I have been a few times to Enoshima, a wonderful place which makes a perfect one day trip from Tokyo. The first time I went there I was surprised, and at the same time a little bit scared, by the amount of kites that were flying very close to our heads.
It seems like these birds of prey are very common in Enoshima and they cause some problems. This is one of the signs that warns about them.
The sign explains that kites have a sharp eyesight, they can see the food that you are holding in your hand and they can attack you from behind. The sign advises you to wear a cap or a hat and to use an umbrella if you are lying down at the beach.