The U.S. Postal Service is issuing a raft of new stamps today to celebrate the 50th anniversary of the National Marine Sanctuary System, including two Hawaii sites. A stamp for Papaha­naumokuakea Marine National Monument features two red-footed boobies, and the Hawaiian Islands Humpback Whale National Marine Sanctuary stamp depicts a Hawaiian monk seal.

“We are pleased and honored to be able to highlight the two Hawaii marine sanctuaries on these stamps, to do our small part in highlighting the decades-long efforts of conservationists nationwide,” said USPS spokesperson Duke Gonzales.

President George W. Bush established the Northwestern Hawaiian Islands National Monument in 2006. In 2016, President Barack Obama expanded it to more than 582,000 square miles of water, creating the planet’s largest conservation area.

The Hawaiian Islands Humpback Whale National Marine Sanctuary encompasses sensitive humpback breeding grounds in waters shallower than about 600 feet between Molokai, Lanai and Maui, and along sections of Kauai, Hawaii island and Oahu, according to the National Oceanographic and Atmospheric Administration. Congress designated it a sanctuary in 1992.

Other sanctuaries featured on the stamps include those in American Samoa, the Channel Islands and the Florida Keys. The stamps will be available for purchase today at larger post offices across Hawaii.