Experts at the National University (UNA) found tissue damage, algae and sea water in the lungs of sea turtles to conclude that some 280 of them that were found dead in Costa Rica’s southern Pacific last week died by drowning.
Studies also ruled out the presence of bacteria, fungi, viruses or toxic substances as a cause of death.
Members of the Wider Caribbean Sea Turtle Network (WIDECAST) sent three dead turtles to the Veterinary School laboratory at UNA and the results released Friday afternoon confirmed the death was by asphyxiation.
Veterinarians found inflammation and damage to the respiratory system, so it is suspected that the turtles drowned after beign caught in nylon fishing lines which use lots of hooks and live bait.
Fishing hooks and lines were actually part of the evidence found by WIDECAST teams in the area where hundreds of olive ridley turtles, green turtles, marlin and sailfish washed ashore along 10 kilometers of coast between Punta Banco and Playa Pavones, in the Southern Zone.
Officials from the Costa Rican Fisheries Institute, the Environment Ministry, the Coast Guard and the National Animal Health Service formed a committee and filed a complaint against “unknown subjects” for the deaths, in order to proceed with an investigation.
In Costa Rica, it is prohibited to fish with live bait from the high tide line up to 30 miles offshore, to prevent turtles and other animals from being snared by the hooks.