Brown-headed Cowbird bills are a very distinctive shape of being short and thick. The males have a full brown head while the females would have patches of brown.

The Brown-headed Cowbird is North America’s most common “brood parasite.” A female cowbird makes no nest of her own, but instead lays her eggs in the nests of other bird species, who then raise the young cowbirds.

Brown-headed Cowbird lay eggs in the nests of more than 220 species of birds. Recent genetic analyses have shown that most individual females specialize in one particular host species.

Cowbird eggs hatch faster than other species' eggs, giving cowbird nestlings a head start in getting food from the parents.

Dark-eyed Juncos are birds of the ground that often hop around the bases of trees and shrubs in the forests looking for fallen seeds.

A recent estimate set the junco’s total population at approximately 630 million individuals

Dark-eyed Juncos are the "snowbirds" of the middle latitudes. Over most of the eastern United States, they appear as winter sets in and then retreats northward each spring. Other juncos are year-round residents, retreating into woodlands during the breeding season, or, like those of the Appalachian Mountains, moving to higher elevations during the warmer months.

Flocks of Juncos can be found around woodland edges and suburban yards, feeding on the ground, making ticking calls as they fly up into the bushes

The large, handsome Golden-crowned sparrow is a common bird in weedy or shrubby lowlands and city edges in winter along the Pacific coast. 

This sparrow is one of the least known of our songbirds, particularly on its northern breeding grounds. It has been the subject of only a few laboratory and field studies, so most of what we know about it comes from scattered notes in scientific journals.

Miners in the Yukon at the turn of the twentieth century woefully referred to the Golden-crowned sparrow as the “no gold here” bird, because its song resembled that depressing phrase. They also interpreted its song to say “I’m so tired,” prompting them to dub the bird “Weary Willie.”

The Golden-crowned sparrow arrives earlier and stays longer on its California wintering grounds than almost any other bird species.

When the day length increases in the spring, the Golden-crowned sparrow detects the change through photoreceptors (light-sensitive cells). Its body responds by putting on fat and getting an urge to migrate.

The oldest Golden-crowned Sparrow on record was at least 10 years, 6 months old. It was caught by a bird bander in California in 1970 and released.

An American robin can produce three successful broods in one year. On average, though, only 40 percent of nests successfully produce young. Only 25 percent of those fledged young survive to November. From that point on, about half of the robins alive in any year will make it to the next. Despite the fact that a lucky robin can live to be 14 years old, the entire population turns over on average every six years.

Although robins are considered harbingers of spring, many American robins spend the whole winter in their breeding range. But because they spend more time roosting in trees and less time in your yard, you're much less likely to see them. The number of robins present in the northern parts of the range varies each year with the local conditions.

Robins often eat a lot of fruit in fall and winter. When they eat honeysuckle berries exclusively, they sometimes become intoxicated.

Robin roosts can be huge, sometimes including a quarter-million birds during winter. In summer, females sleep at their nests and males gather at roosts. As young robins become independent, they join the males. Female adults go to the roosts only after they have finished nesting.

Robins eat different types of food depending on the time of day: more earthworms in the morning and more fruit later in the day. Because the robin forages largely on lawns, it is vulnerable to pesticide poisoning and can be an important indicator of chemical pollution.

The oldest recorded American robin was 13 years and 11 months old.

The Pacific-slope flycatcher often inhabits either coniferous or deciduous forests is a insectivorous bird.

In parts of the interior Northwest, Pacific-slope Flycatchers sometimes hybridize with Cordilleran Flycatchers where their ranges meet. In this region, vocalizations also vary and can be difficult to ascribe to one species or the other.

The population of Pacific-slope Flycatchers breeding on the Channel Islands off southern California has a longer bill, a paler chest, slightly different vocalizations, and differs genetically to it’s mainland cousins.

The oldest Pacific-slope Flycatcher on record was one banded in California as a hatch-year bird in 1992 that was recovered in Oregon in 1999 when it was about 6 years, 11 months old.

The oldest recorded Spotted Towhee was a male, and at least 11 years old when he was recaught and re-released during banding operations in California in 2010.

Watch a Spotted Towhee feeding on the ground; you'll probably observe its two-footed, backward-scratching hop. This "double-scratching" is used by several towhee and sparrow species to uncover the seeds and small invertebrates they feed on. One Spotted Towhee with an unusable, injured foot was observed hopping and scratching with one foot.

The Spotted Towhee and the very similar Eastern Towhee used to be considered the same species, the Rufous-sided Towhee. The two forms still occur together in the Great Plains, where they sometimes interbreed. This is a common evolutionary pattern in North American birds – a holdover from when the great ice sheets split the continent down the middle, isolating birds into eastern and western populations that eventually became new species.

People have trained falcons for hunting for over a thousand years, and the Peregrine Falcon was always one of the most prized birds. 

Falcons nest on cliffs up to 1,300 feet high and sometimes higher.

The Peregrine Falcon is one of the most widespread birds in the world. It is found on all continents except Antarctica, and many oceanic islands.

The peregrine falcon is the world's fastest diving bird. The record-setting falcon was once clocked diving at a speed of 186 miles (300 kilometers) an hour.

The Red-winged Blackbird is a highly polygynous species, meaning males have many female mates – up to 15 in some cases.

Male Red-winged Blackbirds fiercely defend their territories during the breeding season, spending more than a quarter of daylight hours in territory defense. He chases other males out of the territory and attacks nest predators, sometimes going after much larger animals, including horses and people.

Red-winged Blackbirds roost in flocks in all months of the year. In summer small numbers roost in the wetlands where the birds breed. Winter flocks can be congregations of several million birds, including other blackbird species and starlings.

Each morning the roosts spread out, traveling as far as 50 miles to feed, then re-forming at night.

The oldest recorded Red-winged Blackbird was 15 years, 9 months old. It was banded in New Jersey in 1967, and found alive, but injured in Michigan in 1983. It was able to be released after recovering from its injuries.

White-tailed kites can hover in the air without beating their wings; this distinctive ability of kites is known as 'kiting'.

Those individuals that reach maturity can expect to live an average of 10 years. The oldest known wild kite was 26 years old.

Small mammals, especially voles, make up the majority of the White-tailed Kite's diet.

White-tailed Kites are found in open grasslands with scattered trees for nesting and perching

While hunting, the White-tailed Kite hovers up to 80 feet off the ground and then drops straight down onto prey items with talons out

The nest of the Western Meadowlark usually is partially covered by a grass roof. It may be completely open, however, or it may have a complete roof and an entrance tunnel several feet long.

Although the Western Meadowlark looks nearly identical to the Eastern Meadowlark, the two species hybridize only very rarely. Mixed pairs usually occur only at the edge of the range where few mates are available. Captive breeding experiments found that hybrid meadowlarks were fertile, but produced few eggs that hatched.

John James Audubon gave the Western Meadowlark its scientific name, Sturnella (starling-like) neglecta, claiming that most explorers and settlers who ventured west of the Mississippi after Lewis and Clark had overlooked this common bird.

In 1914, California grain growers initiated one of the earliest studies of the Western Meadowlark’s diet to determine whether the bird could be designated a pest species. Although they do eat grain, Western Meadowlarks also help limit the number of crop-damaging insects.

The Western Meadowlark is the state bird of six states: Kansas, Montana, Nebraska, North Dakota, Oregon, and Wyoming. Only the Northern Cardinal is a more popular civic symbol, edging out the meadowlark by one state.

A male Western Meadowlark usually has two mates at the same time. The females do all the incubating and brooding, and most of the feeding of the young.

The oldest recorded Western Meadowlark was at least 6 years, 6 months old when it was found in Colorado in 1965.

The turkey vulture has the largest olfactory (smelling) system of all birds.

Turkey vultures are the only scavenger birds that can't kill their prey.

Male and female turkey vultures look the same. They are the same size and have no identifying traits that would signal their sex. Gender.

Worldwide there are 23 species of vultures, 14 of which are endangered or threatened.

These birds have a cluster of overlapping feathers on top of their small heads that curl into a U shape.

They mainly eat seeds, berries, and flowers. The animals also chow down on snails and small insects like caterpillars, beetles, and millipedes.

Female California quail have brown heads. The males’ heads are black with white stripes.

Females lay white eggs with brown markings.

Barn swallows are long-distance migrants who spend their winter in parts of Central and South America, and have been found as far south as Argentina — 9,000 kilometers away!

Barn swallows build their nests with mud pellets and like to reuse nests year after year.

The birds frequently produce two broods of four or five eggs in a year, and 70 to 90 percent will successfully raise at least one young.

Young will leave the nest between 19 and 24 days after hatching.

Barn swallows live on average four years, beginning breeding at one year old

The oldest recorded barn swallow in North America was eight years old, recaptured in Maryland in the US.

The Red-tailed Hawk is one of the largest birds you'll see in North America,

They can easily be identified by the brick red tail feathers that give this bird its name.

The red-tailed hawk is a top predator

The oldest known wild Red-tailed Hawk was at least 30 years, 8 months old when it was found in Michigan in 2011, the same state where it had been banded in 1981.