The Odyssey crew rescued a sea turtle that was caught in discarded fishing gear in the eastern Pacific Ocean over two years ago. Watch the video report.
Photo: Chris Johnson
September 17, 2002
The Lives of Sea Turtles - Part 3 - "Threats"
This is Genevieve Johnson speaking to you from the Odyssey in the Seychelles.
Sea Turtles have survived on our planet for more than 150 million years. However, they now require only but a nudge to be propelled forever into oblivion. Due to the increase in human pressures around the world, extinction is a serious possibility for most sea turtle populations. There are comparatively few sea turtles surviving the 25 - 60 years it takes to reach their nesting age.
Dr. Jeanne Mortimer explains the threats sea turtles face on land and in the oceans:
Dr. Jeanne Mortimer
If you look back over human history, the biggest threats to turtles used to be that people killed them to eat their meat and to take their shells - Hawksbills especially which are the main species found here in the inner Seychelles. People made jewellery out of the scales on their shell and they also collected the eggs. These are all still problems over many parts of the world because turtles are a good source of food and when you have places where people are poor, you can't blame them for wanting to kill turtles to eat. Unfortunately, if they kill too many, they are not going to have that food source and the world is not going to have turtles.
Turtle populations all around the world have declined drastically really, because of this kind of over harvest. Unfortunately, we now have new problems including destruction of habitat. Most sea turtles nest on beautiful beaches that people also like. Throughout the world where ever turtles occur you also get human development of coastline. In places like the U.S. such as the Florida coastline, there are a lot of turtles nesting there while more and more people are developing that coastline. Usually when people develop the coastline it becomes unsuitable for turtles.
Another problem faced by turtles is pollution, when people dump things into the sea it can destroy their habitat.
Chemicals like oil, poison turtles, while they are also attracted to small floating objects like plastic. Turtles eat bits of plastic, many turtles wash ashore dead with their stomachs full of plastic. What happens is that the gut is full and the plastic doesn't pass through the turtle. It stays in the stomach and the turtle starves to death because their stomach is full but they are not getting any nutrition. Another big problem for turtles all over the world is accidental capture in fishing gear. This is not only a problem for turtles, it's a problem for birds, it's a problem for whales and it's a problem for all kinds of fish species that people don't even want to catch. Turtles are disappearing in many places because of this. The populations of Leatherback turtles which are wonderfully exciting turtles have declined by more than 95% in the Pacific Ocean. This is attributable to capture in driftnets, capture on squid lines and capture on longlines.
From the perspective of a turtle biologist, I say " isn't this terrible that the turtles are disappearing?" . But really there is a broader view and turtles are only one tiny component of an entire system. It's a symptom of what else is going on. It's the tip of the iceberg. These kinds of very destructive fishing techniques are just destroying the ecosystems of the ocean; it's horrifying when you realize what is going on. We need to look at turtles as an indicator of what is happening in the oceans and on land too - turtles are interesting because they cross over between land and sea.
The future of turtles depends on which populations of turtles we are talking about. I worked in Malaysia for several years and one species that we had there was the Leatherback turtles, which are now virtually extinct in Malaysia. There used to be 2,000 females nesting every year in the 1960's, when I was there in the late 80's there were down to 40 and I understand now that they are down to virtually nothing. Some populations are going extinct, some populations will go extinct, some have gone extinct, but I think in other areas where people do have an awareness and where governments are willing to take the necessary steps to protect their resources. It is optimistic.
The Odyssey crew often sees discarded fishing gear on beaches (like this one photographed in the Salmon Islands in the Chagos Archipelago) and floating in the open ocean.
Sea turtles around the globe often become entangled by discarded fishing gear and drown.
Photo: Chris Johnson
Here in Seychelles we still have a lot of problems but also some bright points. For example on Aldabra - Aldabra has been protected since1968 as a special reserve, and it has been a world heritage sight for nearly twenty years now. The Green turtle population on Aldabra has been increasing and it has been increasing significantly due to the protection it has received on Aldabra itself. But prior to the 1960's, turtles on Aldabra were being killed for there meat and the population had declined from an estimated 6,000 - 8,000 animals nesting each year to less than 1,000. However, over the last twenty years the numbers have actually been increasing. It really all depends on what people are willing to do.
What I would say to the general public is, obviously, don't eat turtle meat, don't eat turtle eggs and don't buy products made out of turtle. The shell trade is still a big problem for Hawksbill turtles. Although it is illegal now for any international trade to be going on in Hawksbill shell, there still is illegal trade going on. I would recommend if you are ever offered the opportunity to buy something made out of turtle shell, don't. Also I think we just need to be more aware about how we deal with our habitats. Support efforts that encourage non-destructive fishing techniques, for example dolphin-friendly tuna, turtle friendly shrimp, these are industries you should support. When there is evidence that something is destructive, make the sacrifice of not using it. Also be aware of developing or buying land along pristine coastlines that may be destroyed once the area becomes built up.
One reason why turtles make such an excellent indicator species and also an excellent 'flagship' species for conservation, meaning they can be used as a way to attract peoples attention, is that they nest on the shore so they are partly terrestrial so if you are going to protect turtles you have to protect beaches. You also have turtles living in mangrove areas, you have turtles living on seagrass pastures, you have turtles living on coral reefs, you have turtles living on mudflats, you have Leatherbacks feeding in really deep oceans and travelling throughout the oceans, going near the Arctic and the Antarctic and also in the tropical areas. You have young turtles living in the oceanic gyres at the surface of the sea, so almost everywhere there is sea, there are turtles. In order to protect turtles, we have to protect everything if we are going to protect all turtles.
As Jeanne emphasizes, there are several things that individuals can do to help make a difference to the lives of sea turtles. For instance, you should always dispose of rubbish responsibly, particularly plastic products such as shopping bags and old fishing gear. You should avoid buying turtle meat or other products made from marine turtles. If you ever see a turtle in the wild, observe it from a distance but never try to touch it or disturb its nesting site. Most important of all, you can try to learn more about the lives of sea turtles while educating and encouraging others to help protect these endangered animals and their environments.
Log by Genevieve & Chris Johnson with Dr. Jeanne Mortimer