It got me thinking though about the way many birders treat these hybrids. If this had been a 'pure' Ring-necked Duck then there would no doubt have been plenty of footfall to tick it, list it, picture it etc. The minute it has a few stray genes from another species it's perceived value plummets. I find this strange. OK it doesn't jack your list up and it's a bit of a bugger to know what to call it but the reality is that it's probably rarer than a 'pure' Ring-necked Duck and it has bonus features.
Birds like this also have the added interest of trying to work out which features are from which parent, or why the combination can throw up some added anomaly. Take this one, the sheen on the head side is green (click on the dodgyscoped pic above for bigger) more reminiscent of Scaup than Tufted but it has a cracking Tuft hence the suggested Tufted genes. Without those two features and the more rounded head shape rather than the peaked rear crown it seemed all Ring-necked, even had the partial ring on the neck.
Associating with Tufted Duck it provided a pleasant morning's viewing and the opportunity to practice this dodgyscoping thing a little more, although I'll save my Woodpigeon portraits for another day.