I would say it is a cross between two spaniel breeds, maybe Cocker/Field or Clumber, although the head has a look of an Irish Water Spaniel, which would explain the curls and the colour. It certainly doesn't look like an American Cocker Spaniel or pure Cocker, although some of the 'working' strains look very different from the show ones. Is it something you just found, or is it a dog you know?
Sorry didn't mean Clumber,meant Sussex! There is also a breed called an American Water Spaniel, just been recognised in this country, which has the coat/colour of this dog, although not the docked tail.
It's not a sussex spaniel as they are flat coated and liver coloured. American water spaniels look like the picture but the coat is usually brown so maybe this dog is a cross between that and a black spaniel?