O’r dyddiad hwnnw, bydd yn ofyn cyfreithiol ar bawb sy’n cadw adar i gadw eu hadar dan do neu wedi’u gwahanu mewn ffordd arall oddi wrth adar gwyllt. Rhaid i bob ceidwad adolygu hefyd y mesurau bioddiogelwch ar y safle lle cedwir yr adar a gweithredu ar hynny.  Diben hyn yw cadw’r feirws rhag mynd i siediau’r adar, gan fod y feirws yn farwol i lawer o adar. Mae’r mesurau hyn yn ychwanegol at y rheini ym Mharth Atal Ffliw Adar Cymru, sy’n parhau’n hynod bwysig.
From this date, it will be a legal requirement for all keepers to keep their birds indoors or otherwise separated from wild birds.  All keepers must also complete and act upon a bespoke biosecurity review of the premises where birds are kept. This is to minimise the risk of virus entry in bird houses, which usually results in high mortality. These new measures are in addition to those in the Wales Avian Influenza Prevention Zone, which remain crucially important.