The Sharks Of The Galapagos Islands

The marine wildlife of the Galapagos archipelago is considered some of the most biodiverse on the planet. Among the vast array of marine animals are 32 of the world's 400-plus species of sharks. In fact, the waters that encircle the northwest of the chain, around Darwin and Wolf Islands, are so rich with these intriguing and much-maligned creatures it's been officially designated as the densest population in the world.

For those fortunate enough to travel to this fascinating archipelago to explore on a Galapagos cruise, understanding something about the presence of the shark species will provide a wider contextual view of the unique marine life.

The Sharks of Galapagos

The most common of all the species found in the waters surrounding the islands are the Scalloped Hammerhead, Bullhead and Whale sharks.  

The Whale Shark is so named for its imposing size and is known to grow up to an astounding 18 metres in length, although the average size is more like 12 metres. Weighing up to 15-20 tonnes, these ocean giants feed on plankton, vacuuming up vast amounts of water through their mouths and filtering it through their gills, in an ingenious and surprisingly delicate method called filter feeding.

At the other end of the size range, the Bullhead Shark is the smallest species of the region, only growing to about a metre in length. It can be identified by its small stature and unusual spotted markings on its back. This species is the one that scientists know least about, due to its small range that only extends throughout the archipelago and parts of the west coast of Peru. In fact, although a research project is currently underway, it's yet to be determined if the Galapagos species is separate to the Peruvian one.    

Named for its highly distinctive hammer-shaped appearance, the Scalloped Hammerhead Shark can grow to around four metres and travels the waters around Wolf and Darwin Islands in large schools (up to 100 individuals) – one of the few species to display this social behaviour. The unusual side placement of its eyes affords it a very wide angle of view and excellent opportunities for spotting prey in the surrounding waters, although the downside is a blind spot directly in front of the head. The species feeds on small fish and invertebrates, but will also occasionally dine on smaller sharks. 

Threats and Conservation

Along with the perils that come with human intervention, including illegal fishing of the archipelago's waters, the population is under threat from global climatic influences, decline of food sources and their own shortcomings in terms of slow maturation and breeding.

Explore on a Galapagos Cruise and Aid in Conservation

Thankfully, there are numerous conservation efforts in place to help protect the continued survival of the shark population of the Galapagos Islands and, indeed, throughout the world. In addition to education, memberships and fund raising initiatives (including hammerhead adoption programmes), ecotourism (bringing visitors through on Galapagos cruise itineraries) is helping to raise awareness of the threats that the species are facing.

Author Plate

Marissa Ellis-Snow is a freelance nature writer with a special interest in the unique wildlife of the Galapagos Islands. Marissa chooses the expert-led Galapagos cruise itineraries organised by Naturetrek, which have brought her unforgettable sightings of a wide range of wildlife in one of the most spectacular regions on Earth.