Dowitchers, Godwits. Willets. Phalaropes. Many Minnesotans may not recognize these funny names as belonging to some of our native birds. But there I was parked alongside a county road near Slayton one mid-May several years ago, studying these avian oddballs as they probed, picked, plunged, and whirled about in shallow water in the middle of a muddy cornfield.
Despite the rather mundane scenery of a wet field in Murray County, this type of habitat is absolutely essential to shorebirds, a group of birds most often associated with shallow water. While much less aesthetically impressive than the arctic destinations to which these birds were headed, mudflats and puddles—which are plentiful in western Minnesota in spring—are just as necessary to the annual migrations of thousands of shorebirds like the ones I was watching through my spotting scope.
Minnesota is home—at least temporarily each year—to a total of 32 species of shorebird. While some of these birds do breed here, others seen in the state are present for only a few weeks during migration. As these birds stop to refuel in our state during their long journeys north in the spring and south in the fall, they provide keen observers the opportunity to view their rather strange and even amusing forms.
The Avocet Family (Recurvirostridae)
The American avocet (Recurvirostra americana) has charisma. About the size of a crow, this shorebird has long bluish legs, a boldly marked black-and-white body, a peach neck and head (white in fall and winter), and a long bill that veers up abruptly near the tip. The avocet wades deeper into the water than smaller shorebirds will go, nodding toward the water's surface while plunging its bill into the mud. Swinging its head left to right in a swaying motion while walking, the avocet uses its bill tip to filter through water and mud in search of invertebrate larvae, a feeding behavior called scything. When the bird detects a morsel, it quickly snatches the bug while pulling its head back to consume the meal.
American avocets can be found just about statewide in April and May during spring migration and then again in August through October during fall migration, although they are found in their greatest numbers in spring in southern and western Minnesota. A rare breeder in the state, the bird has been spotted in recent summers in northwestern Minnesota, including at the North Ottawa floodwater impoundment, a project by the Red River Watershed Management Board, the Bois de Sioux Watershed District, and the Minnesota Department of Natural Resources that creates important stopover and nesting habitat for shorebirds and other bird species.
The black-necked stilt (Himantopus mexicanus)—a slightly smaller, black-and-white cousin of the American avocet—is increasingly being seen in Minnesota and has even nested here in recent years. With a shorter, straighter bill than the avocet and comically long, pink legs, this western species is poised to become the next addition to the list of Minnesota's regularly occurring shorebirds.
The Plover Family (Charadriidae)
The best-known shorebird in Minnesota may be the killdeer (Charadrius vociferus) , which unlike most shorebirds is more often found away from water than near it. Named for its loud, two-note "kill-deer!" call, which it gives frequently, this bird is a common breeder throughout Minnesota. Watch for it near ballparks, golf courses, agricultural fields, and even front yards, where vegetation is cut low or nonexistent and the birds are able to hide their nests and their bespeckled, camouflaged eggs amid mostly bare ground.
Should you approach a killdeer nest too closely, expect to see the incubating adult run off and pretend to have a broken wing while making high-pitched keek sounds to get your attention. This might seem funny and odd, but it's a very successful way to distract a would-be predator. The bird will continue this ruse on foot or by flying short distances until it is satisfied that its follower is far enough away from the nest, and then miraculously fly back. Other shorebird species use a similar broken-wing display to protect the nest.
A close relative of killdeers, semipalmated plovers (Charadrius semipalmatus) look like smaller, one-banded versions of their larger cousins. "Semipalmated" refers to their partially webbed feet, which are not webbed to the toes as in ducks or geese. Several other shorebird species share this feature. Look for semipalmated plovers during migration in typical shorebird habitat like mudflats and other wet areas, but know that killdeers will sometimes frequent wetter areas too.
Roughly the same size and shape as semipalmated plovers, piping plovers (Charadrius melodus) can be identified by their paler, silvery upperparts. This species is exceedingly rare in Minnesota but is nonetheless seen annually, mostly during spring migration on Park Point in Duluth, where it nested as recently as 1985.
Both black-bellied plovers (Pluvialis squatarola) and American golden-plovers (P. do-minica) are among the larger shorebirds that can be seen during migration in Minnesota. Although both species can frequently be found among groups of mixed shorebirds in typical shorebird habitat, American golden-plovers are sometimes encountered in flocks of several hundred birds and will more often favor drier habitats like plowed farm fields. In spring, their striking breeding plumage, which is brighter and more uniform in males, makes them stand out from a distance. Their black undersides and either silver (in black-bellied plover) or golden-tan (in American golden-plover) upperparts are separated by thick white stripes. In fall, both species turn a dull gray-brown, creating an identification challenge for even the experienced observer. If the bird lifts its wings, however, identification is easy: Black-bellied plovers have black armpits whereas American golden-plovers have gray, like the rest of their underwings.
The Sandpiper Family (Scolopacidae)
Some of the toughest identification challenges in the world of birding are found in this diverse group of shorebirds, which includes many similarly colored species. Fortunately, almost all of these birds can be found in typical shorebird habitat and are fond of forming mixed-species groups during migration, which means they can be studied in close proximity to one another.
The "peeps" are among the most notorious for posing such problems, and these include four small sandpipers in Minnesota: least (Calidris minutilla) , semipalmated (C. pusilla) , Baird's (C. bairdii) , and white-rumped (C. fuscicollis) .
The least sandpiper is our smallest shorebird, around six inches in length, and the semipalmated sandpiper is only slightly bigger. These two are usually visibly smaller and shorter-winged than the somewhat larger Baird's and white-rumped sandpipers, but to tell the two apart from each other takes diligence. Look for the yellow legs of a least in comparison to the black legs of a semipalmated, but beware that yellow legs covered in mud, which a tiny shorebird often exhibits, can make them look black! Further study will reveal a thicker and straighter bill of a semipalmated versus a thinner, slightly drooping (curved downward toward the tip) bill of a least.
When comparing a Baird's sandpiper to a white-rumped, a Baird's is more sandy-colored on its upperparts than the grayer white-rumped. A white-rumped also has a bill that is reddish at the base and streaking down the sides of its belly, and if you're able to see it in flight the clean white rump sets it apart from not only the Baird's but also other small shorebirds.
Greater and lesser yellowlegs (Tringa melanoleuca, and T. flavipes, respectively) present another identification challenge among migrant shorebirds. When the species are seen together, the size difference is obvious as the greater is bulkier and at least a head taller than the lesser. But when only one species is present, which species is it?
Bill shape and length are key here. A greater yellowlegs has a longer bill about twice the length of its head (viewed from the side) that noticeably turns up from base to tip, whereas the lesser yellowlegs has a shorter bill closer to the length of its head that appears fairly straight.
Solitary sandpipers (Tringa solitaria) and spotted sandpipers (Actitis macularius) both frequently bob their tails up and down when perching or walking, a behavior that sets them apart from most other shorebirds in Minnesota.
Spotted sandpipers, which have prominent dark spots on their undersides in breeding plumage, breed throughout the state and are fairly common along rivers and lakeshores in addition to wastewater treatment ponds. Solitary sandpipers, which look like they are wearing spectacles, are common migrants throughout the state and very rarely breed in wetlands in coniferous habitats of far northern Minnesota.
Pectoral sandpipers (Calidris melanotos), sanderlings (C. alba), dunlins (C. alpina), and stilt sandpipers (C. himantopus) are medium-sized shorebirds that are frequently found among migrant flocks, with pectoral sandpipers being especially abundant in some locations. Sanderlings are fond of sandy or rocky shores of large lakes, where they chase the waves washing ashore, often alongside ruddy turnstones (Arenaria interpres), boldly patterned sandpipers that use their short, upturned bills to flip small rocks where invertebrates might be lurking. Red knots (Calidris canutus), which are about the size of our larger plovers, are also among our rarest shorebird migrants in Minnesota, found almost exclusively along the shore of Lake Superior.
The jumbo shorebirds thankfully stand out in a crowd. In addition to American avocets, these include whimbrels (Numenius phaeopus), Hudsonian and marbled godwits (Limosa haemastica and L. fedoa), and willets (Tringa semipalmata). These four species are less frequently encountered among shorebird concentrations, with whimbrels (like red knots) having an affinity for Lake Superior. Marbled godwits breed in prairies of west-central and northwestern Minnesota, and both Hudsonian godwits and willets are surprisingly more difficult to come across in fall than in spring.
Upland sandpipers (Bartramia longicauda) are almost never found in wet habitats, breeding in prairies of western Minnesota. Likewise, buff-breasted sandpipers (Calidris subruficollis), which are expected during fall migration but virtually absent in spring, prefer sod farms and dry, grassy fields rather than typical shorebird habitat.
The softball-size American woodcock (Scolopax minor), a breeding species in Minnesota that prefers more upland habitats, has one of the most impressive and bizarre courtship displays of any bird, with the male spiraling hundreds of feet into the sky at sunset. Wilson's snipes (Gallinago delicata) signal their territory by creating a "winnowing" sound in flight that resonates across wet meadows and other open areas where the species breeds in Minnesota. Long-billed and short-billed dowitchers (Limnodromus scolopaceus and L. griseus) are shaped like snipe and, also like snipe, feed by repeatedly sticking their long, straight bills into the water in a mechanical manner similar to that of a sewing machine needle. Long-billed dowitchers migrate through the state earlier in the spring and later in the fall than short-billed.
Both Wilson's and red-necked phalaropes (Phalaropus tricolor and P. lobatus) are oddities in the bird world in that the sexual roles are almost completely reversed. While the female still lays the eggs, it is she that is the more colorful sex and competes for males with other females. Once she lays the eggs, the female leaves the male to do the incubating and brooding of the precocial young as she goes off in search of other males with which to mate.
Why this role reversal has evolved in phalaropes and a few other shorebirds still largely remains a mystery. Phalaropes are often found in deeper water among ducks and other water birds, spinning in circles to stir up invertebrates from the depths to the water's surface, resulting in an easy meal. Red-necked phalaropes are migrants through Minnesota, whereas some Wilson's phalaropes breed in sedge meadows—a unique and critical habitat for breeding birds—mostly in the northwestern part of the state.
Despite being located far from any seashore in the middle of a continent, Minnesota is privileged to host a diversity of shorebirds for at least part of each year. Unfortunately, many of these migrating birds face threats to their populations elsewhere along their journeys, from wetland degradation to climate change, that are significantly affecting shorebird populations worldwide and resulting in steep declines for some species. It's important we do our part in Minnesota to ensure these same threats are minimized as the shorebirds complete our leg of the journey, and that begins with learning to recognize and appreciate this remarkable group of birds.