What's the difference between gruuse and partridge?
I can't help but think of the first two answers you have given.There is more information on the topic here.You are the judge.;o)
The bird most often referred to as a "partridge" is actually a grouse.The "Ruffed Grouse" gets its name from the dark brown/black feathered "ruffs" on each side of its neck.
Some members of the grouse family may be mistaken for partridges, but I think you will find the mistake made most by hunters who owe their upbringing to heritage.
The USA has true partridge, two in particular, and they are found in two completely different types of terrain.Both of them are imported birds.The Hungarian Partridge is found in the prairie states where it prefers the open grain fields.You may need a good pair of hiking boots if you want to challenge the Chukar Partridge in the more mountainous terrain of the western states.