Last week, I spent some time up on Northern Ireland's Rathlin Island. Whilst sitting in the harbour, I heard some strange noises coming from the rather dapper-looking bird in this picture. An eider duck.
It doesn't do justice to describe it, so why not listen to it on our eider page?
This image is one of thousands on RSPB images. Take a browse through, and if you something you like, you can even buy it as a canvas or print.
For more on our science, check out the RSPB Centre for Conservation Science web pages.