The threat of many species such as the olive ridley turtles and sharks is rising in Costa Rica due to Longline fishing. Shark populations are slowly dwindling becoming smaller over the last eleven years. Adult sharks were abundant especially juvenile sharks leading researchers to believe that these shark species have been overfished leaving the cost Rica longline fishery to blame. Researchers predict that there will be some significant effects. 80 percent of captures turtles are released but the long term affects are unknown. Researchers propose a solution to the problem to protect these species would be to enforce time and areas closures for longline fishing and placing observers on longline boats to improve fishing techniques to protect the endangered species of the sea turtles in Costa Rica. The most common targeted fish the mahi mahi was caught the most in cost Rica longline fishery. The olive ridley turtles also classified as vulnerable were the second most common species caught during the 1999-2010 period. Even a few deaths of reproducing females may take a significant toll when longlines are held in shallow water and close to the nesting beaches.