Cetacean stranding in the context of "Dwarf sperm whale"

The pygmy sperm whale (Kogia breviceps) is one of two extant species in the family Kogiidae in the sperm whale superfamily. They are not often sighted at sea, and most of what is known about them comes from the examination of stranded specimens.

Pilot whales are cetaceans belonging to the genus Globicephala. The two extant species are the long-finned pilot whale (G. melas) and the short-finned pilot whale (G. macrorhynchus). The two are not readily distinguishable at sea, and analysis of the skulls is the best way to distinguish between the species. Between the two species, they range nearly worldwide, with long-finned pilot whales living in colder waters and short-finned pilot whales living in tropical and subtropical waters. Pilot whales are among the largest of the oceanic dolphins, exceeded in size only by the orca. They and other large members of the dolphin family are also known as blackfish.

Pilot whales feed primarily on squid, but will also hunt large demersal fish such as cod and turbot. They are highly social and may remain with their birth pod throughout their lifetime. Short-finned pilot whales are one of the few non-primate mammal species in which females go through menopause, and postreproductive females continue to contribute to their pod. Pilot whales are notorious for stranding themselves on beaches, but the reason behind this is not fully understood. Marine biologists have shed some light on the matter, suggesting that it is due to the mammals inner ear (their principal navigational sonar) being damaged from noise pollution in the ocean, such as from cargo ships or military exercises. The conservation status of short-finned and long-finned pilot whales has been determined to be least concern.

A drift whale is a cetacean mammal that has died at sea and floated into shore. This is in contrast to a beached or stranded whale, which reaches land alive and may die there or regain safety in the ocean. Most cetaceans that die, from natural causes or predators, do not wind up on land; most die far offshore and sink deep to become novel ecological zones known as whale falls. Some species that wash ashore are scientifically dolphins, i.e. members of the family Delphinidae, but for ease of use, this article treats them all as "drift whales". For example, one species notorious for mass strandings is the pilot whale, also known as "blackfish", which is taxonomically a dolphin.

In historical sources, it is not always clear whether a given cetacean washed up alive or dead, but the term "drift whale" focuses on the benefits of its carcass – meat, blubber, fat, and other products – to the people who claimed it. Nowadays, when a dead whale washes up on a beach, often the authorities are required to dispose of it as a potential hazard to human health, so the resource implications go the other way: a drift whale is no longer a benefit to a community, but an expensive disadvantage.