Haiku such as "kyo" () may look like two syllables to English speakers but are in fact a single "on" (as well as a single syllable) in Japanese. In 1973, the Haiku Society of America noted that the norm for writers of haiku in English was to use 17 syllables, but they also noted a trend toward shorter haiku. Shorter haiku are very much more common in 21st century English haiku writing. Some translators of Japanese poetry have noted that about 12 syllables in English approximate the duration of 17 Japanese "on". Also in translations four lines is more appropriate for
Japanese bush warbler has led to the birds being kept as cage birds. Robert Young records that to encourage singing the cages of kept birds were covered with a wooden box with a small paper window that allowed only subdued light in. Along with the return of the barn swallow the bush warbler's call is viewed by Japanese as a herald of springtime. It is one of the favorite motifs of Japanese poetry, featured in many poems including those in "Man'yōshū" or "Kokin Wakashū". In haiku and renga, "uguisu" is one of the kigo which signify the early spring. In poetry the bird