USS Cobra (SP-626) was a United States Navy patrol vessel in commission from 1917 to 1919 that operated during World War I. She originally was constructed as a private motorboat. After the conclusion of her U.S. Navy career, she served as the fishery patrol vessel USFS Petrel for the United States Bureau of Fisheries from 1919 to 1934, operating in the waters of the Territory of Alaska.