( CNN ) -- Beach-bound travelers are keeping a close eye on the spread of oil along the Gulf Coast and weighing vacation decisions . Oil has come ashore in Louisiana , Mississippi , Alabama and Florida , and cleanup is under way in some areas . Here are some of the latest updates from coastal destinations affected by the oil spill : . Gulf Islands National Seashore . All of the Gulf Islands National Seashore sites are open , according to the National Park Service website . The park service reports that crews found `` very light occurrences of oil '' on Horn and Petit Bois islands in Mississippi . Petit Bois island was cleaned up and has been free of oil as of Sunday , the site said . The spill also has affected parts of the Gulf Islands National Seashore in Florida . Cleanup crews have been working on medium and heavier oil coverage at Perdido Key , Fort Pickens and Santa Rosa . Gulf Shores and Orange Beach , Alabama . In Alabama , the Department of Public Health has issued an advisory against swimming in Gulf waters or in bay waters close to Fort Morgan . The beaches remain open . The pier at Gulf State Park in Gulf Shores is closed to fishing but open for sightseeing , according to the Alabama Gulf Coast Convention and Visitors Bureau . Oil has been reported on shore at Dauphin Island , Fort Morgan and Gulf Shores . Pensacola and Perdido Key , Florida . The waters in Pensacola and Perdido Key are open Monday for swimming and fishing , according to the Pensacola Bay Area Convention and Visitors Bureau . Officials have not issued closures or health advisories for the area , the bureau 's website said . Several tar balls were spotted in the area over the weekend . `` According to [ the National Oceanic and Atmospheric Administration ] , tarballs do not pose a health risk to the average person , but visitors are advised not to pick them up , '' the website said .
Gulf Islands National Park sites open ; some are detected on site . State officials have issued an advisory against swimming in the Gulf waters . Miami and Perdido Key , Florida , waters open Monday for swimming and fishing .