03 Dec Tagging Turtles and other…
Celine van Weelden, WCA Intern
03/12/2016: Tagging Turtles and other Night Time Happenings
I had no idea what to expect as I climbed into the back of a small 4×4 at 7pm on a Friday evening. The 4 occupants of the car greeted me briefly before returning to their animated conversation in Portuguese. I gazed out of the window, wondering what the night had in store, as we bumped down the track through town and out onto the dark windswept beach.
I was lucky enough to be accompanying the local park rangers and turtle monitors who were getting a few days tagging and monitoring training from a couple of more experienced specialists before peak nesting season began.
‘Turtle season’ in southern Mozambique runs from the beginning of October till the end of March. Between October and December nesting females drag themselves onto the beach to lay their eggs and as of January or even late December, the hatchlings begin emerging and making their treacherous journey into the big blue. During this six-month period, local monitors patrol allocated stretches of coastline recording track and nest location and numbers and protecting the turtles, eggs and hatchlings from poachers.
When Angie moved to the area in 1999, she saw turtles come ashore to nest on a few occasions. When she was approached by a young Mozambiquan by the name of Oswaldo who was a student at UEM she jumped at the opportunity of supporting and initiating a long-term turtle monitoring project in Ponta. Later years found Dolphin Research Centre teaming up with local Mozambique organisations AICM, CTV and Mozambique turtle working group to further the monitoring. Together with All Out Africa and a number of volunteers, the project continued under the wings of Dolphin Research Centre until 2009, after-which management was taken over by the newly proclaimed reserve, who’s partnership with the PeaceParks foundation guaranteed greater coverage and more man-power.
When I first arrived at the end of September, I attended the annual turtle meeting with Diana. Here representatives of the turtle monitoring effort in the various bays along the coast came together to review the reports from the past year and discuss any changes or potential issues relevant for the upcoming season. The problem of a large number of eggs being consumed by a growing bush pig population further north in the Maputo region lead to the decision to control the population and cull repeat offenders where necessary. This lead to various anecdotes regarding other egg predation including an issue with a couple of honey badgers just across the border in Kosi Bay, one of the peak nesting zones in South Africa. Apparently one individual had managed to dig up over 50 nests in a single night! Not to mention controlling these creatures is no small task. Since they are protected, culling was not an option. They therefore had to be relocated to a distant part of the reserve, which had to be done using a specific kind of cage as they have been known to chew their way out of various materials!
The idea of signposting individual nests was also discussed. While this would make monitoring them significantly easier, it would not only be time consuming but could potentially attract unwanted attention to the location of the nests. Efforts to conserve the turtles in Mozambique began in the late 1990s when a couple of scientists started trying to research the local population using primitive and experimental tagging and monitoring. Since then, the number of turtles killed for their meat or shells as well as the amount of eggs collected, have decreased dramatically. After the partial marine reserve was declared in 2009 all these activities became officially illegal which served to further reduce occurrences to almost zero over following years. Today, anyone caught harassing a turtle within the reserve is liable for a large fine. A person found collecting eggs or killing a turtle or in the possession of turtle products can be arrested.
Besides poaching, there are other human activities that negatively impact sea turtles. Being struck by boats, overfishing and pollution are a few of the main threats. Injury and drowning due to entanglement in live or abandoned fishing gear is another major issue. Although fishing in the area is strictly regulated, I have collected bags of ghost gear off the local beaches which would have devastating effects if left to drift in the ocean. Hopefully through raising awareness within the local communities the damage caused by such threats will be reduced.
We had been driving for almost 20 minutes when a set of huge tractor-like tracks were illuminated by the jeep’s headlights. Marcus slowed down and cut the lights. It seemed we had found our first turtle. A couple of the main rangers set off on foot up the beach to investigate. I was only aware of one creature that was capable of leaving tracks that large. The rest of us huddled together waiting with bated breath. It didn’t take long. The cry ‘gigantia’ went up and I found myself jogging to keep up with the group of excited locals. Gigantic she was. The huge leatherback was already busy digging her nest. We stood watching in awe of her size and power. Miguel Goncalves, the reserve warden, explained how females enter a trance as soon as they start laying so as long as we didn’t shine bright light in her eyes she would not be disturbed.
Augostiho, one of the Ponta monitors, used a red head torch to check for tags. He found one on the front left flipper and the number was recorded in a data book. Marcos Pereira, a marine biologist from Maputo, collected a DNA sample with the help of colleague Cristina Louro. This sample would will be added to an extensive online database which is used in various studies on the species. Miguel had to straddle her in order measure the length and width of her shell. ‘Ovos’ someone exclaimed, and we all leant closer as the first of the 80 or so soft round eggs plopped into the sandy pit she had excavated.
About half an hour later she had finished laying and began to refill the hole. She moved the sand backwards with powerful swipes of her front flippers and packed it tightly into to place with her paddle like hind flippers. It was obvious that each movement was a huge effort. Her whole body jerked as she worked, her breathing was raspy and dry and a sticky liquid was dripping from her eyes. Every now and then she would rotate her body 45 degrees to the right or left churning up the sand in an effort to hide the exact location of her eggs. A light rain had begun to fall, drifting down onto the calm ocean. Eventually she seemed satisfied and slowly turned and to start the demanding descent towards the lapping waves.
The hardships these creatures face is phenomenal. After migrating from her feeding grounds to her nesting site and mating, she will drag herself up the beach on several different occasions to lay clutches of eggs. If she is not satisfied with the nesting site she will return to the ocean and look for another one. If the nest is too close to the water it risks being flooded or washed away. During this entire six-month period, she goes without food. If that is not self-sacrifice to ensure the survival of offspring I don’t know what is!
Early the following morning I squeezed onto the open back of a bakkie along with 8 or so monitors and rangers, a couple of turtle shells and enough supplies for another day of turtle patrolling. Holding firmly to the sides to avoid falling off the back; we set off north along the uneven sand with the wind whipping salty spray into our warm faces.
The drive all the way up the beach was stunning. Besides a few villages and areas of development the coastline remains almost completely untouched. We had stopped to take the GPS coordinates for at least 20 tracks by the time we arrived at the rangers’ base camp. A couple of simple rooms were surrounded by various canvas tents, a fire pit and a few hammocks crafted from upcycled fishing gear!
We were here to give a turtle monitoring presentation to the monitors working further up the coast. it was mainly a refresher as many of the monitors have been already working with the turtles since 2009. My Portuguese had improved enough to understand most of the content and even appreciate some of the jokes!
Five species of turtle can be seen in Mozambique. Of these only two nest along the southern coastline. The loggerhead, is much more common and can be identified by the 4 plates along each side of its carapace (shell). The leatherback (Dermochelys coriacea) nicknamed gigantia in Portuguese (for obvious reasons) is the largest living reptile. It can grow to 2.5 metres and has a distinct leather-like ridged shell instead of the usual plates.
Once the basics had been covered, Christina began to address the data recording. “Se nao se ve os ovos, e porque nao ha ninho” was a recurring theme. Unless the monitors actually witnessed the egg-laying, they could only mark down the location of the tracks, not a nest. This is crucial to maintain veritable data and was repeated multiple times and translated into local languages to ensure everyone understood. Having finished with the presentation there was nothing left to do except sit and wait for the tide to ebb enough for us to drive back along the beach.
we left the camp at 6pm with more people than we had arrived with packed into the back of the bakkie. Within a kilometre or so we’d found a loggerhead. She was still digging her nest so we had to wait while she completed the hole, and had laid her eggs as loggerheads are much more easily disrupted. The moment she had finished filling in and disguising her nest, everyone jumped into action. The procedure was the same as it had been with the leatherbacks. Within minutes we were finished and backed away to let slightly flustered lady shuffle for the waves. Little did we know this was just the beginning of what was going to be a long and busy evening.
Over the next 5 hours I became something of an honouree crew member. 11pm found me crouched next to the 10th loggerhead of the day, with the container for the DNA samples in one hand and trying to help disinfect the scalpel and cut with the other. Despite appearing clumsy on land, the sheer strength of some of these fully-grown reptiles, allows them to make a speedy return to the water after nesting when they want to. It took Christina along with two other rangers to hold down certain individuals to allow Marcus to cut a tiny DNA sample from a front flipper. This particularly energetic patient was obviously not at all pleased to be held up in such a manner, and we all received several flipper-fulls of wet sand for our efforts!
“that’s enough, I don’t want any more turtles!” Marcus laughed as we clambered back aboard for the umpteenth time. Luckily, it was. The stars sparkled, brightly in the darkness overhead and the calming crash of the waves lulled us into a contented silence; deep in thought about natural wonders we had just witnessed. We bumped along the last few kilometres without seeing any fresh tracks, making it back into Ponta just ahead of the incoming tide.