Question: The Grand Canyon has how many bird species that breed in the coniferous forests?
About the article "Grand Canyon", section "Upper Sonoran and Transition".

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The Upper Sonoran Life Zone includes most of the inner canyon and South Rim at elevations from .
This zone is generally dominated by blackbrush, sagebrush, and pinyon-juniper woodlands.
Elevations of are in the Mojave Desert Scrub community of the Upper Sonoran.
This community is dominated by the four-winged saltbush and creosote bush; other important plants include Utah agave, narrowleaf mesquite, ratany, catclaw, and various cacti species.
Approximately 30 bird species breed primarily in the desert uplands and cliffs of the inner canyon.
Virtually all bird species present breed in other suitable habitats throughout the Sonoran and Mohave deserts.
The abundance of bats, swifts, and riparian birds provides ample food for peregrines, and suitable eyrie sites are plentiful along the steep canyon walls.
Also, several critically endangered California Condors that were re-introduced to the Colorado Plateau on the Arizona Strip, have made the eastern part of the Park their home.
The conifer forests provide habitat for 52 mammal species.
Porcupines, shrews, red squirrels, tassel eared Kaibab and Abert's squirrels, black bear, mule deer, and elk are found at the park's higher elevations on the Kaibab Plateau.
Above the desert scrub and up to is a pinyon pine forest and one seed juniper woodland.
Within this woodland one can find big sagebrush, snakeweed, Mormon tea, Utah agave, banana and narrowleaf Yucca, winterfat, Indian ricegrass, dropseed, and needlegrass.
There are a variety of snakes and lizards here, but one species of reptile, the mountain short-horned Lizard, is a particularly abundant inhabitant of the piñon-juniper and ponderosa pine forests.
Ponderosa pine forests grow at elevations between , on both North and South rims in the Transition life zone.
The South Rim includes species such as gray fox, mule deer, bighorn sheep, rock squirrels, pinyon pine and Utah juniper.
Additional species such as Gambel oak, New Mexico locust, mountain mahogany, elderberry, creeping mahonia, and fescue have been identified in these forests.
The Utah tiger salamander and the Great Basin spadefoot toad are two amphibians that are common in the rim forests.
Of the approximately 90 bird species that breed in the coniferous forests, 51 are summer residents and at least 15 of these are known to be neotropical migrants.
The Pine Flycatcher ("Empidonax affinis") is a species of bird in the Tyrannidae family, the tyrant flycatchers.
It is found in the montane tropical and subtropical coniferous forests of Mexico and southwestern Guatemala.
Possible sightings of a vagrant bird were recorded in Choke Canyon State Park in southern Texas in January 2009.
If confirmed it would be the first such observation of the species in the United States. 
There are many different species of trees, many coniferous, that grow in the mountains.
Pines, such as Ponderosa pine, Jeffrey pine, Sugar pine, Coulter pine, Lodgepole pine, Single-leaf pinyon, and Knobcone pine all thrive here.
Other coniferous trees, such as White Fir, bigcone Douglas-fir ("Pseudotsuga macrocarpa"), Incense Cedar, and Western Juniper also thrive here.
Canyon Live Oak, California Black Oak, and Pacific Dogwood are other trees that also grow here.
The forest contains an estimated of old growth.
The most common old-growth forest types are mixed conifer Coast Douglas-fir ("Pseudotsuga menziesii var.
menziesii"), Ponderosa Pine ("Pinus ponderosa"), and White Fir ("Abies concolor") forests, Jeffrey Pine ("Pinus jeffreyi") forests, and Lodgepole Pine ("Pinus contorta") forests. 
The Apache trout is the state fish of Arizona, and is one of only two species of trout native to that state, with the other being the gila trout ("O. g. gilae").
It natively lives in clear, cool streams in the White Mountains that flow through coniferous forests and marshes, but has been introduced into several lakes in the area.
The Apache trout is native to the upper Salt River watershed (Black and White rivers) and the upper Little Colorado River watershed.
Apache trout have been introduced into isolated streams outside of their historic range in the Pinaleno Mountains and the North Rim of the Grand Canyon. 
The Northern Parula inhabits various habitats depending on season and location.
This is primarily a forest-dwelling species, but the northern and southern breeding populations select different habitats.
In general, abundance of this species has been found to be positively correlated with increased tree species diversity, canopy height, and percent canopy cover.
Northern populations breed in mature, moist coniferous forests.
This species constructs its pendulum nests in hanging vegetation and so it is often attracted to suspended clumps of moss or coniferous twigs that are more abundant in moist spruce bogs or hemlock swamps.
Southern populations breed in mature, moist, bottomland forest where Spanish moss is prevalent.
Outside of the breeding season, the Northern Parula becomes more of a habitat generalist and may be found in a wide variety of habitats during migration and winter.
These habitats may include: pastures; moist, dry or wet forests; and agricultural fields or plantations.