This flag although unofficial in the eyes of the establishment is the Flag of Anguilla. The three orange coloured dolphins  to represent endurance, unity and strength, and are in a circle for continuity. The flag has a white background, for peace and tranquility, with a turquoise-blue base representing the surrounding sea and also faith, youth and hope. Some facts from  http://www.gov.ai/flag.htm

The current British Flag for Anguilla has reduced the real flag to a mere emblem on  a flag where the Union-Jack colors dominate.

This flag on www.anguillanews.com is the first animated version available online.