Of the seven woodpeckers that can be found in Iowa, five are year around residents and the other two are migratory visitors. One of the migratory ones, the northern flicker, is present right now, but gathering in flocks as evidenced by all of the examples that I was watching this weekend.
I'll choose to write about all of the others and finish up with the northern flicker. Why? No really good reason other than because it's my column.
Most of the woodpeckers that we have here are primarily black and white. Probably the most common of those woodpeckers is the little black and white downy. They frequent feeders in both urban and rural settings wherever there are enough big trees around. Their main native food, like all woodpeckers, is insects, both adults and their larvae. They readily feed on sunflower seeds and suet at feeders, and it's not unusual to see them pecking on corn.
The larger hairy woodpecker is identical to the downy in almost every way. That can make distinguishing between them difficult at times. They have the same black and white barred pattern on their back, white breasts, and the males sport a little red cap on the back of their head. So sometimes you are doing a bit of guessing between whether you are looking at a large downy or a small hairy. I never figure it makes a lot of difference to anyone but another downy or hairy.
The red-headed woodpecker was once common especially in rural areas, but sadly their numbers have suffered large declines. Their striking red head and bold black backs with large white wing patches are easily identifiable. Males and females are identical. An unusual habit among these woodpeckers is that they have been observed flying out to catch insects on the wing.
The red-bellied woodpecker has a bright red cap on the top of its head and despite the name only has a slight blush of red on its belly between its legs. If you live close enough to larger woodlands, it will come to feeders for sunflower seeds and suet.
King (or king-sized) of all the woodpeckers is the crow-sized pileated woodpecker. They are uncommon but permanent residents of larger Iowa woodlands to our north and east. I have seen them along the Iowa and Cedar River corridors but never in Grundy County. They are unique in having a bright red crest on their head, bold white stripes on their unusually long neck and a nearly solid black back. Their size permits them to excavate much larger holes than other woodpeckers. Wood ducks often nest in abandoned pileated holes.
All of the aforementioned woodpeckers share a common trait of having sharp, barbed tips on their tongues, which can be extended well beyond the end of their bills. Tree-feeding woodpeckers drill into the tunnels that insect larvae eat just under the bark. Their tongues can then spear the grubs and draw them out.
The last two woodpeckers are the migratory ones. These are the yellow-bellied sapsucker and the northern flicker. Both of these have bristled, brush-like tips on their tongues. The yellow-bellied sapsucker is typically seen in Iowa only as it passes through during spring and fall migrations. These have red on the front of their head and a blush of yellow on their bellies. They have a very unique feeding technique which involves drilling straight lines of shallow holes into thin tree bark. The holes then fill with sap and the bird returns later to lap up the sap and insects that it attracts. The straight-lined patterns of holes can be seen on some species of trees for years to follow.
The northern flicker, unlike all the other woodpeckers, it is not primarily black and white. Rather, is appears light brown and gray with unique yellow shafts on its flight feathers, a white rump that's prominent in flight, a spotted breast and yellow underwings. In fact, you may have learned the name of this bird as the yellow-shafted flicker. They are one and the same bird only northern flicker is now the accepted common name in the bird watcher world. Interestingly, they excavate nest holes in dead trees like other woodpeckers, but feed on the ground, primarily on ants that they sweep up with their brush-tipped tongues. Flickers do nest here but usually migrate farther south.