Glob. Change Biol. 10.1111/j.1365-2486.2010.02165.x (2010)

Credit: © ISTOCKPHOTO / DIRK FREDER

Recent changes in the seasonal timing of biological events such as flowering and migration have been linked to warmer temperatures. Now a study shows that such seasonal shifts are becoming increasingly common in the UK and could wreak havoc across ecosystems as they disturb the delicate balance of nature.

A team led by Stephen Thackeray of the Centre for Ecology and Hydrology in Lancaster, UK, looked at more than 25,500 records of the timing of biological events for 726 marine, terrestrial and freshwater species over a 30-year period from 1976 to 2005. During this period, all three of these environments experienced a warming trend of about 0.04–0.05 °C per year. Thackeray and colleagues found that over the 30 years under study, the timing of 84 per cent of spring and summer events moved forward. The shift was more rapid than suggested by previous studies, averaging almost 0.4 days per year.

Many organisms time their reproduction and migrations to coincide with maximum food availability. If warming is the cause of these seasonal shifts, the new study suggests that 'trophic mismatching', in which the arrival and reproduction of predators no longer synchronizes with access to food, could be more common in future.