How fishermen can help
Trawl nets. Turtles are air-breathers and can drown if kept in the net for long. When they arrive on the boat, an important number of the turtles are very weak (even apparently dead). They may die if released in this condition, because they cannot swim to the surface to breath. Fishermen can let them recover on the boat before releasing them. This applies also to turtles caught by set nets.
Longlines. After capture, most turtles are released apparently in good condition, however the ingested hook and especially the line will kill many of them later on. Fishermen can cut the line close to the mouth, thus avoiding its ingestion. These best practices do not reduce the fishing efficiency and are usually adopted by informed fishermen.