Western Kingbird Tyrannus verticalis Say       Field Guide IDs: NG-298; G-206; PE-194; PW-pl 41; AE-pl 467; AW-pl 421; AM(II)-286 Nest Location Nest Type Eggs & Mating System Dev. & Parental Care Primary & 2ndary Diet.. Foraging Strategy F I: 18-19 DAYS ALTRICIAL SHRUB 15 feet - 30 feet (5 feet - 40 feet) ? 3-4 (3-7) MONOG F: 16-17 DAYS MF BERRIES HOVER & POUNCE BREEDING: Savanna, dry open country, agricultural lands, riparian woodland. ? broods. DISPLAYS: Male performs frenetic courtship flight, darting into air, fluttering, vibrating feathers, and trilling. NEST: Usu on horizontal branch against or near trunk of tree or on human-built structure; of variable materials, thickly and finely lined with hair, cotton, plant down. EGGS: White, creamy, pinkish, mottled with browns, gray, lavender, occ concentrated at large end. 1.0" (24 mm). DIET: Insects and berries. CONSERVATION: Winters from s Mexico s (except Yucatan) to s w Costa Rica. Rare cowbird host. Range has expanded since 1900 as suitable nest sites became available due to expanding agriculture. NOTES: Reproductive success varies with insect abundance; when insects abundant, clutches are larger and initiated earlier, nestlings are fed more often and grow faster. On territory very aggressive toward crows, hawks, etc. STANFORD. NOTES: Uncommon migrant and rare summer resident at the Dish, fairly rare elsewhere on campus. Most common in spring, but occasionally a pair will linger to nest at the Dish. Feeds on insects while making long sallies over open fields. ESSAYS: Passerines and Songbirds; Bills; Masterbuilders; Range Expansion REFERENCES: Blancher and Robertson, 1984, 1987; MacKenzie and Sealy, 1981.