Japanese Tits tended to increase the caution levels in the breeding territoties of Japanese Sparrowhawks

Abstract

I recorded the caution behavior of Japanese Tits Parus minor.The tits sometimes give alarm calls against Oriental turtle doves Streptopelia orientalis probably because of the similarity of their flight form to that of a hawk. This behavior is thought to be a false recognition of tits that show their increased caution levels. I recorded the rate of this false recognition in the groves of Tokyo during late March to early May 2012 and 2013, and compared the difference of the rates between breeding (11 sites) and non breeding sites (17 sites) of Japanese Sparrowhawks Accipiter gularis.Japanese Tits frequency of alarm calls against Oriental turtle doves was significantly greater in the breeding sites of Japanese Sparrowhawks (61.0±12.5％，N=11) than in the non breeding sites (7.1±14.3％，N=17).It suggested that Japanese Tits tended to increase the caution levels in the breeding territories of predatory birds such as Japanese Sparrowhawks.