May 27, 2021, 02:32 PM
A fin appears in the infinite turquoise blue. When it approaches the boat, the shark is caught. It will be a short capture. Soon it will return to the waters with a chip that will allow science to track one of the emblematic species of the Galapagos Islands.
“See? There!” exclaims Alberto Proaño, pointing to a shark attracted by a bait thrown from the boat. This 34-year-old biologist casts his line. The hook is filed so as not to injure the fish. A swooping pelican snatches the bait. The shark is gone. The wait resumess under the relentless sun that falls on these volcanic islands of the Pacific, 1,000 km off the coast of Ecuador. An hour passes. Another shark bites but manages to flee.
The engine starts and the boat heads to another area. Beneath the surface there is a shadow. Alberto casts his line again. “I have it!,” he blurts out after several attempts. He lets the animal come and go “to tire him out.” Then, with his hands protected by gloves, he pulls with all his might and brings it closer to the boat.
The Galapagos, named after the giant tortoises that inhabit them, are still an open-air laboratory, the same one that the English naturalist Charles Darwin used for his theory of evolution.
Its waters, rich in nutrients thanks to the confluence of four hot and cold currents, are home to more than 2,900 marine species, 25% of which are endemic.
The animal fights. The boat rocks. The captain and his assistant counterbalance to starboard. Two other guards from the Galapagos National Park (PNG) come to the rescue: the shark is finally tied up with ropes as soon as it is taken out of the sea. Marking begins. “You have to be very fast because a shark cannot be more than a few minutes out of the water,” Alberto tells AFP.
Crouching over the rail, he indicates the measurements: a female 2.30 meters long, about 150 kilograms, about 15 years old. A beautiful specimen of the Galapagos shark (Carcharhinus galapagensis), one of the 36 species that inhabit the archipelago.
With a quick flick of the scalpel, the biologist takes a skin sample, fixes a numbered yellow plastic rod, and inserts an electronic chip under the thick dermis. Then, very gently, the shark is released from its bonds. In a few seconds, the fin disappears. Rubi Cueva, a 23-year-old intern, takes notes of everything in a log.
“My dream is to also study the whale shark,” explains this young woman from Galapagos who is studying environmental management.
The task of monitoring and marking species, carried out by the PNG and other scientific organizations such as the Charles Darwin Foundation (CDF), aims to carry out analyzes and provide the animals with a unique international code.
In some cases they use satellite tracking beacons. It is about determining the population, habitats, food, migration routes, etc.
“This study allows us to know what part of the year or how long they stay in certain areas,” adds Alberto, happy to have been able to mark a second specimen that day. The PNG has carried out more than 300 trips to the sea in order to identify the birth areas of sharks or mark adults.
Another mission, the same week, will generate less adrenaline but will be no less challenging. At dawn, Alberto and Jennifer Suárez, 33, also a biologist and park ranger, leave with their team.
Search of the day: sea turtles. From the boat you can see dozens of them frolicking in the waves. But the breakers discourage you from getting close. The anchor will be launched later, in an accessible cove on Floreana Island. They will continue for two hours walking with difficulty between rocks of black lava plates, where marine iguanas bask.
Finally, the reward awaits on the beach: five languid turtles. “Don’t let them get away,” Jennifer recommends.
Each is assigned one and, at the signal, they start running across the white sand. The turtles crawl frantically, determined to reach the clear water. But, carefully, they are immobilized between the knees, which hold their shell firmly while the hands cover their eyes to calm them.
The biologists then proceed to take the samples and mark them. More than 18,000 turtles have been identified since 2002. Some have been detected in Costa Rica, Peru, and Mexico.
“We have several monitoring programs for emblematic species to know their population (…) what threatens them, what affects them,” Jennifer explains. Because the objective, he emphasizes, is “to generate data that allow their protection” with sharks, but also sea lions, corals, iguanas, all the species that make Galapagos an exceptional site, classified as the natural heritage of humanity.
Read the original coverage from AFP via El Tiempo at https://www.eltiempo.com/vida/medio-ambiente/galapagos-rastreo-de-tiburones-y-tortugas-que-preserva-la-vida-silvestre-591664
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