Opening Summary
The European starling (Sturnus vulgaris) is a small to medium-sized songbird that is now found throughout much of North America. While native to Europe, Asia, and North Africa, the starling was intentionally introduced to North America in the late 19th century. This introduction is widely considered to be one of the most disastrous bird introductions in history.
The European starling was brought to North America primarily by Eugene Schieffelin. Schieffelin was a wealthy drug manufacturer who belonged to the American Acclimatization Society. This organization aimed to introduce all birds mentioned in the works of Shakespeare to North America. In 1890 and 1891, Schieffelin released approximately 100 starlings in New York City’s Central Park. From this relatively small initial introduction, the starling population exploded across the continent.
The success of the starling in North America can be attributed to its aggressive behavior and ability to adapt to human-altered environments. Today, the European starling is considered an invasive pest species across North America. The starling competes with many native cavity-nesting birds and causes extensive agricultural damage. While Schieffelin’s intentions were likely good-natured, the results of the starling introduction have been highly detrimental from an economic and ecological perspective.
Eugene Schieffelin and the American Acclimatization Society
Eugene Schieffelin was a wealthy New York drug manufacturer who belonged to the American Acclimatization Society in the late 1800s. This organization aimed to introduce species from Europe and Asia to North America for economic, recreational or cultural reasons.
One goal of the American Acclimatization Society was to introduce all birds mentioned in the works of Shakespeare to North America. Schieffelin was the head of the society’s committee focused on introducing Shakespeare’s birds. He believed that introducing these birds would make the American landscape feel more familiar to European settlers.
Between 1890 and 1891, Schieffelin made multiple releases of European starlings in New York City’s Central Park. He obtained the starlings from dealers in Liverpool, England and transported them by ship to New York. In total, he released approximately 100 birds.
The starling was not originally native to New York City or anywhere else in North America. However, Schieffelin saw the starling mentioned in Shakespeare’s works and believed they should inhabit North America as they did Europe. This intentional introduction by Schieffelin in the late 19th century was directly responsible for establishing starlings in North America.
Other Introductions by the American Acclimatization Society
The American Acclimatization Society was responsible for many other problematic introductions in addition to the starling:
- House sparrow – Native to Europe and Asia, house sparrows were introduced to North America in the 1850s. They are now abundant and cause agricultural damage and competition with native birds.
- European rabbit – Introduced for hunting and food. Rabbits cause extensive agricultural damage in parts of the western United States.
- Gypsy moth – Imported accidentally in 1868 for silk production experiments. Gypsy moths are now a serious forest pest.
- Common pheasant – Native to Asia, pheasants were introduced as a game bird between 1733 and the early 1900s. Pheasant populations are self-sustaining in parts of North America.
Like the starling, these species have all established successfully at the expense of native North American plants and animals. The ecology of North America was severely altered by the many introductions made by the American Acclimatization Society.
Success of Starlings in North America
Following Schieffelin’s initial introductions, starlings spread rapidly across North America. Just two decades after the initial release, starlings had reached as far west as Salt Lake City. By 1942, they occupied most of North America. Today, their range extends over almost all of Canada, the continental United States, and Alaska. Starling populations in North America today number over 200 million birds.
Several key factors contributed to the starling’s incredible success in colonizing North America:
- Aggressive behavior – Starlings will aggressively compete with other cavity-nesting birds for nest sites. They prevent native species like bluebirds and woodpeckers from using cavities.
- Diet – Starlings are able to consume a wide variety of foods including insects, seeds, fruits and human garbage. This diverse diet allows them to thrive across different habitats.
- Breeding ability – Starlings can raise two to three broods per year averaging 5 eggs per clutch. This high reproductive potential allows populations to grow quickly.
- Adaptability – Starlings readily occupy human-altered habitats like farmland, orchards, suburbs and city centers. This has allowed them to thrive around human settlement.
These traits have enabled the starling to successfully colonize a wide variety of North American environments. Today, starlings occur in virtually any open or semi-open habitat across North America.
Population Growth of Starlings across North America
| Year | Estimated Population |
|---|---|
| 1891 (introduction) | ~100 birds |
| 1900 | Several thousand birds |
| 1915 | 12.5 million birds |
| 1942 | Approximately 150 million birds |
| 2005 | Over 200 million birds |
This table illustrates just how rapidly starling populations grew across North America following Schieffelin’s introductions. Their populations continue to thrive over a century later.
Impacts of the Starling Introduction
The introduction of the European starling is widely regarded as one of the most damaging bird introductions in history. Starlings have had substantial ecological and economic impacts across North America:
Ecological Impacts
- Competition with native cavity-nesting birds – Starlings compete aggressively for nest cavities, reducing nesting locations for native birds. Populations of birds like bluebirds, woodpeckers, and Purple Martins have declined locally due to this competition.
- Consumption of native fruits – Large flocks will eat fruits on trees and bushes required by native wildlife.
- Displacement of native species – Abundant starlings displace native birds from favored feeding and nesting sites.
- Spread of disease – Starlings can spread transmissible diseases to native birds and wildlife.
- Predation on native species – Starlings will sometimes eat eggs and nestlings of other bird species.
By displacing native birds, consuming fruits, spreading disease, and disturbing natural ecosystems, starlings have had many negative ecological impacts across North America. Their presence has changed natural communities.
Economic Impacts
- Crop damage – Large foraging flocks will damage crops by eating newly planted seeds, sprouting crops, and ripening fruits.
- Livestock feed consumption – Starlings will eat large quantities of livestock feed and contaminate what they don’t consume with their droppings.
- Spread of disease to livestock – Starlings can transmit transmissible diseases to cattle and pigs.
- Damage to structures – Their droppings are corrosive and will damage wooden and metal structures.
- Aircraft strikes – Starlings are sometimes struck by planes during takeoff or landing, posing a safety risk.
- Declines in native species – Loss of vulnerable native species that control insect pests or pollinate crops.
Through consuming crops and livestock feed, damaging structures, and spreading disease, starlings impose substantial economic costs. Their presence is detrimental to agriculture and creates unnecessary safety risks.
Attempts to Control Starlings
Given the extensive damages caused by introduced starlings, there have been many attempts to control their populations:
- Nest destruction – Destroying starling nests and eggs in problem areas like on farms or in urban centers. This is labor-intensive and often ineffective since starlings can re-nest multiple times per year.
- Poison – Using toxic chemicals like DRC-1339 to poison and kill starlings. Poison also often kills non-target native birds.
- Trapping – Live trapping and euthanizing starlings. Difficult to trap enough birds to significantly reduce populations.
- Disruption – Using loud noises, distress calls or falconry birds to scare off starling flocks from areas like vineyards or airports. Provides temporary relief in some cases.
- Birth control – Applying birth control chemicals to feed. This has been tested but is not a viable long-term population control method.
Unfortunately, none of these methods have proven effective at controlling starling populations over large regions. The starling’s high reproduction rate makes it difficult to slow population growth. Complete eradication is not considered feasible at this point. Current management strategies focus on localized control to provide temporary relief from starling damage.
Conclusion
The introduction of the European starling to North America is a classic example of the unforeseen consequences of species introductions. Eugene Schieffelin intentionally released starlings in New York City in the 1890s in pursuit of a whimsical goal. From this relatively small introduction, starlings expanded to occupy the entire continent within a few decades.
While Schieffelin could not have predicted the aftermath, the starling introduction has caused extensive ecological and economic damage. Starlings aggressively compete with native cavity-nesting birds, consume crops and livestock feed, and spread disease. Despite control efforts, starling populations remain abundant across North America over a century after their introduction.
This highlights the risks of purposeful introductions of non-native species. Even species like starlings that seem innocuous can become invasive pests in new environments. The case of the starling introduction stands as a stark reminder of the unexpected impacts that introduced species can have.
