Close-up of a shearwater’s bill. These birds have a characteristic tubular nasal passage that is used for olfaction. This ability to smell helps to locate patchily distributed prey at sea and may also help locate nesting colonies.

Close-up of a shearwater’s bill. These birds have a characteristic tubular nasal passage that is used for olfaction. This ability to smell helps to locate patchily distributed prey at sea and may also help locate nesting colonies.