This dataset contains first egg dates for great tits (Parus major) and blue tits (Cyanistes caeruleus) from Monks Wood, Brampton Wood and Wennington Wood in Cambridgeshire, England, over a 23 year period. The dataset runs from the breeding season in 1993 to the end of the breeding season in 2015. The first egg dates are presented as the number of days from the start date which was set as the 1st April each year. Because the timing of breeding of great tits and blue tits is influenced in large part by ambient temperature and the phenology of their main prey, the data were collected as a measure of spring phenology. These data comprise part of a larger long-term study of the influence of habitat (extent, structure and composition) and landscape factors on abundance, distribution and breeding success of woodland birds in English lowland deciduous woodland.
Publication date: 2016-04-07
Field data collected by trained and experienced personnel. Egg dates have been checked against original paper records. Numbers of lines of data have been checked and data values have been checked for outliers. Individual egg date values have been checked against mean values per year for each site.