deer scarer; water-powered clacker
A traditional Japanese garden device: a bamboo tube that fills with water, tips, and clacks against a stone. Originally used to scare away birds and deer, now often decorative.
See also: 添水
I heard the sound of a deer scarer in the Japanese garden.
The deer scarer makes a clacking sound when the water fills up.
From 鹿 (shishi, 'deer') + 威し (odoshi, 'threatener, scarer'). The device was originally used to scare deer and birds away from gardens and fields.