I strongly recommend cooking it for a very long time at a lower temperature, and using a meat thermometer to check doneness.
I do this for every sort of bird, and it always works - you need a bit of a blast at a higher temperature to brown the skin, but if the whole thing is cooked at, say, 140C, or even lower, it comes out much more tender and moist.
(This year we're getting a pheasant stuffed inside a chicken, stuffed inside a goose - I'm putting it in the oven on the 24th, I think.)