Special features

Exceptional immigrant

140 years after its introduction in North America, pleasant, understated Eurasian Tree Sparrow continues to win fans and attract birders
By Ted Cable | Published: 12/22/2011

BRD-A0212-500With great anticipation, I walked out of the lobby of the Jingshi Hotel and into the hazy light of a Beijing morning. Like most birders on business, I had my binoculars in my briefcase and was anxious to pull them out at the sight of my first Chinese bird.

I immediately headed for trees on the surprisingly wooded campus of Beijing Normal University, walking past scores of elderly individuals striking odd poses and doing slow-motion movements of Tai Chi. Students on park benches recited their lessons out loud, creating a strange soft murmur that drifted across the campus. Just before reaching my destination, I saw them — sparrows on the sidewalk.

To my surprise, they were Eurasian Tree Sparrows. I had last seen the species at a nondescript grain elevator in western Illinois 30 years ago. Although they weren’t Azure-winged Magpies or some other exotic Chinese species, it was satisfying to be reacquainted with these pleasant birds. I was struck by their petite and dapper appearance.

Over the next few days, I discovered that the sparrow was probably the most abundant bird in Beijing. Eurasian Tree Sparrows were on rooftops and window sills. They clustered beneath melon vendors’ carts on street corners and cleaned crumbs off of Tiananmen Square.

Again, like most birders on business, during my morning meeting, my mind wandered. I wondered how the sparrow could be abundant throughout this modern city yet absent in Chicago, New York, and other North American cities. Recalling that Eugene Schieffelin and his Shakespeare-loving group attempted to introduce every bird the Bard had ever mentioned but only the starling had become established, I wondered why Eurasian Tree Sparrow seemed to be the exception to the boom-or-bust nature of non-native introduction attempts. Why did the closely related House Sparrow spread across the continent, whereas the Eurasian Tree Sparrow spread only as far as western Illinois, eastern Missouri, and southeastern Iowa? I needed to learn more about this understated species.

A German import
The story of its North American establishment begins early in 1870, when a St. Louis bird dealer imported a shipment of birds from Germany. Among them were about 20 Eurasian Tree Sparrows. (Published accounts in 20th-century reference works range from 12 to 24, while the earliest 19th-century reference refers to 20 birds.)

Word of the shipment spread through the close-knit German community. A Mr. Kleinschmidt convinced Carl Daenzer, founder of the Westliche Post and editor of the Anzeiger des Westens, two German-language newspapers in St. Louis, to help purchase the birds. Daenzer had been experimenting with releasing European songbirds in the growing St. Louis immigrant neighborhoods. On April 25, 1870, a damp, chilly, overcast day, Daenzer carried his box of birds to 30-acre Lafayette Park. Established in 1836 as St. Louis’s first park, it already had mature trees and shrubs and so appeared to provide appropriate habitat.

As the sparrows winged their way up into the gray American airspace, “horse cars” (streetcars pulled by horses) clip-clopped around the park’s perimeter, horse-drawn carriages leisurely carried people through the park, and men on horse-drawn wagons delivered products throughout the affluent adjacent neighborhood. Such equestrian traffic would play a role in providing food for the sparrows in the form of spilled grain. If the birds had lingered, they would have been joined by hundreds and at times even thousands of Victorian park visitors, listening to concerts, strolling the paths, or gliding across the largest pond in boats modeled after another European avian immigrant, the Mute Swan. But the Eurasian Tree Sparrows did not linger; they flew out of sight immediately.

This rendering shows Lafayette Park in St. Louis as it appeared in the 1870s, when Carl Daenzer released the Eurasian Tree Sparrow in it.

This rendering shows Lafayette Park in St. Louis as it appeared in the 1870s, when Carl Daenzer released the Eurasian Tree Sparrow in it.

PUBLIC AREAS WITH EURASIAN TREE SPARROWS

Horseshoe Lake State Park 
Granite City, Illinois

Frank Holten State Park
East St. Louis, Illinois

Two Rivers National Wildlife Refuge
Brussels, Illinois

Corps of Engineers Riverlands Migratory Bird Sanctuary
West Alton, Missouri

North Riverfront Park
St. Louis, Missouri

Columbia Bottom Conservation Area
St. Louis, Missouri

Clarence Cannon National Wildlife Refuge 
Annada, Missouri

St. Stanislaus Conservation Area 
Florissant, Missouri

Ulysses S. Grant Trail
Clayton, Missouri

For directions to these and other locations, see the book Birds of the St. Louis Area: Where and When to Find Them ($15), available from the Webster Groves Nature Study Society, P.O. Box 190065, St. Louis, MO 63119-6065.

Nostalgia and pride
If you have ever lived far from home and missed your “home birds,” you can relate to the motives of Daenzer and other 19th-century German immigrants. They longed for the sights and sounds of familiar birds from the Old Country, and their sentimentality and nostalgia may have been flavored with a touch of nationalistic pride. Other European birds such as European Goldfinches, Eurasian Bullfinches, Chaffinches, Greenfinches, and Linnets were also set free in Lafayette Park. Accounts indicate that the European immigrants found the diversity of the local avifauna to be lacking and wanted to supplement it.

Months passed without any Eurasian Tree Sparrow sightings, so the keenly interested public assumed the sparrow’s introduction, like that of the various European finches, had failed. Then, on April 24, 1871, one day short of the anniversary of their release, one was seen a mile east of the park. The sighting was considered newsworthy, and articles about it appeared in the local press. By that summer, just 14 months after the initial release, Eurasian Tree Sparrows could be found in many locations throughout the city.

Conditions were favorable for these German avian immigrants. Neither the House Sparrow nor the starling had yet arrived in St. Louis, so Eurasian Tree Sparrows did not face competition from other nonnative birds for nesting cavities.

The newcomers also took advantage of another link to their homeland: They fed on the grain that was spilled around Anheuser-Busch and other early breweries established by German immigrants. Because of the birds’ ancestry and strong association with the local German community, they were called German Sparrows, much like House Sparrows were once called English Sparrows.

In 1876, the U.S. Army surgeon and early ornithologist Dr. James C. Merrill spent time in the city of St. Louis and found Eurasian Tree Sparrows to be “abundant.” He wrote, “In St. Louis it considerably outnumbers P. domestica [House Sparrow], and as is the case in Europe, it prefers the outskirts of the city and the country.”

More sparrows were released in 1879 to supplement the expanding population and possibly to level the competition with newly arrived House Sparrows, which had been released in the mid-1870s. Dr. C. Hart Merriam, the first chief of the Division of Economic Ornithology and Mammalogy of the U.S. Department of Agriculture, also reported that in New York City, Eugene Schieffelin of starling-release infamy found 50 or 60 Eurasian Tree Sparrows in the store of a bird importer.

The species continued to be imported as cage birds into the 1920s and presumably were released in many North American locations along with other European songbirds, but their establishment apparently was foiled by pre-­existing populations of House Sparrows.

Tornados and steamships
In 1896, a tornado went through Lafayette Park and destroyed all of the buildings and almost all of the trees. Undoubtedly, any Eurasian Tree Sparrow colonies would have been wiped out. Whether the sparrows returned to Lafayette Park is unknown, but by then they had spread to outlying areas of the city. They may have even hitched rides on the scores of paddlewheel steamships plying up and down the Mississippi River. Sparrows that ended up in Paducah, Kentucky, were assumed to have arrived by steamship.

By 1928, Eurasian Tree Sparrows had become established eastward into the Illinois towns of Alton, Grafton, and Belleville and westward to Washington County, Missouri. As their close relative, the more aggressive House Sparrow, became more abundant, it began to force the Eurasian Tree Sparrow from many of its urban nesting areas.

From the beginning, folks distinguished between introduced and native species, and by all accounts, they welcomed the Eurasian Tree Sparrow into their neighborhoods. For example, Dr. Merriam, acting on his desire for the population to grow, waited to collect four specimens until the breeding season had been completed. Even in the 1870s, people were putting up nest boxes for the sparrow.

House Sparrows soon drove the Eurasian Tree Sparrows out of many of their initial nest sites and any nest box with a hole big enough to accommodate the larger House Sparrow. Local people almost immediately considered House Sparrows pests. Missouri’s earliest birder, Otto Widmann, documented the spread of Eurasian Tree Sparrows and House Sparrows through the late 1800s in the St. Louis area. “This Tree Sparrow,” he opined, “is a much more acceptable acquisition than the House Sparrow…. it lacks the fighting qualities for which the other is so much hated…. it enjoys the company of our native birds, and is daily seen associating with our winter Junco and Canadian [American] Tree Sparrow.”

In 1888, after witnessing House Sparrows displace native birds, he wrote: “About the bad qualities of the imported Sparrow nothing new can be said… I have been living in war with the House Sparrow since its appearance.”

The general public seems to have shared his views. In an 1882 article in the St. Louis Post-Dispatch newspaper about a hail storm that killed hundreds of birds, the reporter writes: “The boys in the neighborhood of Lafayette Park have gathered fully a basket full of dead birds, principally robins. Several thrushes and only one dead sparrow were found. The vitality of the piratical sparrows carried them through the aerial fusillade unhurt — a fact which every lover of our home birds will sincerely deplore.” Clearly, this newspaper reporter favored “home birds” over the “piratical sparrows.”

Today, Eurasian Tree Sparrows do not nest in Lafayette Park or the other urban parks where they once resided. Instead, they are limited to residential neighborhoods with mature trees and older homes, where they sometimes nest in the eaves.

EQUALLY EXCEPTIONAL: EUROPEAN GOLDFINCH 

Think a European bird could become established in North America only in the 19th century? Think again.

According to Contributing Editor Julie Craves, European ­Goldfinch appears to be well on its way to becoming established in the western Great Lakes area right now.

Craves analyzed more than 400 reports of goldfinches in 20 states and five provinces from January 2002 through June 2006 and discovered not only a clear concentration of reports from northeastern Illinois and southeastern Wisconsin but evidence that the birds are nesting.

Plenty of rural habitat is available, and the bird’s preferred foods — the seeds of composites and non-native weeds such as knapweeds, teasels, and burdocks — are widespread.

“Considering the eventual extirpation of quite long-­established populations in New York in the early 1900s,” Craves writes, “the persistence of the Illinois and Wisconsin birds hardly seems assured.” But two factors might make a difference: the sheer number of goldfinches in the region, and the fact that the population is apparently being augmented by goldfinches being released by a bird importer in the Chicago area.

Craves is supervisor of avian research at the Rouge River Bird Observatory at the University of Michigan Dearborn and writes our regular column “Since You Asked.” She published her findings in North American Birds in 2008.

Where to find sparrows
Outside the city, their primary range extends northeast along the Illinois River and its major tributaries, such as the Sangamon River, to central Illinois. The birds can also be found in smaller numbers north along the Mississippi to eastern Iowa and west along the Missouri River to the edge of the St. Louis metropolitan area. Just as they took advantage of the grain around the early breweries, their current range may be influenced by the concentration and availability of the grain grown and stored in the fertile flood plains and the grain spilled as it is loaded on trains or barges for export.

Most extralimital sightings in North America are reported in winter and north of their current breeding range. This is particularly interesting because, in Europe, the sparrows move southward during severe winters. Eurasian Tree Sparrows have wandered to Indiana, Michigan, Kentucky, Minnesota, Wisconsin, Manitoba, and Ontario. Closer to their home, they have been seen in the Chicago area and in Missouri at feeders in such locales as Columbia, Lake of the Ozarks, and Cape Girardeau. Sparrows have also been found in British Columbia and Oregon. These probably arrived by ship or escaped from cages much like the original birds released in St. Louis, only in these cases their arrival was accidental.

Although the species seems less likely to wander during the breeding season, Brad Jacobs, a wildlife ecologist with the Missouri Department of Conservation, reports that Eurasian Tree Sparrows have nested in bluebird boxes in at least two locations in Boone County in central Missouri.

Why have the sparrows not spread much in the past 140 years? Competition with the bigger, bolder House Sparrows seems to be the most likely answer.

In 1909, Otto Widmann wrote the following: “But in the meantime their larger cousins, the House Sparrows, which made their original start from the center of town and had become more and more abundant, began to invade the domain of the European Tree Sparrows, driving them out of their nesting and roosting places, thereby forcing them farther and farther toward the outskirts of the city.”

Other as-yet-unknown factors may limit Eurasian Tree Sparrow expansion, but competition with House Sparrows is surely important. Today in Germany, the House Sparrow is dominant, and ancestors of our Eurasian Tree Sparrows select nesting habitats where the House Sparrow is absent. In Germany during summer, Eurasian Tree Sparrows are mostly rural, being common birds of farmland and orchards. In fact, the German name for the species is the compound noun Feld­sperling, which means “field sparrow.”

However, in cities without a House Sparrow population or with only newly established populations, Eurasian Tree Sparrows breed in and around buildings. This explanation explains the abundance I observed in China. House Sparrows are absent throughout most of the country, so their role is filled by Eurasian Tree Sparrows: nesting in eaves at Beijing’s Summer Palace and niches along the Great Wall.

Eurasian Tree Sparrows are local and uncommon throughout their limited North American range. You can spend a whole day birding in St. Louis, west-­central Illinois, or southeastern Iowa without seeing one unless you make a special effort to visit a place where they are known to occur.

With a few exceptions, they are most common in the floodplains of the Mississippi, Missouri, and Illinois Rivers, rather than in upland areas. In these bottomlands, the sparrows are more often seen in trees, and less frequently seen on buildings, than House Sparrows. Jacobs recommends looking for them at the grain elevators along the major rivers or at the edges of towns in bushes near a farm house.

Pride of St. Louis
In St. Louis, during the breeding season, Eurasian Tree Sparrows can be found most easily in neighborhoods such as Dogtown and The Hill southwest of the expansive and historic Forest Park but, curiously, not in Forest Park itself. You can also find the sparrows at several public areas, particularly in winter.

In winter, Eurasian Tree Sparrows become feeder birds and mingle with House Sparrows. In rural areas, flocks of 50 or more Eurasian Tree Sparrows can be found in hedgerows or brush piles, especially near water. In fact, Christmas Bird Count participants often find the sparrow in the same open habitats as the American Tree Sparrow.

Birders have found that the most difficult time to find Eurasian Tree Sparrows is between August and November, when the birds are finished nesting but not yet coming to feeders. They tend to wander and disappear from predictable locations during these months.

Whereas the House Sparrow may suffer from “familiarity breeding contempt,” Eurasian Tree Sparrows’ lack of aggression (authors have called them “timid” and “meek”) and limited range generate benevolence and interest. Most St. Louis birders take pride in the fact that people come from all over North America to add the species to their lists, and many residents put up nest boxes in their yards, just as Widmann did in the 1880s.

The sparrow’s social nature means that colonies can be established in a single yard. Birder Mike Flieg has had as many as 10 boxes occupied by Eurasian Tree Sparrows in his backyard (although he has a friend who has 20 boxes being used in his yard). Nest boxes have the dimensions of Eastern Bluebird boxes and 1⅛-inch (29mm) entrance holes to exclude the larger House Sparrows. Under such ideal conditions where Eurasian Tree Sparrow colonies exist as a group, they can be quite aggressive, and they hold their own against incursions by House Sparrows.

For many years, Flieg hosted visiting birders who arrived almost weekly. Some of the birders he helped flew into St. Louis specifically to see the bird. Flieg lived near that airport. Before the days of airport security, if birders had a two-hour layover in St. Louis, he could pick them up, show them the Eurasian Tree Sparrow, and get them back in time for their next flight.

Others sought the Eurasian Tree Sparrow while traveling to other destinations. St. Louis is noteworthy for the confluence of not only great rivers but great highways. Interstates 55, 44, 70, and 64 all intersect in the city, bringing birders from all directions. Many stop off to tick the Eurasian Tree Sparrow.

Within its limited North American range, the sparrow is second only to St. Louis Cardinals in terms of popular local birds. Whether an Old World avian curiosity, a tick on a list, a matter of civic pride, or a reminder of birding in Beijing, this benevolent bird is enjoyed by most of us who ourselves have descended from immigrants and are not native here.

Ted Cable is a professor of interpretation and natural resource conservation at Kansas State University. He wrote about birding the grasslands of Morton County, Kansas, in our June 2002 issue, and he profiled the Chimney Swift in February 2003.