If you want to see Galapagos hammerhead sharks you will most likely need to get into the water. ... These sharks are most often found at a depth of three to 182 meters (10-600 feet), though they can dive deeper. Scuba Diving in Galapagos
The most common of the hammerhead sharks, scalloped hammerheads are a migratory species found in warm temperate and tropical waters of the Atlantic, Indian and Pacific Oceans. They can be told apart from their close relatives by the ‘scalloped’ front edge of their hammer-shaped head (which is called the cephalofoil). The cephalofoil has evolved to improve vision and to provide a larger area for the electroreceptors that the sharks rely upon for hunting prey on or under the sediment.
The Galapagos Marine Reserve (GMR) is one of the few places on Earth where scalloped hammerhead sharks can be seen gathering together in large schools of up to several hundred. The exact reason behind this schooling behaviour remains a mystery. In 2017, it was also found that scalloped hammerheads have nursery sites in the GMR.
Scalloped hammerhead sharks are listed on Appendix II of CITES meaning that all international trade of this species must be registered. Within the Galapagos Marine Reserve, scalloped hammerheads are protected by law and, in 2007, Ecuador issued two new decrees which established better controls
The formation of the islands around the “punto caliente” (hot point) of the terrestrial crust and its displacement to the east generates fascinating submarine geography that directly influences the unique ecology of the islands
The reserve is home to a unique combination of temerate and tropical water species due to its location at the meeting point of two currents: the warm Panama current coming from the northeast, and the cold Humboldt current that comes from the southeast.
This is the only place in the world where you can observe, for example, penguins swimming over corals. There are also two species of sea lions: one from the north and the other from the south. The deep Cromwell current is added to the mix, coming from the west, which rises when it meets the Galapagos platform, bringing with it enormous amounts of nutrients that generate an abundance of plankton and algae. Hence, the marine currents generate three sub-marine bioregions, or microclimates in one archipelago: the warm north side, the cold south-central side, and the nutrient-rich west side.
Additionally, the north-central area is home to a mix of waters, which according to some experts can be said to constitute a fifth bioregion, situated in the shallow areas between the Fernandina and Isabela islands.
The complex submarine geography combined with these oceanographic factors generate a high percentage (around 20%) of endemic species that include black coral of the Galapagos, the flightless cormorant and the 'canchalagua' (a mollusc). These waters are also an important site for migratory species such as marine turtles, hammerhead sharks, whale sharks, giant manta rays, and whales.
east and south coasts precipitate on sheer slopes that descend to over 3,000 meters.
The waters between the islands are shallow, less than 500 m deep. Towards the west, the oldest and most heavily eroded islands form the Carnegie submarine mountain range. This also generates great marine environmental diversity, affects the currents flow and water temperature.