The reason why we can find these stable colonies of cetaceans in our waters throughout the year is especially due to three factors: Calm waters, an average water temperature that ranges between 18 and 20 degrees Celsius and a water depth which averages 1,500 meters between the islands of Tenerife and La Gomera and whose maximum depth is approximately 2,400 meters. All of these factors make these waters very rich in organic matter, fish, and -especially- squid and other cephalopods, also being able to find specimens of giant squid, which is the favourite food of the sperm whale (Physeter macrocephalus). The abundance of food, combined with the factors previously described, allows pilot whales (Globicephala macrorhynchus) and bottlenose dolphins (Tursiops truncatus) to live in our waters throughout the year, and for many years. In addition to these two species, which are commonly seen in these waters, we can also find some of the following specimens with a good amount of frequency: The sperm whale (Physeter macrocephalus); the false killer whale (Pseudorca crassidens); the tropical whale (Balaenoptera edeni); the common dolphin (Delphinus delphis), smaller than the bottlenose dolphin; the striped dolphin (Stenella corevalba), very easy to recognize because of its beautiful, dark, longitudinal lines; the rough-toothed dolphin (Steno bredanensis); Risso's dolphin (Grampus grislus); the bottlenose dolphin (Tursiops truncatus); the spotted dolphin (Stenella frontalis), of a size similar to the common dolphin but with a colour similar to the bottlenose when it is young. And, on some occasions, the blue whale (Balaenoptera musculus), the beaked whale (various species), and the killer whale (Orcinus orca) - up to a total of 26 species.