Does anyone have any advice about the following?

My supervisor, who is relatively unknown, takes credit for my work (informally and formally) at every available opportunity. When introducing himself to someone, he'll say that he is researching on my topic area without reference to me, i.e. 'I am exploring the impacts of X on Y'. He'll make no mention of my contribution to the work unless forced to. This happens in informal meetings but also on funding bids where the biography mentions my work as his own and similarly at conferences.

I've no idea what to do! Obviously, I know it's a two-way street. He's my supervisor so he can claim to be contributing to my work and has every right to benefit from the publications etc., which are produced. What worries me is that unless I'm always watching what happens, he sells my work as his own, with no mention of my existence!

Has anyone else had a similar experience?