Where Man and Turtle Meet
By Awake! correspondent in Australia
THE best time to meet an untamed sea turtle is when she is laying eggs in her newly formed nest in the sand. So would you like to come with me while we visit Mon Repos—a mile-long [1.5 km] beach on the coast of Queensland, Australia’s sunshine state? Do not be concerned that you will be troubled by the burning subtropical sun, for our visit will be nocturnal. The best time for such a fascinating excursion is between eight in the evening and midnight.
It is preferable to go with a trained guide and a small group, for there are several dos and don’ts if we are to see and touch a large mother turtle. As we walk along the beach above the high-tide mark, the guide asks us to keep our flashlights off because light disturbs the turtles. And we are surprised at how well we can see the yard-wide turtle tracks in the sand even without lights.
Next, our guide gives us some interesting facts about the marine turtles in the area. There are six different species in Australian waters, but only four of these are found here at Mon Repos, which is the main nesting area along the Bundaberg coast. In order of prevalence, these four species are: loggerhead turtles (Caretta caretta), flatback turtles (Natator depressa), green turtles (Chelonia mydas), and leatherback turtles (Dermochelys coriacea).
Our First Sighting
There is great excitement when we spot a large turtle. She is one of the first kind we listed—a loggerhead. We watch quietly as she continues her crawl up out of the surf to above the high-water mark on the sand. When we at last move closer, we see that she has dug a saucer-shaped hole by scraping the sand and vegetation away from around her. This prevents grass from growing over the nest and trapping the hatchlings when they emerge in 7 to 12 weeks. She has also finished the pear-shaped nest by alternately scooping and flipping sand with her rear flippers—scoop right, flick left; scoop left, flick right. All of this takes about 45 minutes.
Up until now, she could easily have been disturbed and have returned to the water, but once she starts laying the eggs, we are allowed to touch her. The ranger shines a light on her, and we can take photos if we wish. The turtle continues dropping her eggs into the nest for 10 to 20 minutes, along with a clear, mucouslike fluid that protects the eggs from fungus and insects while incubating. Loggerhead turtles average 120 eggs the size of Ping-Pong balls per clutch—14 days apart several times per season—with two to four years between seasons.
When we actually touch the turtle, we are surprised how soft her skin is—a factor that makes turtle leather so desirable and endangers the existence of turtles. Her shell, or carapace, is made up of plates and is comparable to a backbone and ribs. Now she begins to cover her eggs. But since she has laid them close to the tide line, they must be relocated if they are to survive. This will be done by two members of the research team who have joined our group.
Tagging the Turtles
Our turtle is going to be tagged on one of her front flippers to assist in research about marine turtles. This is not an easy task in view of all the sand she is busily flipping everywhere. The tags are made from a noncorrosive titanium alloy. On the back side is an address, and it is vital to the research project that all sighted turtles be reported by number. Only when the turtle dies should the tag be removed and returned, together with details of the turtle’s location. On the front of the tag is the turtle’s identification number. Our turtle is T54239, but we decide to call her Tabitha.
Because Tabitha has not previously been tagged, it is likely that she has never nested before and could therefore provide some vital information to help enforce the protection of turtles and their eggs in the South Pacific. Now, in order to get this information, we witness minor turtle surgery right here on the beach! The procedure is called laparoscopy and is commonly used on humans. Tabitha is gently turned over and placed on a wheelbarrow gurney. We feel sorry for her and find that stroking her throat seems to calm her. Those are not tears we see, but it is a salt solution she excretes to wash sand from her eyes and dispose of excess salt that is a result of her drinking seawater. They are not associated with pain. Her skin is scrubbed above her lower flipper; then a tube is inserted through a small incision, and a little air is blown in. By looking at her ovaries, the researchers discover that this is her first reproductive season, and she has many more eggs ripening. All this information is recorded; then the air is released through a valve, and the incision is stitched.
After being turned back over onto the sand, Tabitha instinctively heads for the water. The waves wash over her and sweep a relieved Tabitha out to sea.
Relocating the Eggs
As we turn back, we see that the eggs have already been removed from the nest. After four hours the egg attaches to the inside of the shell and forms blood vessels. If they are turned after this, they will be ruined. At the rookery, usually two hours are allowed for the relocation process, and the success rate in relocating eggs is very high. The purpose of this is to protect the nest and eggs from water and erosion. The temperature of the sand determines the sex of the hatchlings. Most islands have cooler sands and produce mainly males, whereas the warmer sands of Mon Repos produce mostly females.
Hatchlings emerge from January until March. They scratch at their sand roof, causing the sand to sift in and raise them higher. If the temperature of the sand is not too high, they continue their journey out of the nest and scramble toward the sea. But their journey has only just begun. It is believed that it takes 50 years to reach reproductive maturity. Only a small percentage make it that far.
Man Must Learn to Care
Unfortunately, mankind’s carelessness and thoughtlessness are doing much to decrease the six known species of sea turtles. Plastic bags thrown into the sea are often mistaken for jellyfish and are eaten by the turtles. This blocks their digestive tracts and causes them to starve to death. Other rubbish may strangle the turtles. Even boat propellers may present danger if the navigator is not careful. Added to this are oil spills and toxic wastes that may wipe out entire coastal populations during a breeding season. And because a turtle must surface every 15 minutes for air, fishing nets that entangle a turtle may cause it to drown.
As more people become aware of these hazards and learn to take greater care of the environment, increased opportunities will undoubtedly come for man and turtle to meet—impressing and enthralling humankind with yet one more marvel of creation’s amazing reproductive cycle.
[Pictures on page 26]
Top left clockwise: minor surgery, returning to the sea, eggs being relocated, flipper being tagged