But such combinations aren’t always the answer, especially when it comes to black eagles, says USDA biologist Brian Clover, who studies the interaction between humans and animals. In 2012, a Florida kindergarten hung three carcasses of eagles from trees, hoping to drive out an unwelcome swarm of hundreds of black eagles. But the birds stayed where they were. This was not surprising to the researchers, as they saw the group feeding on the remains of other eagles that had died on the property.
“Hanging things, no matter what they are, can suddenly become a fun game,” says biologist Volcan Brown of Hook Mountain Reserve in Pennsylvania, who has been searching for eagles all over the United States for more than a decade. According to him, vultures are so curious that it’s always about finding a balance between what scares birds and what they want to investigate.
Some conservationists swear by the “evil eye balloons”, which are helium-filled balloons with a huge eye on them that are supposed to evoke a giant predator. But other forest rangers laugh at it, sending pictures of eagles gnawing at such a balloon.
Motion Sprinklers have been found to be effective on roofs and scaffolds. But if there is a lot of water, it can form a small pond that eagles love to use to bathe and drink.
Lasers are also a popular USDA method. This method works, but there should always be someone directing the laser at the legs of each eagle. When eagles are a large group, it takes a lot of work.
Fireworks, in the form of flashes and explosions fired from specialized pistols, can also be effective, but they need to be fired often. This method is preferred at airports and is applied standardly, for example, in Hartsfield-Jackson in Atlanta, the busiest airport in the world.
Last December, a North Carolina high school installed a gas cannon on the roof to hunt dozens of vultures. Such devices produce light pops of about 130 decibels, which are just as loud as standing next to an ambulance siren. Kristy Woods, a mathematics professor at the school, said the Eagles left after using the rifle repeatedly, “but it didn’t seem to advance much.” “It looks like they have now decided to spend time on the local subway.”
Brown notes that vultures are habitual creatures, so it is important to intervene before certain behaviors become routine. Make sure nothing attracts him, like easily accessible litter or pet food, and make a lot of noise when they want to sleep.
Government researchers also plan to test Men of Heaven this month, those waving “ balloon men ” often used in sports matches.