The Bold Loggerhead
Thierry Lannoy
September, 2009
We set sail this morning from the port of San Sebastian in La Gomera to work around the island.
We, the divers, will remember this port because of what we saw yesterday, and saw again today. At the end of the dive we started to come up to the surface when we saw a loggerhead sea turtle at 10 meters depth… the turtle reacted immediately: as soon as it saw us, it came swimming at full speed ahead, straight towards us.
It got so close to the cameras that we had no choice but to escape! I think it would have been great to see the Oceana divers chased by a hungry turtle! This lasted a few minutes and we were able to document this animal’s peculiar behavior.
Later, we were told that local divers feed this turtle regularly and the animal now associates divers with food. This reminds us that modifying the habits of wild animals is wrong: it distorts their behavior and gives the wrong impression of their true nature.
We sailed to the next dive site to work with the ROV and we passed closed to the coast of La Gomera Island. The cliffs and mountains offered an impressive site, with the towns hanging on the mountains along the coast.
After the dive with the ROV, we returned to port at the island of La Palma.
While we worked with the ROV, a Sei whale (Balaenoptera borealis) approached us.
Grand Canary
September, 2009
We are still in the southern islands. Today, we worked in front of Mogan again, protected from the trade winds.
Pitu had an intense day today piloting the ROV; we did three dives south of Grand Canary. We went down to 540 meters for the first time!
We had a few surprises. For starters, while the ROV was descending to approximately 410 meters, a thresher shark passed by us, directly in front of the camera. And as soon as we reached 540 meters…we were very surprised by the communities we identified. There were abundant sponges in a variety of colors on the rocky seabed, especially sponges in the shape of chupa-chups lollipops.
Oceana had already documented similar sponges in the Alboran Sea and in the deep waters of Galicia, possibly from the Stylocordila genus. But in this case, white lollipops were blended with blue ones, and we have yet to identify this species. It is surprising to see these colors at such depths.
And the last surprise was a solitary Venus flytrap anemone on the muddy seabed, which bears the name of the carnivorous plant it resembles. It looks like Ricardo made some kind of deal with the archipelago’s communities. Most mornings, he would wake up and say something like, “and today, it would be perfect if we found a…” and then... He would say a long name in Latin. That’s how our day started: we wanted to find a Venus flytrap anemone.
Cristina Fernández from the Oceanographic was with us. For years, she has been working on issues concerning conservation, science and the dissemination of information throughout the islands. She’s a diver, so she knows these areas quite well. But, looking at the screen, she couldn’t hide her surprise as the ROV descended to 500 meters right before her very eyes. She no longer has to imagine the scenery.
Glass Sponges
August, 2009
Today we changed our location and travelled south, to the Bocayna Strait, to carry out two dives with the ROV, one on each side of the strait.
We documented black coral, seaman’s hand coral, yellow coral, pandora and monkfish, although in this case, the most impressive site was a field of glass sponges (Asconema setubalense) at 376 meters depth.
These sponges, which can reach up to 1 meter in height, are usually found off the coast of Portugal, hence the name (Setúbal, Portuguese city). Recently, this species has also been identified in El Cachucho, a seamount off the coast of Asturias. There are also texts from 1933 that mention these sponges seen off the coasts of Africa (Morocco) and in Concepción Bank, although after that, they were not mentioned again.
As such, this is the first time this sponge has been identified in waters of the Canary Islands. Furthermore, Oceana previously documented this species in the Seco de lo Olivos seamount.
Voyage to the Canary Islands
August, 2009
The voyage aboard the Ranger has been stupendous. We sailed the whole way with sails, and we took advantage of the force 5 or 6 NW and NE winds.
First we passed the underwater mountains of Dacia and Concepción with the idea in mind of making some submersions with the ROV. However, in spite of the fact that sea and weather conditions have been good for sailing, the wind and some waves reaching up to 3 meters did not allow us to work with the ROV.
So... we continued on our course. We have been left no other choice than to leave these banks for another time throughout the campaign.
Of course, even though we were not able to document the animal life on this ocean bottom, surrounding the mountains, we saw a group of sperm whales, another group of striped dolphins and another group of Atlantic spotted dolphins, besides a turtle, many North Atlantic great shearwater, the odd European petrel and a shark. We were unable to identify this shark, but it appeared to belong to the genus Carcharhinus.