It seems the the main ingredient "partridge" and the bits that go in it and on it to roast are missing from the ingredients list in the online recipe. (Bacon, garlic, sprigs of thyme and rosemary).

http://www.itv.com/lifestyle/food/britainsbestdish/recipes2009/roastsussexpartridge/default.html  

I guess you could look in the preparation method and start from there, but it might be easier to include them in the ingredients. Looks lovely.