from the UK Independent:
A red admiral, normally seen in Britain in summer, was photographed in February among snowdrops
…many of what used to be thought of as the traditional signs of spring are happening very much earlier, causing primroses, for example, spring flowers par excellence, to bloom in some parts of the country as early as November. Other traditional spring plants, such as dog’s mercury and the lesser celandine (a favourite of Wordsworth’s) can be seen in January rather than March.
And in what is perhaps an even more vivid change, dandelions and daisies, which used to come into flower in spring on lawns (where they were permitted), now flower in many places all winter long.
Insects are responding similarly. A number of butterflies that overwinter as hibernating adults can now be seen in January rather than March or April, including the peacock and the comma, and especially the red admiral.
This last species used to be a spring migrant from the Continent but, in the recent warmer winters, it has begun to overwinter here.
Bumblebees have similarly become visible in mid-winter, and frogspawn, usually laid about March, can be seen in December in the South-west and south Wales.
The changes and many others have been monitored in detail because in Britain there has been a renewal of the old discipline of phenology, or the study of the timings of natural events, which was favoured by the Victorians but largely abandoned by the 1950s.