Sandwich Tern
Sterna sandvicensis

One of the first of the summer migrants to arrive in the spring, sandwich terns are often flying around Portland Harbour in mid-March.

They hang around through most of the summer even though they don't breed any closer than Brownsea Island.

Then by July they are back with their young, remaining until October.

Some years one or two remain in Portland Harbour through the winter, the only tern that ever does this.