Rhynchophanes mccownii

Sparse short-grass plains, plowed and stubble fields, and areas of bare or nearly bare ground (AOU 1983). Use grasslands with little litter (Felske 1971) and low vegetation cover (DuBois 1935, Creighton 1974), such as that provided by shortgrass or heavily grazed mixed-grass prairie (Saunders 1914; Finzel 1964; Wiens 1970; Maher 1973, 1974; Creighton 1974; Oberholser 1974; Porter and Ryder 1974; Stewart 1975; With 1994a; Prescott and Wagner 1996). Cultivated lands also may be utilized, including small-grain stubble fields, minimum- and conventional-tilled land, and summer fallow fields (Felske 1971, Stewart 1975, Martin in prep.), although, historically, agricultural lands were avoided (DuBois 1935, Mickey 1943). Early-season abundance of nesting birds in cropland fields in southcentral Alberta showed a positive correlation with percent bare ground, and productivity appeared to be negatively correlated with the vertical density of forbs (Martin in prep.). Often breed on high, barren hillsides with southern exposures (Giezentanner 1970a,b; Felske 1971; Creighton 1974). Blue grama (BOUTELOUA GRACILIS) and buffalo grass (BUCHLOE DACTYLOIDES) are dominant plants in nesting areas (DuBois 1935, Cassel 1952, Creighton 1974).

Nests usually in a scrape on the ground at the base of a bush or clump of grass, or beside cattle dung. Nests beside shrubs may be subject to heavy predation by ground squirrels (With 1994a). Nests tend to be oriented to the north (With and Webb 1993), and about one-third to one-half of nests are placed near clumps of grass, shrubs, plains prickly pear (OPUNTIA POLYACANTHA), or cowpies (DuBois 1935, Mickey 1943, With 1994b). However, shrubs and prickly pear near the nest may facilitate depredation by providing protective cover to predators. In northcentral Colorado, for example, 75-80 percent of nests placed near shrubs or prickly pear were depredated (With 1994b). Nests depredated during incubation had six times more shrub cover within 1 meter of the nest than did successful nests.

In northcentral Colorado, nests were exposed completely to solar radiation at midday and had 45 percent total exposure per day (With and Webb 1993). High exposure to solar radiation may ameliorate cold stresses associated with an early breeding season. Nests constructed later in the season were more likely to be constructed near vegetative cover than those constructed earlier in the season (With and Webb 1993). In southeastern Wyoming, percent vegetation coverage within 5 centimeters of the ground was higher in occupied territories than in unoccupied territories (Greer and Anderson 1989). Occupied territories also had fewer cowpies, less lichen, and lower forb coverage than unoccupied areas.

Area requirements vary by region. Reported territory sizes were 0.6 hectares in southeastern Wyoming (Greer and Anderson 1989), 0.5-1.0 hectares in Saskatchewan (Felske 1971), and 1-1.5 hectares in central Colorado (Wiens 1970, 1971; With 1994a). Pairs often nest near each other (Mickey 1943, Felske 1971). In winter may be seen with flocks of horned larks.

The breeding season extends approximately from mid-March through mid-October (Mickey 1943, Giezentanner and Ryder 1969, Felske 1971, Creighton 1974, Salt and Salt 1976, With 1994a), but may remain on the breeding grounds as late as mid-November in some locations (Johnsgard 1980). The female incubates three to four, sometimes up to six, eggs for 12 days. In northeastern Colorado, usual clutch size was three (With 1994a). Nestlings are altricial. Young are tended by both adults, leave nest in 10 days, and fly 12 days after hatching (Terres 1980). Second broods were reported in northcentral Colorado and in Montana (DuBois 1935, Strong 1971). Second broods may be initiated as soon as three weeks after fledging of the initial brood, but may be limited by female energy reserves (Felske 1971, With 1994a).