Tyrannidae (Tyrant Flycatchers)
Olive-sided Flycatcher,Contopus borealis. (Fig. 11.19) Male length 6 1/2 in (16.5 cm), female length 6 1/2 in (16.5 cm); male weight 1 1/8 oz (32.6 g), female weight 1 1/8 oz (32.6 g). Fairly common summer resident locally in the White Mountains. Recorded from 8,200 to 10,500 ft (2,500 to 3,200 m).
This large flycatcher breeds only in the higher coniferous forests of Limber Pine, Bristlecone Pine, and Lodgepole Pine. It prefers open stands of mature timber, particularly where high perches and prominent song posts are available. Such perches are in the tops of tall dead and dying conifers. Olive-sided Flycatchers have the highest foraging beat of all North American members of their family, the Tyrannidae.
Figure 11.19
Olive-sided Flycatcher.
They feed mainly on large, flying insects. In contrast, nests are typically built at lower heights, on the outer live branches of Limber or Bristlecone pines. Males may sing continuously, but pairs are usually widely spaced on extensive territories. The easily recognizable song, quick-three-beers , accented on the second note, can be heard from up to 0.5 mi (0.8 km) away. Late migrants passing through the valleys and foothill canyons during late May and early June may also sing occasionally. Reference: Grinnell and Storer (1924).
Western Wood-Pewee,Contopus sordidulus . (Fig. 11.20) Male length 5 3/4 in (14.5 cm), female length 5 1/2 in (14 cm); male weight 1/2 oz (13 g), female weight 1/2 oz (13 g). Common summer resident in the White Mountains, between 7,400 and 9,000 ft (2,260 and 2,740 m) elevation.
This flycatcher is most common in woodland and coniferous forest along streams. Because it prefers to forage from tall trees of open branchwork, dense pinyon and Mountain Mahogany are shunned. Large Quaking Aspen, Bristlecone Pine, and Limber Pine are frequented most commonly. Western Wood-Pewees seek flying insects from moderate heights above the ground; their foraging beat is therefore between that of the Dusky Flycatcher and that of the Olive-sided Flycatcher, with overlap at both
Figure 11.20
Western Wood-Pewee.
the upper and lower levels. Wood-Pewees migrate well into June. Then they may occur in Pinyon-juniper Woodland, willow thickets, and other nonbreeding habitats. The nasal buzz of the Western Wood-Pewee is commonly given throughout the day, even on sunny summer afternoons when few other species of birds are calling. Reference: Marshall (1957).
Dusky Flycatcher,Empidonax oberholseri . (Fig. 11.21) Male length 5 1/4 in (13.5 cm), female length 5 in (13 cm); male weight 2/5 oz (11.6 g), female weight 2/5 oz (11.6 g). Common summer resident in the White-Inyo Range, between 8,200 and 10,500 ft (2,500 and 3,200 m).
Although this species avoids Singleleaf Pinyon except occasionally during migration, most other trees as well as willow thickets are used for breeding. In particular, it frequents Mountain Mahogany groves, streamside aspen woodland, and open forests of Bristlecone and Limber pines. Nests are usually built within 5 ft (1.5 m) of the ground in upright twigs of tall, dense shrubs (such as Wild Rose), aspen saplings, and willows. The adults feed near the nest and higher up in the openings between tall trees. The singing and sentry posts are often well above the ground. Dusky Flycatchers feed on miscellaneous flying insects such as small beetles, wasps, flies, and bugs, all of which are snapped from the air. Reference: Johnson (1963).
Gray Flycatcher,Empidonax wrightii . (Fig. 11.22) Male length 5 1/4 in (13.25 cm), female length 5 in (13 cm); male weight 2/5 oz (11.6 g), female weight 2/5 oz
Figure 11.21
Dusky Flycatcher.
(11.6 g). Common summer resident in the White-Inyo Range from 7,200 to 10,500 ft (2,200 to 3,200 m).
Gray Flycatchers are most numerous in the vast tracts of Singleleaf Pinyon growing on either flat or sloping terrain. They also breed sparingly in sunny stands of Limber and Bristlecone pines up to 10,500 ft (3,200 m) elevation in the Inyo Mountains. This is the highest known nesting station for the species. In other regions, such as near the south end of Mono Lake, they breed in stands of tall sagebrush and Bitterbrush. Such growth does not seem to be used extensively in the White-Inyo mountain area. Nesting pairs prefer medium to large Singleleaf Pinyons near openings with relatively sparse brush. The nest straddles a horizontal branch and is commonly placed right near the trunk. Males commonly perch on a bare twig near the nest tree, where they are conspicuous by virtue of their silvery white underparts and tail-dipping mannerism. Typical perch sites for singing or foraging are within 12 ft (3.7 m) of the ground. Insects are caught from bare or nearly bare patches of ground between sagebrush, Bitterbrush, lupine, and small Beavertail Cactus. Like its relative, the Dusky Flycatcher, the Gray Flycatcher catches small insects while in flight. Although they maintain separate territories, the two species commonly occur side by side where their preferred habitats meet in these mountains. Reference: Johnson (1966).
Figure 11.22
Gray Flycatcher.
Say's Phoebe,Sayornis saya. (Plate 11.1) Male length 6 3/4 in (17 cm), female length 6 3/4 in (17 cm); male weight 3/4 oz (21.6 g), female weight 7/10 oz (20.4 g). Sparse summer resident in the White-Inyo region, between 5,900 and 9,500 ft (1,800 and 2,900 m).
Say's Phoebes inhabit the pinyon-juniper-sagebrush zone in the region. Although the species is not numerous, nesting pairs can usually be seen in arid canyon mouths where sunny gravel banks and/or human constructs are present. Nests are placed on protected shelves in cliffs or buildings, and the adults forage nearby. Insect food is snapped from the air or the ground as the birds momentarily leave their low perches on bushtops or rocks, or as they hover. Postbreeding adults and independent young are widespread in shrubland or ranch country, where they perch singly on fenceposts, wires, or bushtops. Reference: Weathers (1983).
Ash-throated Flycatcher,Myiarchus cinerascens. (Fig. 11.23) Male length 7 1/2 in (18.75 cm), female length 7 in (18 cm); male weight 1 oz (28.6 g), female weight 9/10 oz (26.4 g). Uncommon summer resident in the White-Inyo Range, from the valley floors to approximately 7,500 ft (2,290 m).
This flycatcher inhabits Pinyon-juniper Woodland and brush on warm, dry slopes, and open riparian growth with at least scattered trees. Because much of the foraging
Figure 11.23
Ash-throated Flycatcher.
activity occurs within 20 ft (6 m) of the ground, low perching sites are essential. Bushtops or exposed dead twigs in a dead or dying tree are used most typically. The Ash-throated Flycatcher captures large wasps, flies, beetles, and bugs by means of aerial sorties. Nests are built of twigs and lined with grass in a natural or woodpecker-excavated cavity in an old Singleleaf Pinyon or juniper. Both parents are usually conspicuous near the nest site. Pairs are widely spaced through the habitat on large territories and announce their presence with a loud, rolling ka-brick or prit-wherr call (accented on the second syllable). Reference: Miller and Stebbins (1964).