The red-breasted nuthatch is a pretty flexible bird. Its range covers a good portion of Canada and the United States. It is normally solitary but will join other birds to feed. They will also group during a particularly harsh winter, either temperature or available food, to exit en masse and migrate short distances to better conditions. They feed on both seed, making them relatively common at bird feeders, and insects. And they are opportunistic. If there is a large insect population, for example the mountain pine beetles, their population will expand as they feed on the overwintering larvae, even if there is a shortage of cavity nests for the birds to take shelter in.
One of the identifying traits of this bird, and other nuthatches, is how they move around a tree. They will move up, down, and sideways, and can often be seen travelling on the trunk with their head down. They do not, unlike woodpeckers, rest on their tail.
There are two main types of nuthatches that I’ve seen at the bird feeder. The red-breasted which is pictured above and the white-breasted. The white-breasted is bigger and has a mostly white head, lacking the black stripe over the eye of the red-breasted. These two species are likely going to have opposite responses to climate change. The white-breasted nuthatch, which currently has a smaller range than the red-breasted is predicted to increase in abundance, moving further south. The red-breasted nuthatch on the other hand will likely decrease due to a predicted decrease in balsam fir. Of course, continued expansion of mountain pine beetle may benefit this bird in some areas of its range, although the long term stability of this population growth is in question.
We know that frogs will respond differently to climate changes than birds will, but this shows that two closely related species, and the same species in different areas of its range, may respond differently to the complex changes that are in store if things continue the way we are going. This highlights the need for region specific research. But more so, to me, it highlights the importance of figuring out how humans can fit within ecosystems instead of on top of them.
The Sibley Field Guide to Birds of Western North America by David Allen Sibley
Atlas of Climate Change Effects in 150 Bird Species of the Eastern United States
Red-breasted Nuthatch in The Cornell Lab of Ornithology: All about Birds
Red-breasted Nuthatch in The Boreal Avian Modelling Project
A. R. Norris & K. Martin. (2010). The perils of plasticity: dual resource pulses increase facilitation but destabilize populations of small-bodied cavity nesters published. Oikos 119(7): 1126-1135. DOI: 10.1111/j.1600-0706.2009.18122.x
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