Minnesota's nonnative birds range from rare to pesky

Birds are not just birds. They're also the stuff of official state lists.

While most of our birds in Minnesota are native species that belong here, the state also tracks unregulated nonnative species, unlisted nonnative species and regulated invasive species.

The Minnesota Department of Natural Resources (DNR) has lists, rules and regulations for this. The manager of these lists is Laura Van Riper, terrestrial invasive species coordinator in the Division of Ecological and Water Resources.

This line of inquiry began when I asked Van Riper about house sparrows. She answered with details for the species on her lists.

The sparrows are unregulated nonnative species. That means these birds are not subject to regulation under invasive species statutes.

Unregulated birds are either widespread, like the sparrows, or unlikely to survive outside of captivity, or nonnative game species.

The latter are ring-necked pheasants, the gray partridge, also known as Hungarian partridge, and chukar, another partridge found much more easily in the western part of the U.S. (Our chukars are in all likelihood escapees.) While invasive species statutes don't apply to these birds, hunting regulations do.

Regulated invasive species are controlled because they cause problems when mixed with native birds. On the Minnesota list are the Egyptian goose, Sichuan pheasant and mute swan.

The most often seen of the three are mute swans, here as captives usually kept by waterfowl fanciers. The birds rarely escape, but they do. If and when, they are removed by the DNR.

Birders who keep life lists might race to see the swan before it disappears because the American Birding Association accepts mute swans as wild.

Both Wisconsin and Michigan have mute swan problems. People who appreciate the bird's beauty but not its impact on habitat and native birds often vigorously oppose control.

The swans can overwhelm submerged plants that are food for native species. Their aggressive eating habits can muddy water, reducing its quality. They also are aggressive toward other bird species and sometimes people.

Starlings in Minnesota are also listed as an invasive species. They are the only species in that category to have their own DNR webpage.

Van Riper said that is because people ask a lot of questions about starlings.

Perhaps that's because our starling is included on the list of the world's worst 100 invasive species. The list is kept by the International Union for Conservation of Nature.

Starlings are numerous, intelligent and quick to leave if any threat is seen. They nest in cavities. Our control of landscape has meant loss of cavities, increasing competition for housing with native birds like bluebirds and purple martins. Starlings love martin houses.

Our starling species, Latin name Sturnus vulgaris (literally starling common) belongs to a large family of many species found worldwide. Not all members have the reputation of ours.

So, why didn't we get the nightingale?

Read Jim Williams' birding blog at startribune.com/wingnut.