Sea Turtles (Testudines) in the Canary Islands – Species & Facts
The turtles are an order of vertebrates that includes 341 species, 6 of which occur in the Canary Islands. There are sea turtles only on the Canaries. The Testudines live both in the water and on land. It is estimated that they have been living on earth for 220 million years. Many species are threatened by humans. In the Canary Islands, too, sea turtles are regularly saved from nets. Although some turtles live in the Canary Islands all year round, most of them pass by here during the summer months. This means that they can be seen on the large islands of Tenerife, Gran Canaria, Fuerteventura and Lanzarote as well as on the small islands of La Palma, La Gomera and El Hierro.
Description, Anatomy & Characteristics
Turtles are elliptical. The size varies depending upon kind between 10cm and 2.5m. In addition, they reach a weight of up to 900kg.
They can have the most different colours. From black, green, yellow to beige, brown or grey everything is represented.
The most striking feature of the Testudines is their carapace, which makes up for about 30% of the total weight. The carapace is divided into back and abdominal part and consists of massive bone plates. It is again protected by a leather-like skin or by a layer of hornshields.
Turtles have very good eyes. As they have four different colour receptors, they can partially see infrared and ultraviolet radiation. The lens of turtles is designed to compensate for the angle of refraction of the water, so they can see everything clearly even underwater.
Testudines sense of smell is also excellent. Sea turtles smell by chewing movements of the lower jaw and pumping movements of their neck. This allows them to recognise possible sexual partners and suitable soil for laying eggs.
The hearing of turtles is less good. They only hear sounds between 100 Hz and 1000 Hz. This means that they hear mainly deep vibrations.
Both cognitive abilities and the sense of orientation are extremely good. Some sea turtles travel tens of thousands of kilometres and then return to the place where they were born.
Habitat, Distribution & Occurrence
Apart from the sea turtles, there are also land turtles. Except in the polar regions, they occur worldwide and colonize various habitats. These include forests, swamps, deserts, semi-deserts, lakes, ponds, rivers, brackish water areas and oceans.
Unfortunately, their habitats are severely endangered by humans.
On the Canary Islands there are only sea turtles. A total of six species can be observed.
Biology & Feeding
Above water and under water Testudines are rather comfortable animals and move, if at all, mostly slowly away. However, sea turtles can also accelerate well when in danger.
Turtles do not chew their food but swallow it whole or tear off small pieces. They are not choosy on that occasion, however, they feed mainly on vegetable or meaty food. The feeding behaviour can change from young to adult animals. In any case, they need a lot of calcium to lay their eggs.
Some Testudines are also food specialists. For example, leatherback turtles mainly eat jellyfish.
Where to see sea turtles in the Canary Islands?
There are about 30000 loggerhead turtles on the Canary Islands alone. This makes them the most common representatives of their order in the Canaries, followed by the hawksbill turtle and the green sea turtle.
The dive site El Puertito on Tenerife is known for its tame turtles. These are probably loggerhead turtles. Since the bay is well protected from weather influences and the animals are also in shallow water, the place is also suitable for absolute diving beginners and snorkelers.
There are also kayak tours and whale watching trips, that visit these well known places.
In the harbour area of Morro Jable there is a sea turtle sanctuary. Here everyone can have a look at the beautiful animals. But please be quiet and don’t touch them! Admission is free, but you are always welcome to make a small donation so that the project can continue. Open from Monday to Friday, 10:00 to 13:00.
You can also observe the loggerhead sea turtle on Fuerteventura in its natural habitat, especially during the summer months. Their favourite place is the Sotavento beaches. Originally, the animals even nested on Fuerteventura. But these times are over due to the increasing tourism. But there is hope. A project is going on to bring them back, by putting eggs on protected beaches of Fuerteventura.
On Lanzarote you can see the ever popular animals e.g. at the dive site Playa Flamingo or on a boattrip in the marine reserve Chinijo.
Also on La Palma you can see the loggerhead turtle most often. They pass by here during the summer months and takes a short break. I could observe it myself at many dive sites, but mostly in the south, in Malpique or Las Cabras. But also in La Bahita, La Bombilla and Puerto Naos I could admire them.
Because of its marine reserve off La Restinga in the south of the island, El Hierro is a popular destination for divers. Two turtles have settled directly in the harbour of the small village. You also have the chance to watch them at the other dive sites.