Pygmy Sperm Whale * Dwergpotvis * Kogia Breviceps

By Inwater Research Group - https://commons.wikimedia.org/w/index.php?curid=51511981

By Chris huh, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=2130192

Walvis Potvis

They are rarely seen at sea, therefore most of the information we have about them comes from studying stranded specimens.

The pygmy sperm whale is comparable in size to a lot of dolphins. They are roughly 1.2 m (3 ft 11 in) long at birth and reach a mature length of 3.5 m (11 ft). Adults typically weigh 400 kg (880 lb).

The "melon" is a body of fat and wax in the head that the pygmy sperm whale uses to concentrate and adjust the noises it emits.

By Kurzon - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=27491999

Although they typically live alone or in pairs, pygmy sperm whales have been observed in groups of up to six. While lengthier dives of up to 45 minutes have been observed, the average dive time has been assessed to be 11 minutes.

Uniquely, dwarf and pygmy sperm whales use a substance called "ink" to avoid predators in a way similar to squid. Both species can eject up to 12 liters of a dark reddish-brown fluid from a sac in the lower part of their body to frighten or deter possible predators.

Sources:

(*) https://en.wikipedia.org/wiki/Pygmy_sperm_whale
(*) https://www.inaturalist.org/taxa/41464-Kogia-breviceps
(*) https://animalia.bio/pygmy-sperm-whale