Many travelers to the Galapagos Islands hope to see a hammerhead or whale shark gracefully plowing the waters around them while they dive. And these Enchanted Isles are the perfect place to have this experience.
Sharks are of the elasmobranch class of fish, which also includes rays, skates and chimeras (ghost sharks). They have a cartilaginous (instead of bone) skeleton, five to seven gill slits on the sides of the head, and pectoral fins that are not fused to the head. Sharks are an ancient species, with their first ancestors appearing in the fossil record over 420 million years ago. Modern sharks emerged about 100 million years ago. With a few freshwater exceptions, all live in the oceans.
Sharks are a highly migratory fish, and with monitoring projects, their movements are just beginning to be understood. Not much is known about their actions in the Galapagos, though in recent years, exciting discoveries have been made about these giants of the sea in the islands.
Of the nearly three dozen types of sharks found in the Galapagos Islands, only twelve are very common residents or migrants. Of these, five are most often seen during snorkeling and scuba diving expeditions. If you want to see massive shark schools and are an experienced scuba diver, consider booking a seven- to ten-day liveaboard expedition to Darwin and Wolf islands.
Scalloped hammerhead shark
One of the Galapagos resident sharks many tourists want to see is the scalloped hammerhead. This unique-looking shark has a large, hammer-shaped head that is scalloped along the front edge. Its eyes are at either end of the “hammer.” It is silvery gray to grayish-brown, and white on the underside.
Scalloped hammerheads swim at depths of three to 182 meters (10-600 feet). They are migratory, moving on to the Coco Islands off the coast of Costa Rica. As well, in June they migrate in large schools to the northern Galapagos Islands. In 2017, a scalloped hammerhead shark nursery was discovered in the Galapagos.
Smooth hammerhead and great hammerhead sharks are rarely seen in the Galapagos Islands.
The scalloped hammerhead shark is the symbol of the Galapagos Marine Reserve.
- Scientific name – Sphyrna lewini
- Spanish name – tiburón martillo común
- Length – 1.5-4.2 meters (5-14 feet)
- Best islands to see them – Wolf and Darwin islands; also Gordon Rocks, north of Santa Cruz Island
- Best months to see them – December-May
White-tipped reef shark
The white-tipped reef shark is the most common shark species in the Galapagos Islands. These non-aggressive sharks are often found in shallow waters. They are slender and grey, with white tips on the first dorsal and upper caudal fin. Their snouts are rounded. The white-tipped reef shark feeds at night and rests during the day. They breed in the Galapagos archipelago.
- Scientific name – Triaenodon obesus
- Spanish name – tintorera
- Length – 1.4-2.4 meters (4.6-8 feet)
- Best islands to see them – Common throughout the archipelago; Las Tintoreras islets near Puerto Villamil, Isabela Island
- Best months to see them – Year-round
Black-tipped reef shark
As its name indicates, the tips of this shark’s fins are black. The upper body is greyish brown and the underside white. Its snout is blunt and rounded. The black-tipped reef shark prefers warm, shallow coastal waters. This reef shark is small and quite timid. It breeds in the Galapagos Islands, often giving birth in mangroves. It can be confused with the black-tip shark (Carcharhinus limbatus).
- Scientific name – Carcharhinus melanopterus
- Spanish name – tiburón punta negra de arrecife
- Length – to 1.9 meters (2 feet)
- Best islands to see them – common throughout the archipelago
- Best months to see them – year-round
Whale sharks are not only the largest of the shark species, but also the largest fish species – and not at all related to whales. On the back and sides, they are blueish-grey with white spots that are unique to each individual. White lines run between the spots. The underside is whitish. The broad, flat head has small eyes just behind the mouth.
Unlike most sharks, the whale shark eats primarily plankton and only occasionally small fish. It is seen at depths of two to 20 meters (6-60 feet). Even though it is not known to birth in the Galapagos Islands, recent investigations show that a large number of pregnant whale sharks spend time near Darwin and Wolf islands.
- Scientific name – Rhincodon typus
- Spanish name – tiburón ballena
- Length – 10-12 meters, maximum 18 meters (33-39 feet, maximum 59 feet)
- Best islands to see them – Wolf and Darwin islands
- Best months to see them – July-September
Galapagos shark can be mistaken for dusky shark or grey reef shark, but it does have several distinguishing features. Its snout is wide and round, and the tall pectoral fin is slightly rounded. This is one of the larger sharks you’ll see in the archipelago.
It is most commonly encountered in shallow waters (2 meters / 7 feet) along coral reefs and rocky bottoms. It can also be seen as deep as 80 meters (263 feet), though juveniles prefer waters less than 25 meters (82 feet). Despite its name, the Galapagos shark is found in both the Pacific and Atlantic Oceans. It owes its name to being first discovered in the Galapagos archipelago. It breeds in the Galapagos Islands.
- Scientific name – Carcharhinus galapagensis
- Spanish name – tiburón de Galápagos
- Length – 10-12 feet (3-3.6 meters)
- Best islands to see them – northern islands; also Gordon Rocks
- Best months to see them – year-round
Other sharks you might see in the Galapagos Islands during your underwater explorations are black-tip shark (Carcharhinus limbatus), silky shark (Carcharhinus falciformis) and tiger shark (Galeocerdo cuvie).
Threats to Sharks of the Galapagos Islands
Sharks inspire awe and even fear in many people. These masters of the sea, though, are very important for the health of ocean environments. They are at the top of the food chain, with only humans posing a threat to their existence. Sharks may be accidentally caught in fishing nets – though humans most prize their fins which are considered a delicacy and aphrodisiac in some Asian traditions.
Fishing within the Galapagos Marine Reserve is strictly controlled. Still, in August 2017, the Chinese ship Fu Yuan Yu Leng 999 was intercepted in the reserve with 6,600 near-extinct and endangered sharks from the Galapagos aboard. The 20-man crew was tried and convicted, resulting in four-year prison sentences and a multi-million dollar fine.
Another major threat to sharks in the Galapagos Islands is the El Niño phenomenon. When an El Niño develops, ocean waters increase. This warming means there is less food for ocean dwellers – not only for sharks, but also whales, marine iguanas and seabirds. This decreased food supply means less breeding and a decrease in population. If the El Niño is severe, populations may starve to death.
Shark Conservation in the Galapagos
Because the Galapagos Islands are vast and secluded, over thirty varieties of sharks find refuge here. In 2016, the Ecuadorian government declared 38,000 square kilometers (15,000 square miles) around Darwin and Wolf islands a marine sanctuary to protect the high concentration of sharks in that area of the archipelago.
Several Galapagos research projects, supported by the Galapagos National Park and international agencies like the Charles Darwin Foundation, are revealing more about these masters of the sea, and new species are still being discovered, as in 2012 when the deep-water catshark (Bythaelurus giddingsi) was caught.
A project funded by National Geographic is monitoring the movements of sharks. Scientists have found that some important shark species migrate between the Galapagos, Malpelo Island (off the coast of Colombia) and the Cocos Islands (off the coast of Costa Rica). A swimway sanctuary has been proposed for this area of the eastern Pacific. Another fantastic discovery of this project is a scalloped hammerhead nursery in the Galapagos Islands.
Galapagos Whale Shark Project (GWSP) has found that a high number of pregnant whale sharks pass through the archipelago, especially near Wolf and Darwin islands. In 2017, scientists successfully conducted ultrasounds on these females.
Non-scientists are also being called to action to protect sharks in the Galapagos Islands. Local educational programs are helping Galapagos residents to understand the importance of these creatures in maintaining the environmental health of the archipelago. As well, shark researchers are asking people like you to become citizen scientists to help monitor this species.
Close Encounters of the Shark Kind in the Galapagos Islands
Shark attacks in the Galapagos Islands are very rare – especially considering that tens of thousands of people snorkel, swim and scuba dive in the marine reserve every year. The reason attacks may be so unusual is that Galapagos seas still are very pristine, guaranteeing sharks plenty of food.
According to Shark Attack Data, only seven shark attacks in the Galapagos have been reported since 1954, none of which have resulted in death. Two involved fishing accidents and four attacks were against surfers. The species of shark is unknown in most of the incidences, though in two, the Galapagos shark species was involved. This is considered to be the most aggressive of the sharks found in the archipelago.
If any close encounter of the shark kind were to occur, the Galapagos National Park will investigate the situation and issue any protective measures needed. Tour companies may also temporarily substitute snorkeling with other activities, like panga rides or kayaking, in the affected area.
But what measures can you personally take while you are in sharks’ natural habitat? Here are a few tips from shark experts:
- Avoid splashing about in the water, both upon entering from the panga or while swimming.
- As much fun as it is to swim with sea lions, reconsider swimming near colonies during pupping season. Sharks hunt after the young sea lion pups, and might think your flipper is a fin.
- Avoid areas where there is fishing.
- Do not enter signed no-swimming areas.
- Avoid wearing shiny jewelry or a brightly colored swimsuit, as you may be mistaken for a fish.
- Do not enter the water if you are bleeding, have a wound or are menstruating. (Sharks have an acute sense of smell, and blood can attract them.)
Because of the Galapagos Islands’ pristine environment, you will undoubtedly fulfill your dream of seeing these graceful sea creatures during your Galapagos vacation.
Photo credit: Anthony Patterson