/