Nearly every waking minute, bird songs fill the air from a well-manicured Japanese barberry hedgerow bordering Camden’s Harbor Park. Most downtown pedestrians don’t notice the birds or their persistent cheery songs. The nondescript brown birds are house sparrows, common and easily overlooked. However, their journey to Camden and every town in the United States is one of the most remarkable and controversial stories in the natural world.

Native to Europe, eight pairs of house sparrows were released in Brooklyn in 1851, allegedly by an English woman living in New York City. She did so to surround herself with birds she loved as a child in London. The eight pairs died before breeding. In 1852, 25 pairs of sparrows were released along New York City’s East River. The following year, an additional 100 pairs were introduced in Greenwood Cemetery and Central Park. As their population grew, house sparrows were introduced to Portland in 1854 and 1858.

According to late 1800s naturalists, releasing house sparrows had become an American fad. Sparrow breeders sprang up to supply urbanites with a seemingly endless supply of birds. House sparrows prospered in American cities in the late 1800s and early 1900s. Livestock and poultry feed, indigestible grain in horse droppings, and general garbage, in close proximity to vast grain fields surrounding the cities, proved perfect feeding and breeding grounds for the species. In 1915, a federal government report stated, "Countless private citizens are contributing to the spread of house sparrows by trapping acclimated birds and releasing them for enjoyment and to control insect pests in Texas, Ohio, Utah, Missouri and Georgia.”

By 1875, house sparrows were breeding in San Francisco.

In the early 1900s, pioneering birds from San Francisco and mid-western cities established sparrow populations in towns scattered along the Rocky Mountains. Today, continental house sparrow populations are estimated at 150 million birds. They are the world’s most abundant songbird and can be found on every continent except Antarctica. The species is common across Europe, most of North America, much of South America, parts of Australia, New Zealand and Hawaii.

House sparrows thrive in most places with houses and other buildings, along with two other introduced species, the European starling and the rock pigeon. The sparrow’s close association with people makes them easy to overlook.

Many birders abhor the tenacious bird because some evict blue birds, tree swallows and other native species from nest boxes and tree cavities. House sparrows, with their ability to live intimately with us, are as resourceful as humans. I recall the moment my disdain of house sparrows changed to unabashed admiration. While birding in Tucson, Az., I met a fellow birder in a hotel bar the night before my early morning return flight to Maine. She gave me detailed directions to a large saguaro cactus where a pair of elf owls had been seen.

In darkness the following morning, I drove 20 miles north of Tucson to Saguaro National Park. With the aid of my Petzl headlamp, I read the hand-written directions on a bar napkin and arrived at a 30-foot tall saguaro cactus minutes before sunrise. Peering through binoculars, I stared up at a cavity where the owl had reportedly been seen. As the sun lit up the top half of a brilliant green, spiny saguaro cactus, a bird appeared at the edge of a cavity. My heart pounded with false excitement. Instead of being treated to my first ever elf owl sighting, a house sparrow stared back at me. It was a fleeting moment of disappointment. The irrepressible house sparrow proved why it has earned the title of the world’s most successful songbird. For a species that nests in North Dakota wheat silos, Chicago street light poles, Arizona saguaro cacti, and mine shafts of England, how could the bird not be endearing?

Flocks of house sparrows have pecking orders similar to barnyard chickens. Males with large black throat patches are older and more dominant over males with less black. On several occasions, while staring into the barberry thicket near Camden’s Civil War statue, I’ve been asked, “What are you watching?”

My answer, “I’m looking for male house sparrows with the largest black bibs,” is greeted with stunned silence.

The next time you’re near Harbor Park, pause to watch and listen to a highly social bird that was not here when Camden was incorporated in 1791. You’ll walk away with the sweet sounds of their songs reverberating in your ears and heart. More importantly, you’ll be able to offer a better answer when someone asks, “What are you watching?”

Camden is a retired Maine wildlife biologist and a deer hunter.

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