Data on forest birdsong frequency before and after sunrise collected by IC recorders from 2009-2019

This data set is aimed at monitoring the effects of climate change on the timing of breeding by forest birds. The data were collected in the forests of Teshio (Hokkaido Pref.), Ashoro (Hokkaido Pref.), Tomakomai (Hokkaido Pref.), Kayanodaira (Nagano Pref.), Ooyamazawa (Saitama Pref.) and Ichinomata (Kochi Pref.) by using Integrated Circuit (IC) recorders between April to May, 2009-2019. We listened to the recorded sounds to identify bird species and sound type (S: song, D: drumming, C: call). We collected the data in two minute-intervals during two periods each morning. The first period was from six minutes before sunrise to four minutes after sunrise, and the second period was from 50 minutes to 60 minutes after sunrise.