Northern Rough-winged Swallow Stelgidopteryx serripennis Audubon       Field Guide IDs: NG-324; G-220; PE-204; PW-pl 43; AE-pl 333; AW-pl 354; AM(II)-302 Nest Location Nest Type Eggs & Mating System Dev. & Parental Care Primary & 2ndary Diet.. Foraging Strategy F I: 12 DAYS ALTRICIAL SHRUB CULVERT (4 feet+) CREVICE MF 5-6 (4-8) MONOG F: 19-21 DAYS MF BREEDING: Open country, savanna, esp near running water. 1 brood. DISPLAYS: In courtship flight, males pursue females, displaying white feathers at lower base of tail. NEST: At end of burrow 4'-5' (l'-6') deep, or in other cavity or niche; of grass, leaves weed stems, occ moist horse dung, no feather lining. In addition to occ excavating burrows, nest in deserted kingfisher burrows, rodent holes, and a wide variety of niches under bridges and wharves, in culverts, sewer pipes, etc. EGGS: White, unmarked. 0.7" (18 mm). DIET: Entirely insects; occ taken from ground. CONSERVATION: Winters s to Panama. NOTES: Usu solitary, occ loosely colonial. Often nest in Bank Swallow colony, where they perch on roots protruding from bank, something Bank Swallows never do. Function of serrations on outer primary feathers (from which name is derived) is unknown; possibly function to produce sounds in courtship flight. STANFORD. NOTES: Uncommon forager on campus from spring through fall, often seen foraging over Lagunita in spring. Not known to breed on campus. ESSAYS: Masterbuilders; Nest Materials; Birds, DNA, and Evolutionary Convergence; Nonvocal Sounds REFERENCES: Lunk, 1962; Ricklefs, 1972.