Green Turtle Caught on a Longline Hook (IMAGE) Drexel University Caption Based on an 11-year observation study with scientific observers on longline fishing boats, researchers estimate that 23,000 green turtles and 699,000 olive ridley turtles were captured by longline fishing operations in the eastern Pacific off of Costa Rica between 1999 and 2010. They report that these fishing operations represent a significant threat to sea turtles as well as sharks. Credit Pretoma Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.