TIMES-COLONIST (Victoria, British Columbia) 08 August 06 Hungry turtles can mistake plastic for food (Carrie West)
The big old leatherback turtle can boast many things. It's the largest living marine turtle in the world, reaching lengths of two metres. Its evolution dates back more than 100 million years. It also migrates further, dives deeper and grows a different shell than other sea turtles.
But it would gladly shed its bragging rights when it comes to being one of the most endangered species around. The future for this big old turtle is extremely tenuous, especially in the Pacific Ocean, where it is considered critically endangered.
The problem? Humans and tropical beaches. Although they spend their whole lives at sea, female leatherbacks crawl up onto sandy tropical beaches to lay eggs in the sand -- the same beaches that humans like to inhabit and develop. Besides poaching of eggs and loss of beach habitat, the infant turtles are bothered by artificial light coming from human structures. The littlest leatherbacks should hatch and instinctively crawl toward the lit ocean (brighter than land). But artificial light confuses them and they crawl the wrong way. Nesting at most Pacific beaches has dipped over 80 per cent.
The leatherbacks that hang out in B.C. waters between July and September appear to nest mostly around Indonesia and Papua New Guinea. They swim clear across the Pacific to feed off the west coast of North America. The attraction? Jellyfish. We've got them and they want them. "It seems like a very odd prey source, being that it's majority water and a little bit of gelatin," says Lisa Spaven, a federal leatherback-research technician.
Sunfish called "mola mola" also crave these jellyfish, so if you see any around, keep your eyes peeled for leatherbacks. Since 1931, there have been 113 reported leatherback sightings in B.C. waters. The recent hotspots seem to be the west coasts of Vancouver Island and the Charlottes. "There have been a few sightings in inland waters, like Denman Island, Victoria ... but they're more rare and a lot further back in history," says Spaven.
Researchers are still trying to figure out leatherback movements in B.C. waters and are eager for public help. If you see one call: 1-800-I-SAW-ONE. Leatherbacks have abnormally large front flippers and the shell isn't hard and bony like other marine turtles. Its carapace has seven longitudinal ridges and leathery skin, hence the name "leatherback."
Globally, the leatherback is on oodles of endangered-species lists. Besides its beach problems, it's nabbed by folks fishing for tuna. Leatherbacks can also get hit by ships and tangled in fishing gear. And they ingest plastic debris, like bags or even deflated balloons, probably mistaking it for floating jellyfish.
Leatherbacks have been spotted in all the world's oceans. But with problems at every turn, perhaps the world is getting too big for our big old turtle. In the Pacific, they could disappear in one or two human generations. Leathery old things are supposed to be tough. Let's hope this one is tough enough.
Hungry turtles can mistake plastic for food