Experts Offer Solutions for Starlings Gathering at Stations

Even with the windows closed, “it’s so loud that I’m vacuuming by ……”

In the evening, flocks of starlings fly in so fast that the sky turns black. In the vicinity of Kasukabe Station in Saitama Prefecture, they sing all night long, and even when the windows are closed, their voices are so loud that they are vacuuming nearby, causing sleep deprivation, residents in the neighborhood complain.

It is not only in front of Kasukabe Station. In Chiba Prefecture, including in front of Tsudanuma and Kashiwanoha Campus stations, large flocks of starlings flock to the area in the evening in search of a roost.

But why in front of train stations?

The starlings’ natural enemies are goshawks and falcons. There are few of these birds in urban areas, and falcons will aim at them in a swoop, but if there is a building, they will not attack because of the risk of colliding with them.

Buildings can block the wind, so the temperature does not drop so much in winter, and even when typhoons come, the wind can be blocked. There are so many buildings in front of the station that I think they use the trees in front of the station as roosting sites.”

says Shigeharu Koshikawa, vice president of the Urban Bird Study Group. In fact, Koshikawa’s research has shown that roosts disappear when buildings are demolished.

Another reason is that there are many zelkova trees in front of the station. Starlings often choose zelkova trees for roosting.

The zelkova trees are finely branched and their branches tend to sway. When a foreign enemy comes, the vibration is easily transmitted, so they seem to choose it as a roosting site.

It was in the 1980s that starlings began using the zelkova trees in front of the station as roosting sites.

Until then, they roosted in windbreaks and riverside forests in the suburbs, but development has progressed and windbreaks and riverside forests have disappeared. We think this is why they moved to the front of the station, where there are many zelkova trees.”

Even if you remove them, they just move to another place. ……

In large flocks, 30,000 or 40,000 birds can gather. Not only do they chirp, but their feces and feathers fall in, making it impossible to hang laundry outside. When feathers are flown in, restaurants can become a matter of life and death. The government has received such complaints, and various measures have been taken. One such measure is to prune the branches of the zelkova trees that are used as roosts.

In some severe cases, the branches were not pruned at all, but rather were whacked and the zelkova trees were shaved to the ground,” said Mr. Kato.

This was not the end of the problem. The starlings, driven from their roosts, simply move on. There was even a case where starlings evicted from in front of Tsudanuma Station moved to the neighboring Kita-Narashino Station.

When they disappear from your area, you might think you’ve succeeded in getting rid of them, but you’ll only cause trouble for other municipalities.”

In addition to pruning, a variety of other eviction tactics have been used, including setting off rocket fireworks, setting off firecrackers, distress calls that play recordings of starlings’ screeching voices, and ultrasonic waves, vibrations, and flashing lights,

“The evicted starlings simply move to another station or municipality. This is not a solution.

If they move to another location, that’s still fine, but eventually they may start roosting on power lines, billboards, etc.

If that happens, they will leave the municipality’s jurisdiction. We have to ask the power company or building management company to take action.

Starlings are also anxious about places that are in full view, such as power lines. But if they learn that they can roost here, they will congregate there.

Starlings that roost in zelkova trees move to bamboo forests in the suburbs when the zelkova trees lose their leaves, but if they roost on power lines, they will be there all year round.

What should we do?

We don’t have to try to get rid of them all.

Prune only the trees in the shopping arcade and other areas where they are a nuisance to residents, and leave the trees in roundabouts and parks where they do not cause much damage to people untouched. This way, starlings will roost in areas where they are not a nuisance and will not move to other municipalities, thus reducing the spread of starling roosts.

When pruning, cut the trees in a rounded shape and cover them with bird netting. If the number of roosting trees decreases, Mr. Koshikawa says it is important to consult with neighboring municipalities before proceeding with measures.

Starlings begin nesting in late March and laying eggs in mid-April. The number of starlings at their roosts increases around October. It is necessary to take countermeasures such as pruning in the spring, rather than in the fall when their numbers increase.

Why don’t you care!　The zelkova trees along Omotesando Avenue are also a starling roost, but ……

But are starlings a problem only in Chiba and Saitama prefectures?

The largest number of starlings are in the Kanto region. There are also roosting problems in Kansai and Aichi prefectures. There are also many areas in Tokyo where roosts are a problem.

You may not be aware of it, but the zelkova trees along Omotesando Avenue are also roosting areas.

Perhaps because I didn’t pay attention, I didn’t notice the feces on the sidewalks.

The zelkova trees along the Omotesando Boulevard are so magnificent that their leaves may catch the feces and keep it from falling onto the sidewalk. The large size of the trees means that there is more space between individuals, so it is probably not as much of a problem as it is in front of the station.

Mr. Koshikawa says that the reason why the singing can be heard all night long is because the birds are constantly moving within the trees, and when one bird starts singing, it spreads to the whole area.

If this is the case, it may be better to grow a large zelkova tree than to prune it.

In the Chronicle, starlings are classified as part of the fall season, and people in the past would sense that fall had arrived when they saw a flock of starlings. Perhaps that kind of peace of mind is gone now.”

Koshikawa says that in order to coexist with starlings, we need to start thinking about urban development.

Starlings eat bedbugs, caterpillars, and other agricultural pests, and they also play the role of seed dispersers, eating nuts and dropping seeds with their droppings.

We must think of ways to coexist instead of putting humans first.

If we plant zelkova trees on a wide road with plenty of space, starlings will not be so much of a problem even if they gather. Besides, above all, wouldn’t a world without birds be scary ……”

Shigeharu Koshikawa Until 2016, he taught at a Chiba prefectural high school. Has been involved in research on urban birds such as starlings, crows, and swallows. He is the vice president of the Urban Bird Study Group. He has been studying and researching starlings for more than 40 years and has also been an instructor at the University of Nature Observation since 2017.