A study by Exeter University into the global take of marine turtles has found that 42 countries have no legalisation in place to prevent fishing of endangered marine turtles and that the annual harvest is estimated to be around 42,000 turtles each year. The research looked at legal harvesting and how the impact compares with other threats to marine turtles.
All seven species of marine turtles are considered to be endangered by the IUCN Red List and the species are covered by CITES regulations to prevent international trade in turtles and turtle products. Each country though is responsible for controlling the harvesting of turtle within it’s own borders.
Frances Humber of Blue Ventures and a PhD student at the University of Exeter, who led the research, said: “This is the first study to comprehensively review the legal take of turtles in recent years, and allows us to assess the relative fisheries threats to this group of species. Despite increased national and international protection of marine turtles, direct legal take remains a major source of mortality. However, it is likely that a fraction of current marine turtle mortality take is legal, with greater threats from illegal fisheries and bycatch.”
Much of the legal harvest involves small coastal communities who rely on the turtle meat for food and who sell the meat and products in local markets for extra income. The fisheries are an important source of finance, protein and cultural identity.
Modern legal fisheries are in stark contrast to those that were operating in the 1960’s when turtle harvesting was at its peak. In the late 1960’s 17,000 tonnes of turtles a year were harvested and in 1960 in Mexico over 380,000 turtles were estimated to have been caught.
The researchers collated data for all seven species of marine turtles from over 500 publications and 150 in-country experts.
They estimate that currently more than 42,000 marine turtles are caught each year legally, of which over 80% are green turtles. Legal fisheries are concentrated in the wider Caribbean region, including several of the UKs Overseas Territories, and the Indo-Pacific region, with Papua New Guinea, Nicaragua and Australia together accounting for almost three quarters of the total.
The data indicates that since the 1980s more than 2 million turtles have been caught, although current levels are less than 60% of those in the 1980s.
The numbers surrounding the illegal harvesting of turtles is much more difficult to quantify as getting reliable data is not possible.
Dr Annette Broderick, of the Centre for Ecology and Conservation at the University of Exeter’s Penryn Campus in Cornwall, added: “We were surprised to find that there are 42 countries with no legislation in place that prohibits the harvest of marine turtles, although for many of these countries these harvests provide important sources of protein or income. It is however important to ensure that these fisheries are operating at a sustainable level.”
The article, ‘So Excellent a Fishe: A global overview of legal marine turtle fisheries’ is published in the latest edition of the journal Diversity and Distributions
Photo credit: University of Exeter: Peter Richardson