Sea turtles hatchlings go straight to the ocean after hatching. They will return to coastal waters as juveniles to forage. Not much is known about the years in between these two events, which is why this period has been dubbed the “lost years”. One thing that is known is that when the hatchlings first reach the surf they swim out to open waters for several days on end during what is called the juvenile frenzy. One of the ways this was demonstrated in the 1970s was by having good swimmers follow the hatchlings out at sea. It is thought that after a certain amount of time, the great oceanic currents catch the hatchlings. New research carried out recently in Boa Vista, Cape Verde, confirms this hypothesis. The researchers followed hatchlings with a boat for up to eight hours and up to 15 km out at sea using acoustic nano-tags. Dr Rebecca Scott, the lead author of the study reports that “for years, people have always spoken about hatchlings being swept away in the currents, but this is really the first good, direct evidence for that happening.” The results of this study are valuable to help better understand the biology of sea turtles and to get more information about the “lost years”. This, in turn, will be vital to develop more efficient conservation policies to protect this endangered species.
Video courtesy of the New York Times – http://nyti.ms/1tyjsF1
It happened again: a nest in the hatchery emerged during the late afternoon! This is a rare occurrence as hatchlings usually emerge from their nest during the night.
Shortly after we finished two nest excavations in the hatchery, there was movement at the surface of a nearby nest. The sand was moving as if magically. Then, a little turtle popped his head out of the sand. He was soon followed by another, and then another. 62 little turtle hatchlings soon emerged from the sand and scattered out of the nest.
We collected all the hatchlings and brought them to the beach. We released them at the top of the beach and watched them all run energetically towards the sea. It was a really fun sight!
It is possible to adopt sea turtles at the SOS Tartarugas Conservation Centre. You can adopt individual hatchlings, entire nests, and adult nesters. Of course this is a symbolic adoption and you do not get to take the sea turtle home with you, but you would be surprised of how many times I have been asked things like: “What should I feed my baby sea turtle when I am back home?”
For example, if you adopt an adult nester, you can choose a name for your turtle and will receive a personalized Adoption Certificate. Your turtle will be tagged and you will receive her unique tag numbers. Every time your turtle comes ashore you will be informed by e-mail and will receive relevant information such as if she nested and how many eggs she laid!
If you are interested in adopting a sea turtle you can visit the SOS Tartarugas website. Adopting a sea turtle is a very nice gesture and can be a special present for a loved one! It is also a great way to show your support for the project and the conservation of loggerheads in Cape Verde.
The day after a nest hatches, nest excavations are carried out. This is done for two main reasons:
- it allows hatchlings that were unable to make it out of the nest on their own to be released
- it enables the calculation of the success rate of each nest
Not all eggs develop into fully formed live hatchlings. Sometimes eggs are infertile, sometimes eggs fail during development, and sometimes hatchlings suffocate at the bottom of the nest. This happens for nests in the hatchery and for nests incubating naturally on the beach. The success rate of a nest is given as the number of live hatchings out of the nest against the total number of eggs in the nest.
Quantifying the success rate of a nest can be very informative scientifically. As part of my research I am trying to see if there is a relationship between the success rate of a nest and environmental variables such as sand temperature and rainfall.
As well as being scientifically informative, a nest excavation is also an exciting time and attracts many tourists because of the live hatchlings that are excavated from the nests. The opportunity to see wild baby sea turtles is unique. They are quite an amazing sight!
Hatchlings usually wait for nighttime to emerge from the sand. The temperatures are cooler and they can reach the sea under the cover of darkness. Something quite unique happened yesterday at the hatchery: a nest emerged in the late afternoon!
First a hatchling popped his head out of the sand. Then a flipper. Then another hatchling showed his face. And another. And before you know it, dozens of little hatchlings were crawling out of the sand! It was very special to see.
The hatchlings were full of energy and scattered around the hatchery. We collected them, counted them carefully, and released them altogether afterwards. It is quite rare to see this happen during the day so everyone present felt very lucky!
Turtle nests are sometimes relocated to the hatchery. The hatchery is a place where the eggs are kept safe from predators and where they can incubate naturally. It is a pretty unique place, in that when you are walking around the hatchery you know that there are literally thousands of turtle eggs developing into hatchlings just under your feet!
Each nest is carefully labelled and the due date is recorded. Several days before the nest is due to hatch a circular cage is placed atop the nest so that when the hatchlings emerge from the sand they do not scatter everywhere. During the night, a ranger will check the nests every hour so that he can immediately release any hatchling that emerge from the sand. The hatchlings are brought to the top of a beach and are released. They then reach the sea on their own.
Sleeping in the hatchery and releasing the hatchlings is something that I have not yet done. Hopefully I can do this before the end of my stay!