I saw these in Drumpellier park in Glasgow, think they may be a goosander and a Cayuga duck, are they unusual for Scotland?

Looks like a female Goosander - and regarding the Cayuga Duck, I think you have a hybrid ('mixed' Mallards can also been known as Manky Mallards) because there is definitely some Cayuga in there but the legs and feet aren't black so that says there has been some hybrid activity.

And just to add - both not unusual for the location.

I reckon Rsp is right on both id's the curly tail on the duck are usually a good pointer to there being a bit of Mallard in the mix