The peacock caterpillars in the nettles in Simpson’s Field are growing fast.
 Nettles are the preferred food plant of peacock caterpillars and this is where the female butterfly lays her small green eggs  in batches of anything up to 500, sometimes several layers deep.
 The newly hatched caterpillars spin a web around the top of their nettle and feed inside it until it is time to moult their skin  for the first time.
They leave this nest peppered with the skins they have shed and move on  in search of another nettle ; here they spin another nest web.
The developing caterpillars leave a trail of deserted webs  behind them and with each new instar  become more independent of the group and less dependent on the shelter of the web.
In their final instars, the caterpillars  leave their sibling group and feed by themselves. They look for sturdy stems as pupation sites; this pupa  is hanging head-down from a nettle stem.
The adult butterfly, large and colourful, hatches from the chrysalis after 12 – 14 days. Peacocks are nectar feeders and spread right through the park in search of flowers; you will see them in our hay fields on any sunny day.