The videos labeled "mating" and "courting" illustrate the behaviors described in the Birds of North America as "Nest-scraping display" and "Tilt Display":

"Nest-scraping display . Generally occurs during courtship and just prior to copulation. A courting male walks about on his territory, deliberately tossing aside shell fragments or pebbles. Periodically, he stops, squats, and, leaning far forward on his breast, pivots to the right and left, while simultaneously kicking sand backward. This creates a shallow scrape in the sand that may eventually be used as a nest, or it may be one of many scrapes dug out before a final nest scrape is chosen. During nest-scraping, he utters the “nest-scraping call” (See Vocalizations). If a female is nearby, male may intensify digging and number of scrapes dug. Late in courtship, females may also dig scrapes but not as intensely as males, and without calling.

Tilt display. Following nest-scraping, a male may stand in a scrape with a female nearby, lower his head at about a 30^°angle, spread wings, and raise his tail, fanning it at a 30^°angle. Female crouches and walks underneath the male’s tail. She stands under the male until he walks away and performs another tilt display. Late in courtship, this display precedes mounting and copulation. Just prior to copulation, the male walks slowly toward the female in a low gliding crouch with head held below the horizon and drawn well into the body. Nearing her, he gradually rises into an erect posture with neck outstretched, breast band broadened, and breast expanded. Simultaneously, he beats a high-stepping and increasingly rapid tattoo with both feet (Fig. 5). Upon reaching the female, he may continue the tattoo for several minutes before flapping his wings and mounting. Male may remain on the female’s back for up to 1.5 minutes before copulation takes place. Both preen after copulation; Great Lakes males continue to tattoo and females may visit scrapes subsequently used for nesting (J. Stucker and C. Haffner pers. comm.). On occasion, females mount males for copulation but do not use the tattoo step prior to jumping on their backs (Haig and Oring 1988c). Males exceedingly attentive and guard mates prior to clutch completion (J. Stucker and C. Haffner pers. comm.)."