Pygmy sperm whale significant concentration of magnetite crystals, which suggests that "K. breviceps" can navigate by magnetoreception. Studies have also shown that compared to the sperm whale, the pygmy sperm whale brain has significantly fewer neurons, which may be connected to a decreased complexity in social interaction and group-based living. Like all toothed whales, the pygmy sperm whale hunts prey by echolocation. Sound produced for echolocation by many odontocetes come in the form of high frequency clicks. The frequencies it uses are mostly ultrasonic, peaking around 125 kHz. The clicks from their echolocation has been recorded to last an average of 600 microseconds.
Whale shark feeder, targeting concentrations of plankton or fish. It is able to ram filter feed or can gulp in a stationary position. This is in contrast to the passive feeding basking shark, which does not pump water. Instead, it swims to force water across its gills. A juvenile whale shark is estimated to eat 21 kg (46 pounds) of plankton per day. The BBC program "Planet Earth" filmed a whale shark feeding on a school of small fish. The same documentary showed footage of a whale shark timing its arrival to coincide with the mass spawning of fish shoals and feeding