Phenology is about the observation of natural events, recording when things happen, for example, when horse chestnut and ash trees come into leaf, or when the first swifts or bumblebees are seen. These timings vary from year to year. Through the recording of natural events over many years, one can look for trends and see if they are correlated with changes in the weather or other phenomena. Recent studies by researchers at Rothampstead, the Centre for Ecology and Hydrology, and the British Trust for Ornithology suggest that a number of different phenologies are changing.   They looked at various insect and bird populations in a variety of different habitats (urban gardens, agricultural systems, sand dunes, grassland, woodlands etc).  The broad conclusion was there was a “trend towards earlier phenologies for UK bird, moth and butterfly species across habitat types” . For example, aphids (which breed rapidly and can adapt to changing temperature quite quickly) now take flight some 30 days earlier in the year than fifty years ago.   Such phenological changes have ‘knock on’ effects.  For example, the earlier arrival of aphids can affect potato crops.  Aphids spread plant viruses and young potato plants are more susceptible to viral disease than older, more mature plants. Read more...