Sea-Buckthorn (Hippophae rhamnoides)

Sea-buckthorn isn't actually a Buckthorn, but it is a native species, originally found on the east coast. It is extremely hardy and salt tolerant. 

Sea-buckthorn's bright orange berries are an important Winter food for Fieldfares and Thrushes in particular. In the Neolithic they were also a (rather unpleasant) staple for humans, although I have seen recipes for jelly and even a "topping for cheesecake" (!). I used to have a very nice French perfume with Sea-buckthorn as a key ingredient, though this seems to remain something of a speciality in a sub-region in Provenance. Sea-Buckthorn is also a food plant for Emperor and Ash Pug moth larvae, among others.

Please be careful where you plant Sea-Buckthorn; outside its natural range it can be invasive, particularly when planted in sand dunes. See below for more details.