Coastal communities around the world are losing millions of tourist dollars a year through the destruction of rare sea turtles, a report claims.
The loggerheads predate the dinosaurs (Image: Alan F Rees/ARCHELON)
The World Wide Fund for Nature (WWF) says living turtles are worth nearly three times as much as dead ones because of the tourism they attract.
Of the seven marine turtle species, three are critically endangered and a further three are endangered.
Campaigners hope the WWF findings will encourage better conservation methods.
Sea turtles are killed for their meat and shells, with money also earned through the sale of leather and eggs.
The leatherback turtle, which can grow up to 2.75m (9ft) long, has declined by 90% over the last 20 years.
The WWF report, Money Talks: Economic Aspects Of Marine Turtle Use And Conservation, draws an economic comparison between killing turtles or collecting their eggs with money generated through tourism.
After studying 18 sites in Africa, Asia, Latin America and the Caribbean, it says that marine turtle tourism is an investment in livelihoods and far more profitable both financially and for the future of ocean wildlife.
Half the sites which killed the species for money produced an average annual income from sea turtle products of $582,000 (£332,000).
The other half where turtles have been a tourist attraction had an income of $1.65m (£975,000).
Sea turtle tourism has become increasingly popular since the 1980s, and currently 175,000 people take turtle tours each year to more than 90 sites in 40 countries - the biggest is in Costa Rica.
Populations of sea turtles have been in decline because beaches where they usually nest have been transformed into tourist resorts, over-harvesting of turtles and eggs for food, and accidental deaths in fishing nets.
Tourists travel thousands of miles to see turtles like the olive ridley
Carlos Drews, WWF's coordinator for marine turtle conservation in Latin America and the Caribbean, has said the report's findings should encourage stronger conservation measures.
"This study confirms what we've suspected all along, sea turtles are worth more to local communities alive than dead.
"Developers, politicians and community leaders should start to see marine turtles as a valuable asset generating revenue and jobs."
The BBC's environment correspondent Tim Hirsch says that poor communities in the developing world will only be convinced of such a wildlife balance sheet if they get a fair share of the profits earned from ecotourism.