The dwarf sperm whale is a small toothed whale found widely in temperate and tropical seas. It is distinct from the pygmy sperm whale.
It has a small, compact body and a small dorsal fin near the middle of its back. The back is blue-grey to brown, while the underside is paler.
Around Malpelo Island off Colombia, researchers detected a Dwarf Sperm Whale for the first time in the area by testing DNA traces in seawater. During a March 2018 expedition, they set 13 transects within about 2 km of the island and sampled water from 0–40 cm below the surface. Environmental DNA can reveal species from traces left in the water.
Whale DNA was detected on the same circular transect by two testing methods, and a mammal-specific test also detected it on another transect. The seawater sample provided the first record of a Dwarf Sperm Whale near the island. Repeated sampling can add distribution records for marine animals that are difficult to see at sea.
An extinction-risk assessment has not been added yet.
Seawater DNA provided the first detection of a Dwarf Sperm Whale around Malpelo Island. Repeated sampling in rarely documented waters, combined with visual survey records, can help build knowledge of where whales occur.