Status of Wrangel and Other Arctic Islands
http://2001-2009.state.gov/p/eur/rls/fs/20922.htm
No negotiations regarding the U.S.-Russia maritime boundary have occurred since 1990, when the U.S.-USSR Maritime Boundary Agreement was signed. The negotiations that led to that agreement did not address the status of Wrangel Island, Herald Island, Bennett Island, Jeannette Island, or Henrietta Island, all of which lie off Russia's Arctic coast, or Mednyy (Copper) Island or rocks off the coast of Mednyy Island in the Bering Sea. None of the islands or rocks above were included in the U.S. purchase of Alaska from Russia in 1867, and they have never been claimed by the United States, although Americans were involved in the discovery and exploration of some of them.
The U.S.-USSR Maritime Boundary Agreement, signed by the United States and the Soviet Union on June 1, 1990, defines our maritime boundary in the Arctic Ocean, Bering Sea, and northern Pacific Ocean. The U.S.-USSR Maritime Boundary Agreement is a treaty that requires ratification by both parties before it formally enters into force. The treaty was made public at the time of its signing. In a separate exchange of diplomatic notes, the two countries agreed to apply the agreement provisionally. The United States Senate gave its advice and consent to ratification of the U.S.-USSR Maritime Boundary Agreement on September 16, 1991.
The Russian Federation informed the United States Government by diplomatic note dated January 13, 1992, that it “continues to perform the rights and fulfill the obligations flowing from the international agreements” signed by the Soviet Union. The United States and the Russian Federation, which is considered to be the sole successor state to the treaty rights and obligations of the former Soviet Union for the purposes of the U.S.-USSR Maritime Boundary Agreement, are applying the treaty on a provisional basis, pending its ratification by the Russian Federation.
The United States regularly holds discussions with Russia on Bering Sea issues, but these discussions do not affect the placement of the U.S.-Russia boundary or the jurisdiction over any territory or the sovereignty of any territory. The U.S. has no intention of reopening discussion of the 1990 Maritime Boundary Treaty.
Note: I believe this is the source of the map used in the other websites.