Now we know where Juvenile sea turtles Hide

PBS is showing a nature film following a loggerhead turtle on a looooooong journey.

Nature . TV Schedule | PBS

Voyage of the Lonely Turtle
Sunday, April 15, 8:00pm
CHANNEL 4 (UNC-TV)

F. Murray Abraham narrates this account of a 30-year-old female loggerhead turtle’s journey from Mexico to Japan (its birthplace) to lay eggs. During the yearlong trip (travel speed: 1mph), she passes an array of marine creatures, including blue whales.

Here’s a press release on the show, sounds great, don’t forget to watch (or record!): April 15th at 8:00 PM.

Personal Note
I swear, this blog has gone to pot. Either I’ve been too busy at work (yes, that does not explain everything), or I have not been thinking enough. I started this blog so that when I saw something interesting, I would have to think a little bit, and gather some information to write about what I saw/read. Apparently, I don’t read/see any more (which is not true), I don’t think any more (possible), or I am too lazy to spend enough time thinking to throw a coherent blog post together.

This has got to stop, and it stops right now!!
End Personal Note
Back to the topic on hand…

The Pacific Leatherback is in serious trouble and is slated to go extinct soon.

ENN News Network

Experts at the Bellagio Sea Turtle Conservation Initiative have just concluded a conference to save the imperiled Pacific leatherback sea turtle from extinction. The International Union for the Conservation of Nature and Natural Resources (IUCN) has classified Pacific leatherbacks as critically endangered.

The meeting convened an internationally diverse group of scientists, conservationists, economists, fund-raisers and policy makers. One focus was the development of immediate actions to boost hatchling production of the Western Pacific nesting populations by protecting nests from predation, beach erosion and human consumption on the beaches of Indonesia, Papua New Guinea, Solomon Islands, Vanuatu, Vietnam and Malaysia. Although there are still hundreds of turtles nesting, with 75 percent in one area on the north coast of Papua (Indonesia), researchers are concerned by new information indicating that the majority of nests laid are not producing hatchlings. Some simple procedures have been developed to improve hatch success, and applying these techniques now may ensure the populations are sustained in the future.

Some radical measures have been suggested, including cloning. Well, highly unlikely. Jurassic Park horrors and ethical dilemmas aside, cloning reptiles ain’t so easy.

What ails the Pacific Leatherback? Their numbers have dropped from 115000 reproductive females to less than 3000. This news release from a 2004 conference has more. But the usual suspects are destruction of nesting habitats, long line fishing, egg poaching, and to a more uncertain degree, climate change.

It’s depressing, I’ve never seen a leatherback, I guess I need to get on the case and see one before they disappear for ever.

If you did not know already, sea turtles tend to nest on (or close to) the beaches they were born at. It is known that they use the Earth’s magnetic fields to navigate. Here’s an article on the navigational natations (I strain to alliterate at times, but natation means swimming!) of the Green Turtle.

ScienceDaily: How Do Marine Turtles Return To The Same Beach To Lay Their Eggs?

I flagged this article not because it tells us much new, but just adds some nuances to sea turtle navigation.

The study has shown that the marine turtles’ navigation system allows them to maintain their course towards the egg-laying site wherever they find themselves. It is almost as if they were equipped with a compass pointing towards the beach in question. So they can correct any deflection they are subject to: transport by boat, ocean currents… But, unlike human navigators, they are not able to correct for ocean drift in plotting their course. So the movements recorded by the satellite are a combination of deliberate action by the turtles and the effect of currents. So it appears that the turtles’ navigation system is relatively simple and may cause them to be wander at sea for long periods during adverse ocean conditions. One turtle released 250 km from its egg-laying site on Europa traveled more than 3 500 km in two months before returning there!

Well, that’s interesting, if not surprising. It’s one thing to have a magnetic bookmark of a destination in your head (pretty wonderful thing, I wish I had it!) and swim continually towards this destination. It’s quite another thing to keep track of complex parameters like ocean drift and keep correcting continuously.

In essence, what they’re saying is that turtles home in on their destinations, but don’t always take the shortest way in because they tend to drift and not correct for this drift dynamically. It is not evolutionarily necessary because turtles probably do not get thrown way of course often enough that evolving even more sophisticated navigational systems (Garmin?) would provide a significant enough survival advantage.

In the Mozambique Channel, between the east coast of Africa and Madagascar, on the beaches of the French Islands of Europa and Mayotte, they caught turtles at the beginning of their egg-laying cycle, so that the animals were strongly impelled to return to this area to complete their cycle. After having Argos transmitters fitted to their shells in order to satellite track their return journey to the beach, the animals were released in open sea, several hundred kilometers from the egg-laying site.

Now that’s just mean! Imagine being kidnapped, tagged and released many miles away from home, and having to find your way back. Apparently, these turtles did it. Man, that would be such a cool navigational aid to have, quite a party trick!

This article brings up some interesting information about sea turtle poaching in Mexico, including the fact that sea turtle eggs are considered aphrodisiacal in certain cultures…

Real Men Don’t Eat Turtle Eggs : To Fight Turtle Poaching, Campaigners Hit Below the Belt (By C.J. Bahnsen)

But there have been recent gains. WiLDCOAST, a small conservation organization also co-founded by Nichols, has implemented a media campaign. It started in 2005, when Argentine singer and Playboy model Dorismar attracted controversial attention by appearing in television and poster PSAs, hitting Mexican men—who eat turtle eggs mistakenly believing they are aphrodisiacs—below the belt. The message above a salacious Dorismar reads: “My man doesn’t need to eat turtle eggs; because he knows they don’t make him more potent.” The bold campaign reached a global audience of 300 million and resulted in a decrease in consumption of sea turtle eggs.

Well, the unfortunate thing about aphrodisiacs is that if you believe, it works! So, I guess a Playboy model telling you that sea turtles eggs are baloney may work. They author does say there was a decrease in consumption, but presumably, it is not quite that easy to ascribe causation relationships to particular parts of a campaign!

Other highlights…

Turtle smuggling is thought to be a proving ground, a gateway into drug trafficking. Mexico is the principal transit country for 70 to 90 percent of cocaine entering the U.S., and the largest outside source of
marijuana and methamphetamine.

This, I did not know.

Grupo Tortuguero continues its David-vs.-Goliath efforts to co-opt fishermen and volunteers from Baja’s fishing communities to monitor, tag and protect sea turtles. The group has dozens of sites along the peninsula and all have drug issues, ranging from trafficking to addiction. “I’ve interacted with fishers who were not ‘poachers,’ but were poaching for money to feed their habit,” says Nichols

The article is interesting because it points out the similarities between sea turtle smuggling and drug smuggling, the use of young women, the co-opting of users to become dealers, the bribery of local officials, the organization to avoid capture, etc. Hmm…