trees include eastern redbud, serviceberry, and flowering dogwood. Riparian areas are forested with mainly American sycamore. Most of the residential areas of the city are planted with large native shade trees. The largest native forest area is found in Forest Park. In autumn, the changing color of the trees is notable. Most species here are typical of the eastern woodland, although numerous decorative non-native species are found. The most notable invasive species is Japanese honeysuckle, which officials are trying to manage because of its damage to native trees. It is removed from some parks. Large mammals found in the city include urbanized coyotes and white-tailed deer. Eastern gray squirrel, cottontail rabbit, and other rodents are abundant, as well as the nocturnal Virginia opossum. Large bird species are abundant in parks and include Canada goose, mallard duck, as well as shorebirds, including the great egret and great blue heron. Gulls are common along the Mississippi River; these species follow barge traffic. Winter populations of bald eagles are found along the Mississippi River around the Chain of Rocks Bridge. The city is on the Mississippi Flyway, used by migrating birds, and has a large variety of small bird species, common to the eastern US. The Eurasian tree sparrow, an introduced species, is limited in North America to the counties surrounding St. Louis. The city has special sites for birdwatching of migratory species, including Tower Grove Park. Frogs are found in the springtime, especially after extensive wet periods. Common species include the American toad and species of chorus frogs called spring peepers, which are found in nearly every pond. Some years have outbreaks of cicadas or ladybugs. Mosquitoes, no-see-ums, and houseflies are common insect nuisances, especially in July and August; because of this, windows are almost always fitted with screens. Invasive populations of honeybees have declined in recent years. Numerous native species of pollinator insects have recovered to fill their ecological niche, and armadillos are seen throughout the St. Louis area. Demographics St. Louis grew slowly until the American Civil War, when industrialization and immigration sparked a boom. Mid-19th century immigrants included many Irish and Germans; later there were immigrants from southern and eastern Europe. In the early 20th century, African American and white migrants came from the South; the former as part of the Great Migration out of rural areas of the Deep South. Many came from Mississippi and Arkansas. After years