As World Water Week continues in Stockholm and CI expands our focus on freshwater security and species contributions, the results of a new analysis of the survival prospects for freshwater turtles were presented this week.
Mention the word ‘turtle,’ and the instant reaction from most people is, “Oh, I love them! It’s so amazing how they nest on the beach. They’re going extinct, right?” In the shadow of their charismatic sea turtle relatives, freshwater turtles rarely bask in the spotlight of public attention. Maybe it’s because, at least in the United States, freshwater turtles can still be seen without too much effort: Walk along a wetland, look down from a bridge or paddle your kayak, and chances are that you’ll see some small turtles swimming or basking in the sunshine.
The United States is a privileged place when it comes to turtles – it has more native and endemic species than any other country worldwide. And while habitat loss, traffic mortality and the collection of wild specimens for consumption and pets have reduced some populations and species, many others remain widespread and abundant.
Elsewhere, turtle species have not fared so well. The usual twin evils of direct exploitation and habitat loss have pushed over 40 percent of all 334 currently-known turtle species into a situation where they run a very real risk of extinction within our lifetimes. Nowhere are the threat percentages as high as in Asia.
As well as a pleasant sighting during a hike or paddle, freshwater turtles are useful to the ecosystem as a whole. In most cases, turtles’ ecological benefits are modest and in the background; they help balance the freshwater food web, they contribute to keeping water clean and healthy by scavenging dead animals, and they help keep populations of other species healthy by preying preferentially on slow, weak and sick animals. In some cases, though, turtles are of significant importance. Diamondback terrapins (Malaclemys terrapin) feed mainly on salt-marsh snails, which in the absence of terrapins will multiply to densities where the snails overgraze the marsh grasses, allowing erosion to eat away at the tidal shoreline.
Because of their life history dynamics, turtles are generally not a sustainable source of meat and food security for rural communities. However, many species have good potential for ecotourism or to produce hatchling turtles for the global pet trade. By collecting hatchling turtles in place of adults, people will allow the adult turtles to continue to reproduce in the wild, sustaining turtle populations. These types of sustainable initiatives can generate local income while recognizing the present and future value of wild turtles in the landscape.
There are enormous challenges on the conservation horizon. Some are greater priorities than others. And while the essential large-scale processes proceed, some of us will contribute by working on the smaller scale, trying to protect every species we can – to prevent any more turtle species from going extinct and to help keep common species common.
Peter Paul van Dijk is director of the Tortoise & Freshwater Turtle Conservation Program in CI’s President’s Office. Read more about some of the world’s most endangered freshwater and terrestrial turtles, check out our turtle photo gallery, and submit your turtle questions for Dr. van Dijk. He will answer a selection of these questions next week.