Fifteen different species of toothed whales from 3 different families can be seen in the coastal waters of La Gomera: Sperm Whales (Physeteridae), Beaked Whales (Ziphiidae), Dolphins (dolphins and other small toothed whales) and Oceanic Dolphins (Delphinidae).
1. Sperm Whales
Sperm Whales have been hunted all over the world for centuries. And mainly for ricino oil which is found in their enormous heads, rather than for their flesh. At first it was used as fuel for lamps and then to lubricate machinery and regarded as "liquid gold". Another lucrative product is oil of amber, a thick, lumpy substance harvested from the whales´intestines and used in the perfume industry. Even the whales´huge cone-shaped teeth (50 in the lower jaw) were initially a valuable source of income, carved and sold in the US as "Srimshaws". Nowadays they are on show in museums.
Despite being ruthlessly hunted and butchered for many years, the Sperm Whales did not become extinct. In the 1980s there were about 400,000 of them in the oceans of the southern hemisphere and approximately 300,000 in the northern hemisphere.
The Sperm Whale has a large, square head with a distinctive straight line running from the upper lip to the forehead which is approximately 1.80 metres high. However it is not usually visible because most of it is underwater. On the surface we can usually only see a long, dark shape in the water which looks a bit like a floating cigar. The best way of identifying a Sperm Whale is to watch for its distinctive blow which is angled forward and to the left, rather than being vertical as are the blows of most other whales. This is because the blowhole is situated at the front of the head and on the whale´s left.
Male Sperm Whales can be up to 18 metres in length, the females about 11 metres. Newborns are about 3.5 to 4.5 metres long and weigh approximately 58 tons. Their social structure is complex. Young Sperm Whales stay together in groups of up to 50 animals. When fully grown they join a group of about 10 females but in order to do so, they will normally have to challenge an older male. When an adult male loses his harem he generally becomes a solitary traveller or joins up with another or other males who have been humiliated in the same way. Considering that the Sperm Whale can live for 70 years, this group of "pensioners" is not a small minority.
2. The Pygmy Sperm Whale (Kogia breviceps)
They Pygmy Sperm Whale is usually no more than 3 metres in length, mainly dark grey with a lighter-coloured belly, a flat snout and lives mainly on squid, cuttlefish, crabs, prawns and small fish. Gestation lasts 11 months and newborns are approximately 1.2 metres long. When sexually mature, these whales may be up to 3.7 metres in length and weigh a little over 400 kgs. Not much more is known about them. In the past few years we have only seen them once in the coastal waters of La Gomera. The Dwarf Sperm Whale (Kogia simus) is another, though very similar to the Pygmy Sperm Whale, which inhabits remote waters and therefore has also not been studied very much.