Magnificent and messy, millions of starlings make annual winter appearance

Each year in Italy the harbinger of winter is announced with the beautiful sight of stormi di storni as large flocks of starlings swirl above the cities of Italy. I remember watching in awe as these flocks of swarmed over the city of Rome with acrobatic feats of swirls and swoops that rival any aerial display I have ever seen.

Officials estimate that 1 million to 5 million starlings have chosen the Eternal City as their wintering ground as they do as well in other cities. Every year the birds show up between October and February, migrating from the colder climate of Northern Europe to warmer climates in the south. The starlings have been coming to Italy for centuries. In ancient Rome, the augers, or priests and officials, were called upon to interpret the will of the gods by studying their formations.

During the day, the shiny dark-feathered starlings feed in rural areas before heading back to roost in the city whose lights protect them from predators and where temperatures are generally warmer. Ornithologists theorize that the birds flock together to protect themselves from their main predators of hawks and falcons but also for warmth and company as they prepare to roost.

These tiny birds, which measure up to 8 inches in length, are highly organized and as they take to the skies they come together in an enormous cloud of whirling wings as they spread out. Their movements are as coordinated as a military flyover, and they anticipate each other’s moves as they fly in different directions and then suddenly come back together as though the wind is separating them and then bringing them back into one entity. Their reaction time is said to be 13 times faster than a human as seen when one bird changes direction and just a second later the closet birds to that one will follow their path.

Their intricate and sudden swirls and swoops seem synchronized and uniform as each starling will align with seven others and coordinate their flight formation. These stunning aeronautics can last up to an hour and are a delight for tourists but not so much for residents.

As one can imagine, with such large numbers flying over city streets and monuments, they are dropping a great mess below them. Estimates are that each one produces 40 grams of guano daily, which is not quite up there with the daily ton of waste produced by the pigeons of St. Mark’s in Venice but is just as problematic.

This is not only unpleasant to people walking below them (you will often see residents walking with umbrellas during the swarming), but their waste corrodes monuments, makes roads and walkways slippery and requires continuous cleaning to mitigate damage and prevent accidents.

There have been various attempts to disperse the flocks with teams of environmental department workers spreading out across cities with bullhorns, recorded sounds of distressed starlings, flashlights, and other measures in an effort to split the flocks into smaller groups. Despite all these issues the arrival and aerial display these tiny birds bring over the skies of Italy remain one of the world’s greatest natural phenomena.

Sometime around March, after approximately five months in Italy, the majority of the starlings will take to the sky once more and head back to their breeding grounds in Scandinavia, leaving only a small population of birds behind.