Central Iowa has known but one kind of dove over most of its history. The common mourning dove has always called Iowa home. Incredible flocks of migrating passenger pigeons, once thought to be the most numerous bird in the world, might have passed over at least eastern Iowa on occasion, but they nested farther east in dense hardwood forest. Forest habitat loss in the 1800s and uncontrolled hunting doomed that specie to extinction about a century ago. Common pigeons, more properly known as rock doves in their wild state, were originally an Old World specie that was brought to our shores by colonists as early as the 1600s. They spread nationwide as growing cities and farms created habitat to their liking.
The first Eurasian collared doves began to be seen in our area about 20 years ago. These doves are lighter colored and larger than our native mourning dove. Some of them escaped from captivity in the Bahamas in 1974 and soon found their way to Florida. They spread rapidly north and west and were usually associated with urban habitat. They’re now spreading to rural areas, as well, and have expanded their range across the nation in only a few decades. Pigeons (rock doves) seemed to find their own niche and not compete heavily with our native doves. The jury is still out on how the rapidly expanding population of collared doves will affect our native mourning doves and several other dove species from the Southwest.
Doves and pigeons are a large worldwide family. They share some unique characteristics compared to other kinds of birds. Their diet is composed entirely of vegetable matter. A few kinds of doves eat some fruits and greens but dove’s primary food is seeds. Most other birds consume some animal foods, such as insects, at least when they’re young, even when they’re primarily seed-eaters as adults. Babies of the dove family are fed “pigeon milk.” Pigeon milk isn’t just seeds that the adults ate. It’s created in the adult’s crops, a food storage pouch at the base of the neck. Cells in the walls of their crops become engorged with nutrients and then are sloughed off and regurgitated as pigeon milk for the young. Doves also have an unusual ability among birds to suck up water through their bills much like we would through a straw. Most birds have to pick up water in their bills and tip their heads back to let it trickle down their throats when they drink.
Some local friends spotted an unusual bird under their feeder a couple of weeks ago. They recognized it as a white-winged dove and even got some pictures of it. White-wings are larger than our local mourning doves and about the size of collared doves. They’re gray with a large white patch on the wing that shows even when it’s folded. It was a first sighting of this dove for Story County and is one of only a few that have been seen in Iowa. White-winged doves are native to the desert southwest, but a few sometimes wander widely, even into eastern North America.
Some other friends recently hosted a pair of red crossbills at their feeder for a couple of hours. Flocks of them occasionally drop this far south in winter, but summer sightings are quite rare. They nest across southern Canada and in the mountain west where they can access plenty of their favorite food, pine seeds pried from pine cones with their scissors-like crossed mandibles. Ruddy ducks sometimes migrate through Iowa, but their nesting range is farther west. An unusual summer sighting of a male ruddy duck was made on a flooded field north of the old Milford School just after the recent heavy rains. These small, chunky, rust-colored diving ducks sport a flashy sky-blue bill, a white face, and a long stiff tail that’s often held erect like a little wren.
Birds are mobile and can sometimes turn up far from their normal home ranges. Sometimes they’re blown far off course by storms. Other times hunger drives them to wander when their preferred foods become hard to find. Climate change is shifting the breeding ranges of some birds farther north. A few birds (just like people) just seem to get an itch to travel and explore. This gives even casual birders a chance pick up rare and unusual sightings if they keep their eyes open.
Steve Lekwa is a former director of Story County Conservation.