Nature’s Calendar

Robert Marsham was born in Norfolk in 1708 and lived most of his life at Stratton Strawless. From 1736 he noted each year 27 ‘Indications of Spring’ including the dates of first flowering wood anemones, the leafing of beech, the first call of the cuckoo, the dates when rooks started their nest building, dates of oak and hawthorn coming into leaf and swallow arrival dates.

Following his death in 1797 successive generations of his family continued to record these signs of spring right up to 1958. At the time nobody realised how important these records would become. Today, with concern over climate change and its impact on wildlife and the natural world, these records have become of global importance as one of the longest and best sets of records linking climate and the natural world.

The Marsham records are the longest British records of phenology (the study of the timing of natural events) in Britain and one of the best in the world. His records can now be compared to temperature records and provide strong evidence of how global warming is leading to earlier springs. His records for hawthorn show how for each 1°C of temperature rise leafing can occur up to ten days earlier.