I recently watched an episode of the PBS series NATURE titled Woodpeckers: The Hole Story. Narrated by Paul Giamatti, the documentary explores what makes woodpeckers special. It had me thinking about the species of woodpeckers found in North Dakota and their importance to our ecosystem.
Species in North Dakota
Robert Steward listed 7 species of woodpeckers in his book Breeding Birds of North Dakota from 1975: Downy, Hairy, Red-headed, Red-bellied, Yellow-bellied sapsucker, Yellow-shafted flicker, Red-shafted flicker, and Pileated woodpecker.
I assume most everyone is familiar with at least a few of these woodpeckers, but I suspect that little thought is given to the importance of these birds in the community, particularly forests and woodlands. Woodpeckers may be considered keystone species in these communities. A keystone species can be loosely defined as a species that is an important component of the community and has a disproportionately large effect on it. So, if the woodpecker populations are doing well, there is a good chance other forest species are also doing well. As such, identifying and protecting keystone species can help ecologists preserve and conserve the communities.
Feeding habits
Woodpeckers, of course, feed largely on insect, spiders, and the like. As such they help keep those populations in check. And piliated woodpeckers are particularly fond of carpenter ants. If you see some sawdust like material at the base of a tree, it is good indication that carpenter ants are active there. And seeing large, deep, oval excavations on the tree trunk and woodchips on the ground at the base of the tree are signs that the pileated woodpeckers have been after them.
Cavity nesting importance
As most everyone knows, woodpeckers excavate cavities in the trees for nesting. And those cavities, perhaps with a little upgrading, may be subsequently used by a wide range of species of animals. Although we may not think of house wrens as cavity nesters, along with a long list of other birds that rely on cavities for nesting includes tree swallows, chickadees, nuthatches, kestrels, and screech owls, as well as wood ducks, hooded mergansers, buffleheads, and goldeneyes. It has been estimated that somewhere around 20% of all bird species use cavities for nesting or roosting.
So, the next time you see a woodpecker, give some thought to their importance to community structure, function, and diversity. And if you are planning some spring cleaning, including taking out some dead or dying trees, consider, if you can, leaving them for the woodpeckers and all the other species that benefit from them.
