BLANE KLEMEK COLUMN: What is a goatsucker?
The Minnesota Department of Natural Resources will be doing a woodpecker and goatsucker survey this season in the Red Lake Wildlife Management Area (WMA).
The DNR's staff stationed at Red Lake WMA will conduct the survey. A lot of good wildlife research and wildlife survey work comes out of Red Lake WMA every year, and this survey is yet another.
But goatsuckers, you say? What's a goatsucker?!
Birds that are called "goatsuckers" include the eastern whip-poor-will as well as the common nighthawk, both of which occur here in Minnesota. According to "The Sibley's Guide to Birds," the name and meaning of "goatsuckers" is ". . .based on a superstition that goes back well over 2,000 years." Nocturnal birds such as they are, each are mysterious and misunderstood.
Also from "Sibley's," an author in 77 AD once wrote about goatsuckers, ". . .They bee night-theeves; for all the day long they see not. Their manner is to come into the sheepeheards coats and goat-pens, and to the goats' udders presently they goe, and suck the milke at their teats. And looke what udder is so milked, it giveth no more milke, but misliketh and falleth away afterwards, and the goats become blind withal."
And so it is that our own eastern whip-poor-will and common nighthawk became collectively known as "goatsuckers," though not a shred of truth exists for the unusual moniker and superstition. Of the goatsucker family, Caprimulgidae, some 83 species belonging to the family occur worldwide, seven of which can be found in North America.
Like other members of the family, the plumage of whip-poor-wills and nighthawks is cryptically patterned, making them nearly impossible to detect during the day, let alone at night, unless of course they're observed in flight during the light of day.
Possessing short legs, small feet, and small bills, goatsuckers make up for these anatomical deficiencies with large heads and enormous mouths. This last feature equips goatsuckers so wonderfully well for the lifestyles they lead.
Most of their prey is flying insects such as moths and mosquitoes, so having large and wide mouths enable these acrobatic and graceful flyers to easily capture insects on the wing. Additionally, whip-poor-wills and most other caprimulgiform birds have long bristles that grow around their bills. The bristles aid the birds in catching insects as well as protecting their eyes from inopportune encounters with insects.
When looking at a field guidebook of birds, whip-poor-wills and nighthawks, if not all North American goatsuckers, look nearly identical. But subtle differences separate the species if you look closer. While the whip-poor-will, for example, has moderately broad and rounded wings, the nighthawk flies about on long, white-barred pointed wings. For sure, the nighthawk's silhouette, which is very raptor-like, nearly that of a falcon, is often mistaken for a bird of prey. As such, its name is really a misnomer, for the nighthawk is neither a true nocturnal bird nor is it a hawk.
As sweet and captivating a sound as the song of the whip-poor-will is in the dark of night, male common nighthawks also produce calls and sounds worth mentioning. In the spring of the year, male nighthawks perform aerial flight displays above their breeding grounds that are accompanied by loud "booming" sounds.
Nighthawks accomplish the sounds in a very unusual manner. When the bird reaches the proper altitude, he enters into an abrupt and steep dive. As the diving nighthawk nears the earth, he bends his wings downward seconds before coming out of the dive. Loud booms or clap-like sounds are produced as air rushes through the tips of his wings. Nighthawk calls, which are normally vocalized while in flight, are described as "peents," which are very similar to the calls made by male American woodcocks.
Indeed, we are fortunate to have both of these remarkable "goatsuckers" as summertime residents here in northern Minnesota. It won't be long when both species depart for their northern breeding grounds from places as far away as the Bahamas and South America. Unique birds to be sure—nighthawks and whip-poor-wills—are as interesting as they come as we get out and enjoy the great outdoors.
Blane Klemek is a Minnesota DNR wildlife manager. He can be reached at firstname.lastname@example.org.