Continued from Falconer Scares Away Crows From Mega Solar Plant (1)
Crows fly away upon arrival of falconer's car
The hawk was very effective. "It is a spectacle to see hundreds of crows fly away all at once seeing a single hawk, and I was surprised to know about the powerful influence of the hawk," Beppu said, talking about the impression he had looking at the way the falconer worked. In about one to two months after the start of flying the hawk, "the crows began to fly away when Yasui's passenger car carrying the hawk approached the site," he said.
Crows are very clever and never react to vehicles not driven by Yasui, even if they are the same model. They perhaps remember the driver or the license plate.
"Crows are chased away by hawks taking advantage of the cleverness of crows," Yasui said (Fig. 8).
Kites, for example, are also larger than crows and are superior to crows in claiming territory. However, kites eat dead animals only, excluding small ones such as frogs. On the other hand, hawks attack, kill and eat live rabbits, crows and other large animals, although kites and hawks are about the same size.
Crows know the nature of kites and are not scared too much by them. They sometimes invade the territory of kites and steal their food. However, they feel very threatened by hawks.
"Even if there are a large number of crows, they will all fly away when they see a single hawk," Yasui said. "They remember the places clearly and stay away from the places for a certain period."
Nearly all the crows that flew to the mega solar site were driven away by using the hawk during the first three months, and crows gradually stopped flying to the site in large numbers (Fig. 9). As a result, damage to the panels by crows, which was the concern, was nearly zero.
As such, the frequency of flying the hawk was reduced to once per week.
"Some of the crows chased away from the mega solar power plant may come back to the site to check the situation," Yasui said. "If they see the hawk again when they come back, they finally give up the site and move to other places. There is also a possibility that new crows fly to the mega solar power plant. In preparation for such situations, the hawk needs to be flown periodically after the three months to ensure that the crows move to other locations."