Wild About Illinois Birds

Weaver finches of Illinois are the house sparrow and Eurasian tree sparrow. These two species are not native to North America and compete with native birds for nesting sites and food. The 23 species depicted on the poster were selected by Dr. Jeff Walk of The Nature Conservancy.

Order Passeriformes - These are birds with adaptations for holding on to thin twigs or stems. Three of the toes on each foot face forward and one backward to help it grasp and balance on small branches.
Family Passeridae (Old World Sparrows) - These "Old World" sparrows are small birds with a short tail and a thick beak. They have a more pronounced ridge on their bill than native sparrows of the Family Passerellidae, an extra bone in their tongue and a vestigial outer primary feather. Both Passeridae species residing in Illinois are not native to North America. See the "Conservation" section for more information.
     house sparrow (Passer domesticus) [nonnative]
     Eurasian tree sparrow (Passer montanus) [nonnative]

Family Calcariidae (Longspurs and Snow Bunting) - There are only six species of these birds in the world. While outwardly similar to the members of the Family Emberizidae in which they were previously classified, these birds were recently found to have DNA structures distinctively different from sparrows and were placed in their own family taxonomically.
     Lapland longspur (Calcarius lapponicus)
     Smith’s longspur (Calcarius pictus)
     snow bunting (Plectrophenax nivalis)

Family Passerellidae (New World Sparrows) - The sparrows, juncos and towhees belong to this family of small songbirds. They feed mainly on seeds and have a short, stout, cone-shaped beak. Species in this group are associated with woodland, grassland and aquatic habitats. The taxonomic relationships within this family are not well understood.
     grasshopper sparrow (Ammodramus savannarum)
     lark sparrow (Chondestes grammacus)
     lark bunting (Calamospiza melanocorys) *
     chipping sparrow (Spizella passerina)
     clay-colored sparrow (Spizella pallida) *
     field sparrow (Spizella pusilla)
     fox sparrow (Passerella iliaca)
     American tree sparrow (Spizelloides arborea)
     dark-eyed junco (Junco hyemalis)
     white-crowned sparrow (Zonotrichia leucophrys)
     golden-crowned sparrow (Zonotrichia atricapilla) *
     Harris’s sparrow (Zonotrichia querula) *
     white-throated sparrow (Zonotrichia albicollis)
     vesper sparrow (Pooecetes gramineus)
     Le Conte’s sparrow (Ammospiza leconteii)
     Nelson’s sparrow (Ammospiza nelsoni)
     Henslow’s sparrow (Centronyx henslowii)
     savannah sparrow (Passerculus sandwichensis)
     song sparrow (Melospiza melodia)
     Lincoln’s sparrow (Melospiza lincolnii)
     swamp sparrow (Melospiza georgiana)
     spotted towhee (Pipilo maculatus) *
     eastern towhee (Pipilo erythrophthalmus)

* This species not represented on the poster.

No sparrow or longspur species are listed as endangered or threatened in Illinois. While that news is good, it does not mean that their populations do not face challenges.

Two of the species depicted on this poster, the house sparrow and Eurasian tree sparrow, are exotic, invasive species. Until the mid- to late-1800s, these species did not exist as wild populations in North America. A small number of house sparrows from Europe were originally released in New York City in the mid-1800s and in other states soon afterward. The species can occupy almost any habitat except dense forest, they produce more than one brood per year and, with no natural predators, the population spread tremendously. House sparrows are extremely common birds in Illinois. A few Eurasian tree sparrows were released in St. Louis, Missouri, in 1870. They established a population but were displaced from the city by the arrival of the house sparrow. They adapted to other habitats and now can be found in Illinois, Missouri and Iowa. In Illinois, the Eurasian tree sparrow lives in the west central portion of the state. Both species have similar nesting requirements. They nest in cavities or partially enclosed spaces, including natural and human-made objects. They are aggressive and often take over nesting spaces used by native birds. When these species are in competition for nesting spaces with each other, the house sparrow generally wins. It may be one reason that the Eurasian tree sparrow's population in the United States has not spread widely. The huge number of house sparrows in the state reduces available food for native species, too.

Many native sparrows in Illinois are targets for nest parasitism by the brown-headed cowbird (Molothrus ater). Affected species include the eastern towhee, chipping sparrow, field sparrow, vesper sparrow and song sparrow. Brood parasites are birds that lay their eggs in the nests of other birds (host species). The parasite's eggs hatch and are raised by the host species. The brown-headed cowbird is the most common nest parasite in North America. Many of the host species that co-evolved with brood parasites have reduced the success of parasites through strategies such as building a new nest or pushing the parasite eggs out of the nest. However, if a host species has not co-evolved with a parasitic species, the host may not be able to cope with parasitism. The brown-headed cowbird, prior to European settlement, was found in the western part of our country in open grassland. It followed American bison (Bison bison) herds, eating insects from their dung and from the prairie disturbed by their hooves. Because it followed the herd it could not incubate its own eggs and raise its young, so cowbirds adapted by using the nests and parenting abilities of other birds. Because the host parent birds are attending to the parasite young, often few or none of the host's own young survive. Young cowbirds tend to hatch and develop more quickly than most songbirds’ young. Often they are bigger too, and they may push others out of the nest. With settlement and the subsequent deforestation of large areas of eastern North America, the range of the cowbird expanded greatly, negatively impacting a variety of native bird species.

Native sparrow populations have fluctuated over time based on available habitat. When grassland and open habitats expand, those species associated with them may be more successful while those species associated with more wooded habitats will decline. When wooded habitats increase, species associated with them increase, and species found in open lands may decline. A good balance of a variety of habitat types is required to maintain a healthy biodiversity. Changes in habitat availability are normally due to human actions.

​More information about Illinois wood-warblers is available from the Illinois Department of Natural Resources (IDNR). The Division of Natural Heritage manages and monitors bird populations. Natural Heritage personnel also provide assistance to landowners regarding establishing and maintaining bird habitat. The IDNR Division of Education provides supplemental resources for educators to use, including the Illinois Common Birds activity book, (click here for the Spanish version), Illinois Birds resources trunk that is available for loan from more than 70 lending locations statewide, Field Trip Packs for early childhood educators and the Biodiversity of Illinois search page lists more than 1,000 species in the state. Wood Projects for Illinois Wildlife is an IDNR booklet that includes plans for nesting boxes that are used by some warblers. Publications are available through the publications page.

The Illinois Audubon Society’s mission is to promote the perpetuation and appreciation of the native flora and fauna of Illinois and the habitats that support them. Fundamental to this end are the control of pollution, the conservation of energy and all natural resources, a sound ecological relationship between human populations and their environments and the education and involvement of the public in such efforts.