Xanthochroism in a Robin

When visiting Penhescyn tip near Menai Bridge today, in the bushes by the mini-roundabout,  I saw a pale yellowish/faun bird fly off a barrier into cover. After dumping my stuff and speaking to the gatekeeper I returned to the bush and after a while it revealed itself to be a Robin, with pale sandy/yellowishfeathers on the upper and underparts with the orangey breast and grey behind the eye being the only normal colour. It reminded me of the Rock pipit in Caernarfon a few years back (and more recently at Porthmadog), and Norman's "Desert-like" House Sparrow near Valley, also from about 5 years ago. When these birds fly, you initially think Yellow Canary! Xanthochroism is an abnormal plumage colouration with a surplus of yellow, also called flavism.