Photo donated by Danny Brown

Photo of Baltimore Oriole by Hagit Berkovich

Goldfinches are among the strictest vegetarians in the bird world, selecting an entirely vegetable diet and only inadvertently swallowing an occasional insect. (Photo: Michael Henry)

Though almost entirely herbivorous, eating a wide variety of plants, white-tailed deer have been known to opportunistically feed on nesting songbirds and field mice. (Photo: Trish Satkofsky)

Unlike the larvae that only eat milkweed, adult monarchs feed on a wide variety of nectar bearing flowers. They will visit many different kinds of flowers in their search for food. (Photo: Dave Hawkins)

Cottontails feed mainly on herbaceous plants such as clovers, grasses, and low broad-leafed weeds in summer, and buds, twigs, and bark in winter. (Photo: Chuanxiao Li)

Eastern lubbers, like most all grasshoppers, can regurgitate recently consumed plant material. This regurgitant is mostly liquid and has a dark brown color and is commonly referred to as ‘tobacco spit.’ (Photo: Pamela Wanamaker)

On very rare occasions, when its usual plant food sources are scarce, Eastern gray squirrels will prey upon insects, frogs, small rodents, and small birds, their eggs and young. (Photo: Colleen Faupel)

The red pigment in the face of the Western Tanager is rhodoxanthin, a pigment rare in birds. It is not manufactured by the bird, as are the pigments used by the other red tanagers. Instead, it must be acquired from the diet, presumably from insects that themselves acquire the pigment from plants. (Photo: Jim Brown)

Aspen has been traditionally reputed in many countries to drive off evil spirits, hence it was often planted near dwellings. (Photo: Chad Martens)

The average clutch size of the Cape May Warbler (six) is greater than that of other warblers. This large clutch size may allow Cape May Warbler populations to expand rapidly during outbreaks of their preferred prey, spruce budworms. (Photo: Michael Henry)

The jumping spider family contains more than 500 described genera and about 5,000 described species,making it the largest family of spiderswith about 13% of all species. (Photo: Jeffery Waldorff)

Goldfinches are among the strictest vegetarians in the bird world, selecting an entirely vegetable diet and only inadvertently swallowing an occasional insect. (Photo: Christine Adachi)

A Monarch caterpillar can eat enough milkweed in one day to equal its own body weight. Just 9 to 14 days after hatching from its eggs, a caterpillar will grow to about 2 inches long. (Photo: Andrew Halverson)

Life can be dangerous for a small bird. Yellow Warblers have occasionally been found caught in the strands of an orb weaver spider’s web. (Photo: Steven Manly)

There are more than 550 species of swallowtail butterflies around the word. Altough the majority are tropical, members of the family are found on all continents except Antarctica. (Photo: Marty Bays)

Goldenrod is often unfairly blamed for causing hay fever in humans. The pollen causing these allergies is mainly produced by ragweed which blooms at the same time as goldenrod but is wind-pollinated. Goldenrod pollen is too heavy and sticky to be blown far from the flowers, so is mainly pollinated by insects. (Photo: Weg Thomas)

The Black-Eyed Susan has been the official flower of Maryland since 1918 when it was designated the "Floral Emblem" of Maryland by the General Assembly. (Photo: Marvin De Jong)

Like all other blue birds, Indigo Buntings lack blue pigment. Their jewel-like color comes instead from microscopic structures in the feathers that refract and reflect blue light, much like the airborne particles that cause the sky to look blue. (Photo: Steve Creek)

Bluebells have smooth gray-green foliage and nodding clusters of pink buds that open into light blue trumpet-shaped flowers. When they grow in masses, bluebells make a spectacular show. (Photo: Sandra Brooks-Mathers)

Outside of the breeding season the Tree Swallow congregates into enormous flocks and night roosts, sometimes numbering in the hundreds of thousands. They gather about an hour before sunset at a roost site, forming a dense cloud. (Photo: Paul Lackey)

Eastern Bluebirds typically have more than one successful brood per year. Young produced in early nests usually leave their parents in summer, but young from later nests frequently stay with their parents over the winter. (Photo: James Alligood)

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. (Photo: Laura Epps)

The Spicebush Swallowtail is a common black swallowtail butterfly found in North America, also known as the Green-Clouded butterfly. The swallowtails are unique in that even while feeding, they continue to flutter their wings. (Photo: Joyce Walton)

Despite their impressive size, Great Blue Herons weigh only 5 to 6 pounds thanks in part to their hollow bones—a feature all birds share. The oldest Great Blue Heron, based on banding recovery, was 24 years old. (Photo: Steve Duffey)

The Blue Dasher is a dragonfly of the skimmer family. It is common and widely distributed in the United States. Although the species name P. longipennis means "long wings", the wings are not particularly long. (Photo: Bill Houghton)

Steller’s Jays have the dubious honor of being one of the most frequently misspelled names in all of bird watching. Up close, the bird’s dazzling mix of azure and blue is certainly stellar, but that’s not how you spell their name. (Photo: Lori Zappas)

A striking black-winged red bird, the Scarlet Tanager is a common species of the eastern forest interior. Despite its brilliant coloring it is often overlooked because of its rather secretive behavior and its preference for the forest canopy. (Photo: Daniel Marquis)

Ladybugs are favored by farmers as voracious pest-eaters. By the end of its three-to-six-week life, a ladybug may eat 5,000 plant-eating insects. (Photo: David Bahr)

The red of a male House Finch comes from pigments contained in its food during molt. So the more pigment in the food, the redder the male. Females prefer to mate with the reddest male they can find, perhaps raising the chances they get a capable mate who can do his part in feeding the nestlings. (Photo: Gregory Fisher)

The Pileated Woodpecker is one of the biggest, most striking forest birds on the continent. They dig characteristically rectangular holes in trees to find ants. These excavations can be so broad and deep that they can cause small trees to break in half. (Photo: Hal and Kirstin Snyder)

The strikingly colored juvenile stage (terrestrial) of the Red Spotted Newt is followed by the olive-green colored adult stage (aquatic). They have a lifespan of 12 to 15 years in the wild, and may grow to 5 inches in length. (Photo: John Kornet)

Although relatively common, overpicking this handsome wildflower has resulted in its scarcity in some areas. Since most insects find it difficult to navigate the long tubular flowers, Cardinal Flower depends on hummingbirds, which feed on the nectar, for pollination. (Photo: Paul Lackey)

A distinctive songbird of arid scrublands, the Pyrrhuloxia lives in the southwestern United States and northern Mexico. It superficially resembles its close relative, the Northern Cardinal. Foraging winter flocks of Pyrrhuloxias may number as many as 1,000 birds. (Photo: Daniel Ruf)

The male Rose-breasted Grosbeak participates in incubation of the eggs, accounting for about 1/3 of the time during the day (the female incubates over night). Both sexes sing quietly to each other when they exchange places. (Photo: Lori Deiter)

Only a few female North American songbirds sing, but the female Northern Cardinal does, and often while sitting on the nest. This may give the male information about when to bring food to the nest. Cardinals don’t migrate or molt into a dull plumage. (Photo: Stan Lewis)

Photographer: Kelly Lyon   Location: Boulder, CO

Photographer: Howard Witkin   Location: Boulder, CO

Photographer: Dan Walters   Location: Wheat Ridge, CO

Photographer: Nil Eren   Location: Barrow, AK

Photographer: Donna Carr Location: Pribilofs, AK

Photographer: Ryan Weishalla Location: Leroy, IL

Photographer: William Wiley Location: South of Lincoln, NE

Photographer: Suzanne Rogers Location: Fort Wayne IN

Photographer: Jim Brown   Location: Shirley Basin, WY

Photographer: Sandra J. Brierley Location: Grand Teton National Park