Increased By-Catch Rates in the Gulf of Taranto, Italy, in 20 Years: A Clue About Sea Turtle Population Trends?

Information on sea turtle population trends is fundamental to assess the population status and the effects of conservation measures, and is considered a priority for sea turtle conservation. To provide insights on trends at sea, we compared by-catch data from long-liners fishing in the Gulf of Taranto in 2 periods: 1978-1979 and 1998-2003. A total of 653 loggerhead sea turtles (Caretta caretta) were captured in 2679 fishing sets targeting swordfish and albacore tuna; catch rates were significantly higher in the second period, while average turtle size was smaller. Although possible effects of sampling techniques cannot be excluded, a negative trend in the number of turtles in the study area and period was unlikely.