The short-finned pilot whale is usually found in groups of 10 to 60. It is a highly social animal, and larger herds numbering into the several hundreds have also been recorded. This species communicates through a variety of clicks, whistles, squeals, smacking, whining and ‘snores’, and it also uses echolocation (4) (7) (8).
The typical diet of the short-finned pilot whale appears to consist of squid and fish, as well as other cephalopods, such as octopuses (1) (4) (7) (8) (9). However, short-finned pilot whales have been reported to “harass” sperm whales and dolphins, so marine mammals may also potentially be included in their diet (4). This species usually feeds at night, making deep dives in search of prey (1) (7).
The short-finned pilot whale does not seem to have a typical breeding season, and has been recorded breeding and giving birth in winter, spring and autumn. The gestation period lasts for a little over a year, and female short-finned pilot whales give birth about once every three years (4) (8). Each female short-finned pilot whale will give birth to four or five calves during her lifetime (2). The newborn calf averages about 1.4 metres in length and weighs around 60 kilograms (2) (4) (8), and may be suckled by the female for at least 2 years (7).
The short-finned pilot whale lives in a ‘matrilineal’, or female-based society, and older females have been known to care for a calf that is not their own (4). After weaning, young male short-finned pilot whales may move to a new group, whereas females tend to stay in the group into which they were born (7). Herds of this species usually consist of a small number of reproductive adult males, sometimes only one, with a greater number of adult females of all ages and reproductive status, plus immature calves of both sexes (2) (7). The name “pilot whale” comes from an early idea that groups of these whales are piloted by a leader (6).
Female short-finned pilot whales reach sexual maturity at about 8 years of age, while males reach maturity later, at about 13 years. A typical male short-finned pilot whale will live for approximately 45 years and a typical female for about 55 years (2), although the female will usually stop reproducing after about 40 years old (7).