NIGHT MAGIC: Dusk Till Dawn On Our Beaches
To say there is naïveté surrounding what happens on our beaches at night from April to early November is an understatement. This article is meant to explain what the night magic is all about.
Night Magic and the people in chartreuse T-shirts
The Guardians of Akumal’s Turtles is a group of residents who volunteer for and work in collaboration with CEA (Centro Ecológico Akumal), with a mandate to ensure the safe nesting practices of sea turtles. During the day you can spot the Guardians by their bright chartreuse T-shirts walking the beaches as the sun is rising and again near supper time. When you are asleep, Guardians patrol until early morning in black shirts with red flashlights to see by, in hopes the subdued light will avoid startling the mother turtles.
Student volunteers and tourists visiting for extended stays are trained and work on the beaches hand-in-hand with the Guardians, who in turn work alongside with the program coordinator and tortugueras (highly trained and experienced marine turtle technicians and the coordinator). Everyone is equally invaluable in the effort to save the turtles!
Guardians and volunteers have gone through online and practical beach training, are tested, and are expected to follow strict protocols. Each has photo identification showing approval by CEA to be on the beach working with the turtles. They spend countless unpaid hours each week for six months of the year, with work approved and monitored by CEA’s marine biologists, tortugueros, and federal government officials.
During the 2020 season, during the height of the Covid-19 pandemic, Guardians (then called Voluntourists) stepped in when the government entities shut down. They worked day and night to conserve and protect the mother sea turtles and their hatchlings.
What happens at night?
Breeding female turtles exit the sea slowly and silently, lumbering up the beach to begin their search on land for exactly the right place to nest — they seek a dark, quiet, unobstructed location to begin the process of laying their eggs. This is why having outside lights out, curtains/shades pulled, beach furniture moved, and obstructions, including people, off the beach from 9pm to 5am is so important. These restrictions are federally
mandated by SEMARNAT NOM 162 and this year are supported by the municipality of Tulum.
A Green turtle (Chelonia mydas) likes to build a nest in a spot that is high up on the beach. Once chosen, the site is prepared by digging a cama, or bed, to accommodate her large body. She does this by throwing sand with all four flippers. These turtles like a bed that is 60 cm (24″) deep.
Once satisfied, she will begin digging the chamber. It will have a long, thin opening about 15cm (6-8″) in width and 30cm (12″) in length. She will form the bottom of the chamber into a bowl with the entire nest eventually shaped like an upside down lightbulb from top to bottom.
Press Link: Video A – Digging the chamber
In Video A you can see a turtle using its hind flippers like shovels to scoop out sand and deposit it in piles on either side of the hole. If the sand is too dry the hole caves in, causing her to abandon the effort. Sometimes the issue is rocks, but for the turtle in the video, the problem is roots from a nearby palm tree — you can hear the sound of her flippers trying to grasp the sand, but instead hitting roots and coming up empty handed, or empty “flippered”. When she realizes the problem, she leaves to find a more desirable location. In the morning you will see huge holes where abandoned nest attempts have occurred.
Once she found a suitable spot, she rebuilt the cama and chamber, and began resigning the nest. She reaches down, alternating her hind flippers, digging deeper until she can no longer reach the bottom — that is when she knows the chamber is deep enough. It will eventually be 50-60 cm (20-24″) in depth and width.
Next, she lowers her hind end and settles in. It is now that she enters a serene state and lays 120-200 eggs (Green turtle) and 80-120 eggs (Loggerhead turtle). See Video B of eggs being dropped.
Press Link: Video B – Laying Eggs
Once the last egg is deposited, she moves sand with her hind flippers to fill in the nest. In Video C, you can see her tamping down the sand to compact it.
Press Link: Video C – Compacting the nest
Next, sand begins to fly (see Video D) and this is when Guardians know to move out of the “splash zone” as rocks are often hurled backwards by the turtle’s strong flippers. She moves an incredible amount of sand creating a large mound on top of the nest.
Press Link: Video D – Cama and Berm
This process causes her body to move forward sometimes 2.5 – 3 m (10 – 12′), and eventually no more sand is available for her flippers to move. With front and back flippers flailing, and chest resting on a berm, she realizes she has covered her nest with a sufficient amount of sand. Green turtles can take 2-3 hours to complete this process; Loggerhead turtles (Caguama caguama) are less particular about location and depth of chamber and are usually are done in 1-2 hours.
With the nesting process complete, she begins her slow retreat to the sea.
Press Link: Video E – Out to Sea
During the nesting process, pertinent information is recorded for the biologists — measurements, identifying marks, tag number, and species. Nests are marked with white stakes recording the beach, nest number, and species of turtle.
Please do not move the white stakes as it would make finding these nests, and consequently saving the babies, a nearly impossible task!
Nests are continually monitored. By knowing the exact date of laying, the approximate date the baby turtles with hatch (45-60 days depending on species) can be determined. This year with the problem of sargassum, black crates are placed on top of impending hatches to prevent babies from running to the sea and getting stuck in the seaweed. A large rock is placed on top to keep the crate in place.
When a hatch occurs, babies are collected in green plastic bins and released into the ocean that night, or within 24-48 hours, in a sargassum free location. Getting stuck in the seaweed would leave them vulnerable to attack from birds or dying from the scorching sun — either way, few to no babies would survive.
People have asked such questions as, “Why are you stealing the turtles?”
Human interference by certified members of CEA is necessary to ensure that the highest number of baby turtles reach the sea safely — it is not theft, it is a rescue, sanctioned by CEA and the Federal Government!
The black crates are also useful in limiting on-land attacks by mapaches (raccoons) who like to eat the baby turtles as they emerge from the nest. The heavy rocks on top of the black crates prevent the mapaches from removing the crate and getting at the nest. Holes on the sides of the crates are covered with rocks to thwart these baby turtles, who can be little escape artists, in their effort to get to the sea. It is imperative that the black crates, the rocks on top and at the sides, are not moved.
Without the black crates mapaches would dig into nests to get at the eggs. When there is evidence of this occurring, a metal grid is buried 10 – 15 cm (4 – 6″) into the sand with rocks on the corners.
If mapaches have dug up a nest too early, babies are collected in the green bins and kept in a safe location until they have gained enough energy to be released. The babies that have not been dug up will remain in their nest with a black crate on top to ensure mother nature can continue her work, but with continual monitoring to guarantee a safe release. See Video F below of a baby emerging from the sand.
Press Link to see Video F: Video F – Emerging
What do you do if you see a mama turtle or a nest hatching?
Find one of the Guardians or volunteers on the beach and tell them. An alternative is to inform a security guard nearby who will contact the right people. Or you can contact the Emergency Turtle Phone Number at 984-280-3798.
Please follow CEA’s checklist for the best way to help nesting turtles.
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