Yesterday, secretary of the interior Ken Salazar released the country’s first ever State of the Birds Report, providing a sweeping overview of the status of America’s native bird populations and the factors influencing their numbers and well-being. While the online summary did not give a state-by-state breakdown, it did provide information by habitat type, and the section on urban birds had much that applies to the Twin Cities.

The report singled out Hawaii as having the most endangered bird populations, due to both habitat destruction and competiton from exotic species. The most improved bird species are those that occupy wetland habitats, due to successful efforts to preserve and restore wetlands around the country.

On urban birds, the report acknowledged the obvious, that the most ubiquitous birds in cities are the exotic species, such as rock pigeons, house sparrows, and starlings. But, many species of native birds have adapted well to urban environments, either due to abundant food sources (garbage, feeders) or efforts to protect and reintroduce them (peregrines), as well as the ban on DDT, which took effect in 1972.

Urban examples from the report:
• Robins thrive in lawns with lots of earthworms.
• Gulls, vultures and crows find plenty of food at garbage dumps and along roadsides (roadkill).
• Hummingbirds, chickadees, native sparrows, finches, woodpeckers and others take advantage of feeders.
• “Even hawks and owls find increasingly safe nesting sites and abundant prey in our towns and cities.”

Based on 117 species of native birds that dwell in cities and suburbs, the overall trend is positive, with combined populations at 114 percent of 1968 levels. Those birds that do best in urban environments are year-round residents, probably due to “higher overwinter survival,” says the report. However, migratory birds have declined in numbers, due to the hazards of migration in general, and specific conditions created by cities, like tall buildings and confusing outdoor lighting. Some of the birds that are found in cities and have declined in numbers include common nighthawk, chimney swift, and wood thrush.

Urban bird observers will not be surprised to learn that the report found the strongest increases in urban native bird populations to be: wild turkey, double-crested cormorant, vultures, gulls, doves, house finch, and great-tailed grackle.

The report summary emphasizes the important role that we human occupants of the city can play in helping these birds.

“The wide variety of native birds that thrive in urban areas underscores the importance of these artificial habitats to the survival of many bird populations. Creating greenspace in urban environments, landscaping with native plants in backyards and parks, adopting architecture and lighting systems that reduce collisions, and keeping pets indoors will provide the greatest benefit to breeding birds and migrants seeking safe places to rest and find food during their spectacular journeys.”

The Problem with Exotics, the Benefits of Hunting
Exotic -- that is, nonnative -- birds tend to have a significant negative effect on populations of native birds because they compete for food and shelter. Starlings, for example, will take over nest boxes from native birds, and house sparrows have been known to kill a nesting bird and build their own nests on top of their victims. The report tracks 17 exotic species of birds.

The good news is that the common exotics we have in the Twin Cities -- rock pigeons, starlings, and house sparrows -- have stabilized or even declined a little over the last 40 years. In other parts of the country, more recently introduced exotic species are growing rapidly.

And not all introduced species are problematic. Ring-necked pheasants are not native to Minnesota, or even the United States, but they do not pose a problem, likely because their numbers are controlled by hunting. In fact, the report indicates that hunters, and game bird advocacy groups like Pheasants Forever, have played a key role in helping preserve habitat and maintain stable populations of 19 species of native game birds tracked by the report.