The wee little brown birds that you see congregating around people dining outside are probably house sparrows (Passer domesticus). Dull in color but socially vibrant, the sparrow likes to live close to humans, and it is an opportunistic eater. But beyond cheerfully snatching bits of French fries that fall to the ground, sparrows will happily eat many other types of food.

House sparrows are stocky birds with thick bills that are about 6 1/2 inches in length. They are diurnal, meaning they are active during the day and not at night. House sparrows are sexually dimorphic, meaning the males and females look different from each other. The males are gray-headed with white cheeks and a large black mark called a bib across their chests. Their wings are black-tipped. The undersides of the males are buff in color, and their rumps and tail are gray. The females are more muted in color, mostly reddish brown. Both have brown backs with some black feathers as well. Sparrow weight and size differ slightly between the male and female. The average male sparrow weight is 28.5 grams or 1 ounce. The average female sparrow weight is 25.3 grams or 0.89 ounces.

House sparrows are not native to North America. In fact, they are Eurasian sparrows that were introduced, possibly in the 1850s. Their populations have grown well in urban areas where people live. When people moved to farms, sparrows followed. With large corporate farm development, however, sparrows dwindled in the countryside. House sparrows do not tend to live in deserts, grasslands, tropical regions or thick forests. The denser the human population is in an area, the more attractive it is to sparrows.

The name “house sparrow” describes the behavior and favored location of these little birds. They like to live where people live. They build nests on people’s houses and on manmade structures like street lamps. House sparrows like to roost in vines and other plants near human structures.

House sparrows nest in late winter or early spring in a male sparrow’s territory, which he will fiercely guard. Sometimes other kinds of birds get evicted from their nest to make room for house sparrow eggs! This negatively affects many native bird populations, such as the bluebirds and swallows whose cavities and houses are usurped. A typical sparrow nest is a messy little dome that can be made from feathers, paper, dried plants, leaves, string, sticks, grasses or any available soft materials. Sometimes the highly sociable sparrows will build nests next to each other and share walls. Females will lay up to five eggs in a clutch on average. A female can lay more eggs fairly quickly so that she has as many as four broods in a season. It is primarily the female who incubates house sparrow eggs, though the male occasionally assists. House sparrow eggs range from white to very pale green or blue with gray or brown spots, and they are just under 1 inch in length and about 0.6 inches wide. Because of the great number of house sparrow eggs laid in one year, sparrow populations are able to grow quickly. Both the mother and the father feed their young.

Sparrows do have natural predators. Ecologically, they are an important prey species for many animals. House cats are a major enemy of sparrows. Other predators include dogs, raccoons, merlins, various species of owls and Cooper’s hawks. Snakes are known to take sparrow eggs. Because sparrows are highly social animals, hanging out in groups helps protect them from predators because so many can keep watch.

Sparrows may move around a little to be warmer in winter, but they do not migrate out of an area. Sparrows can live as long as 13 years.

Sparrows like to hop along, rather than walk to find their food, usually on the ground. Sparrows are omnivores, meaning they eat a variety of foods, both plant and animal-based. The many foods in the sparrow diet depend on where the sparrow lives. The sparrow diet may consist of berries, grapes, loquats, apples, nuts, cherries, pears, plums, peaches, nectarines, tomatoes, peas, lettuce, soybeans, rice, weed seeds, grains, crumbs from bread, dropped French fries, restaurant waste, flowers, buds and oil seeds such as sunflower seeds. At fast-food restaurants, sparrows seem almost ubiquitous, ready to snatch up any little bit of dropped food from customers, or plucking their way through garbage. People seem unable to resist intentionally tossing crumbs to the birds as well. Sparrow also enjoy wild foods like crabgrass and other grasses, as well as buckwheat and ragweed. Sparrow babies are fed insects. The parents make sure to time their reproduction based on the opportunity for high insect populations to feed their young.

Not only do insects and other invertebrates make up part of the sparrow diet, but some other animals do as well. It may be hard to imagine, but sometimes even little vertebrates such as frogs and lizards can become sparrow food!

Scientists now think that sparrows adapted to human food as part of their evolutionary process. Their skull shapes changed and their bodies developed traits that helped them to break down and digest starch, much as domesticated dogs did. Sparrows changed and so did sparrow food, as a result. Perhaps most intriguing, these changes coincided with the development of human agriculture some 11,000 years ago! More research is needed to determine what other changes took place in sparrows to make them so dependent upon humans.

Because the sparrow diet is so intertwined with human food sources, sparrows can become a pest to farmers. Those sparrows that live on farms enjoy consuming the corn, wheat, oats and other grains that makeup livestock feed. Sparrows will pillage orchard crops as well. Significant grain loss can occur on farms. Unfortunately, sometimes new shoots and seedlings become sparrow food as well. Their constant chatter and large flocks (some even in thousands!) make a lot of noise and mess that can irritate farmers and other people as well. Even their feces can become a problem. Since many farmers have moved to single-crop farms, however, since the 1960s fewer sparrows have made farms their preferred homes.

Sparrows are not a pest to everyone. They are lively, social, brazen little birds that can be a joy to watch. Sparrows enjoy dining at bird feeders. A mix of seeds such as commercial birdseed makes good sparrow food. If you would like to offer a mix of seeds to attract house sparrows, try using sunflower seeds, millet or corn. Milo, or sorghum seeds, is a common ingredient in commercial mixes but may not be that appetizing to sparrows that have other choices. Offer sparrows water to drink and an area to dust-bathe, which they love to do. While sparrows will certainly find food no matter where they live without your help, watching them hop and chirp can provide a great deal of entertainment. Sparrows, known for their chipper and seemingly friendly dispositions, have even been referenced in poetry in many cultures.

Sparrows can be found nearly everywhere. In fact, the only continent without any sparrow populations is Antarctica. In some ways their adaptability rivals the humans whose food they love! It is fascinating to think that wherever humans have ventured and settled, eventually sparrows have followed.