The European starlings are robin-sized birds, maturing to a length of about 20-22 centimeters and weighing 70-100 grams. Both sexes have a very colorful plumage, with a speckled green and purplish-black iridescence covering their back, nape, and chest. In winter, the tips of their feathers turn white or cream against the dusky black plumage, creating the characteristic “flecking” effect. During this time, males also develop elongated breeding plumage on his breast, while his back, sides, and rump turn into iridescent green. The female lacks the breeding plumage but retains more of the white-colored flecks.
Both the male and the female undergo a complete molt once a year. During the breeding season (January-June), the males display a steel-blue spot at the base of their beaks, while females have a pale pink speck. Their pointed bill is yellow during the mating season and gradually changes to a dark brown in winter. Legs of both sexes are pinkish red. Juveniles are drab-colored; they display a brownish-black bill all year-long and a gray-brown shade overall,lacking the fine glossy plumage of adults. Their wings have more rounded tips.
Basically inexistent in North America prior to the 1890s, the current population of European starlings exceeds 200 million birds, and their range expands from Alaska to northern Mexico. Starlings, along with other introduced species, are not protected under the Migratory Birds Convention Act (MGCA) and are considered pests in most agricultural areas.
European starlings are found primarily in non-mountainous areas. They are cavity nesters, and during the mating season, they often compete with native North American birds, including eastern bluebirds and black-capped chickadees, for suitable nesting sites. Because they are larger and more aggressive than their competitors, starlings not only defeat but also kill them in the process.
Mating season usually begins in early spring and ends in summer, but its length may differ from year to year. All starlings in an area commonly lay eggs at the same time; the clutch contains 4-7 glossy light blue eggs, which are incubated by both parents for a period of approximately 12 to 15 days. In the beginning, the nestlings depend on their parents for food, but they will soon gain autonomy and leave the nest before the month is over. It is possible for starlings to produce more than one clutch in a year; in that case, males will provide almost no care (feeding and removing the fecal sacs) to the last clutches.
Starlings are highly vocal birds, and except during the molting season when they remain silent for the most part, they use their impressive vocal abilities and mimicry skills to communicate with one another. They have about ten different types of calls to inform others about their location, potential dangers, and their mood. Their repertoire contains two classes of songs – whistled or warbled – that vary in length in scope. They can also imitate the sounds of other birds and animals, including frogs, goats, and cats, and also those of humans.
In terms of diet, European starlings aren’t too picky. They eat a variety of foods (both plant and animal) all year round. Adults’ diet consists primarily of nuts, seeds, fruit, and plants, but they will also eat soft invertebrates (fed especially to the nestlings), centipedes, spiders, butterflies, and worms. Starlings in agricultural regions get their meals from crop soil, sewage treatment beds, farmyards, and livestock feeding areas.
European starlings are a nuisance in urban/suburban areas and have a significant negative impact on their environment:
Habitat modification.As with any other pests, European starlings can be removed from an area by eliminating potential water sources, foraging areas, and nesting locations. This method is somewhat successful for relatively small residential areas. Near farms and agricultural areas or around airports where the birds pose serious health and economic risks, habitat modification has little success over the long term.
Exclusion.Exclusion is by far the most preferred and successful control method to most nuisance bird problems that occur inside buildings. All openings larger than 1 inch should be sealed with hardware cloth and other suitable materials (after ensuring there are no birds trapped inside the structure). Place a wooden or metal covering or porcupine wires on ledges to prevent starlings from roosting. Nylon and plastic netting may be used to cover the underside of roof beams or to protect fruit crops such as grapes, cherries, and berry bushes. Wide plastic or rubber strips can be hung with 2 inch-gaps between them to prevent starlings from gaining access inside farm buildings while allowing people and livestock to enter.
Trapping.This method can provide somewhat successful results in areas where starling populations are causing damage to farms, livestock facilities, and airports, or where other techniques have failed. Nest-box traps, used during the nesting season, and decoy traps, most effective when the starlings are flocking, are the two most common types of traps.For example, a well-placed and properly maintained decoy trap can catch up to 100 starlings per day.
Frightening.Frightening devices such as recorded distress and alarm calls, lights, bright objects, chemical frightening agents, pyrotechnics, and various other stimuli can be used to disperse starlings from roosts, small-scale fruit crops, and other areas where they might cause damage.
Using a combination of habitat modification techniques and bird scaring methods at the same time will provide the best results for long-term population control. Because starlings are highly adaptive, reliance upon a single technique will quickly become ineffective; the best approach is to make the environment unattractive for them and actively remove invaders. Such integrative approach is best conducted by a professional wildlife control company that makes use of humane and non-toxic treatments for European starling control, management, and prevention.