Raine Island - Nature's Cradle on the Edge of the Coral Sea
Satellite Web Cast From Turtle Heaven and Hell
Journal Entry - 12 - 6 - 02 Tag Data Is In!
Another day is closing at the top of the Great Barrier Reef. The weather is changing slightly. No, its not snowing like it is back at home in Princeton, Newe Jersey. You would think I wouldn't miss that but when the sun is hot enough at 7:30 that it is hard to look at the beach, well a few inches of the white stuff would be fun for a few hours.

The wind has shifted to the North. What, you might ask, does this have to do with anything? Ah, well... that was my question. For the turtles the weather is all. As the weather has shifted in the last 24 hours the Raine Island Corporation expedition researchers have noticed a subtle shift (increase) in the number of turtles nesting on the West side of the island, in the lee of the island, which is why there were less turtles moving up the beach at 7 pm this evening on our beach which faces directly into the wind.
As a non- scientist I have to write these reptiles have it hard. They are driven to procreate and have to work their way through untold hardship to do just that. And when they get to their natal (birth) beach where they will nest some appear to become confused and really blow it. Generally speaking, green turtles leave the water to nest at or just after sunset and return to the water soon after they have attempted to nest, whether they were successful or not. This morning we watched one rather disoriented turtle leave the water at 11:00 am and move up the beach. Thankfully, she realised shortly after cresting the beach head that she was in the wrong place at the wrong time and turned back down, returning to the water in what might be called a hurry - for a turtle anyway.
The big news today is that after dinner the turtle tagging team and some volunteers went ashore in the dark to see if they could locate the two turtles to which they attached tags last night. They tagged two turtles: one which has successfully nested and laid a clutch of eggs and another which had failed and turned back to the sea. Then this Am the team took the rubber dinghy and motored off to see if they could locate the turtles with the receiver. They were actually able to hear one of the turtles for a short time before they lost the tag signal - the turtle was deep and well off shore.
Bit of clairfication about yesterday's journal entry- I was simply too tired to type. The two tigers sharks we saw - we watched underwater. They fed at the turtle and then decided we were in the way and turned their attention to us. For the reasons cited earlier, bad visibilty, mutiple sharks, and they were focused on us not the bait, we thought discretion the better part of valor and hauled buns...Like the energizer bunny, we didn't stop till we got to the boat. The bioat actual came and picked us up. We did get a nice close pass with good material of one of the sharks. Richard was filming while I watched his back with a broom stick to ward off any unwanted advances. While this may appear foolish behavior, it is possible by understanding what the sharks are doing, admitting it is impossible to predict what a shark will do, and by responding quickly to changes in the situation it is possible to control challenges and gather valuable documentary footage of shark feeding behavior.
The turtle tag data is in! The graph is below. This is obviously not a complete scientifc study as we have a sample populaton of one. You will remember we appear to have lost one tagged turtle, at this time - more to come. So we are in the early stages and the data is presented for popular review, enjoyment and education. (The team is on the island right now tagging another five turtles. Hopefully we will be able to re-find those turtles and down load the data from the tags).
This graph and data is copyright protected material like all other material on this web site. Please respect the copyright.
As you can see the graph reads over a 24 hour period and shows temperature (left hand vertical scale) and depth (right hand vertical scale) over time along the bottom. The tag attached to the underside of the carapace (shell) at the tail, was set to take readings every 20 seconds. The long and short of it is that we now have some new if not finally conclusive data about what female turtles do during their intranesting cycles, the fourteen day periods between their egg laying events. The ocean floor around Raine Island is over a kilometer deep, so we are all keen to find out how deep they actually dive. As you can see they can dive as deep as 30 meters (approx 100 ft.) and remain for as long as fifty minutes and it seems they do different types of dives during the day compared to night time.
This is just one of the projects being undertaken by scientists, here at Raine Island. The experiment is designed to try and find out where the turtles go during their internesting periods. This is the time they spend in the water after they leave the nesting beach, having laid a clutch of eggs, and before they return to lay another clutch. But these are early days and as more information is collected and analysed we will hopefully be able to better understand the life history of these fascinating animals.
Tomorrow we head out to see if we can locate the tagged turtles with the hydrophone and receiver. Could be interesting.
On the dive front the visibilty has been bad for a couple of days. The diving has been slow because of the visibility, which has suffered due to increased levels of plankton in the water which may, in part account for the the number of manta ray sightings our team has experienced on their dives. But, the diving was good enough this afternoon when I went deep and found an old admiralty anchor I had first found and then lost again back in early August during our first expedition. Richard wants to film the anchor as it no doubt dates back a long way. We tried to find it back in August but frankly we weren't looking deep enough. I am still working on the digital housing - along with all the other things going on and am confident that we are about there with the mechanics. It is just such a different housing from the housings I have used for so many years. A few images are enclosed.
Don't forget you can email us questions at
raineexpedition@netcarrier.com
Email Question Replies

Our team received the followings questions from people by email.
Q: Which are the most common barnacle species on these turtles? How frequent is their occurrence? and what other associations with invertebrates or algae have been observed?

A: The most common epibiont (commensals or things that live on sea turtles) is a barnacle called Chelonibia testudinaria. These barnacles only occur on sea turtles. While numbers of barnacles on individual turtles are not high, ranging from a few to several dozen, they are reasonably common, being recorded on perhaps 20% of the nesting turtles. Generally the turtles coming ashore to nest are very "clean". While some very light algal cover may be present no work is being done to describe the species.
Q: Where do the researchers say these nesting turtles spend the rest of there time when they are not nesting (how far do they migrate, where do they feed (other countries?))?

A: The turtles nesting here at Raine Island belong to the northern genetic population of green turtles in Queensland. (The southern genetic population focuses it's nesting in the Capricorn-Bunker Islands off central Queensland). When turtles finish nesting here they will return to their foraging areas which may be distributed either along the Queensland coast or in the island countries of Vanuatu, New Caledonia, Papua New Guinea, Western Papua and Indonesia. It is likely that some of these turtles will swim up to 2500 kilometers to get home! For a detailed description on-line you may want to log into the Great Barrier Reef Marine Park web page and check out their Sea Turtle info kit at.
We welcome questions about the work our team of scientists and film makers is carrying out here at Raine Island. Please remember that we will make every effort to answer all emails but due to time and technology constraints we ask that you keep your questions brief and simple.

Also, at this point, it is important to note that all data presented is preliminary and shared for the enjoyment and education of those "coming along" with us. It is not meant to be presented in a scientific format but more at the popular level as we hope to involve school children in our search for a better understanding of Raine Island and its wildlife.
Built on an Apple G4 Titanium Powerbook courtesy of Apple Computers Inc., Connected to the world by Iridium Satellite LLC and Digital eyes courtesy of Nikon - the new D100 digital camera, Captured on LexarMedia digital film.
© 2002, Paul Sutherland Photography LLC. All images and text on this and every other page on this web site are protected by US and international copyright law. No unauthorized use of any kind whatsoever is permitted.
Photo Captions:
• Turtle heads for water.
• Paul Sutherland at work on his Apple laptop.
• Oriental Sweet Lips.
• Moth - visitor from the mail.