Short Finned Pilot Whale

The **short-finned pilot whale** (***Globicephala macrorhynchus***) is one of the two species of cetaceans in the genus *Globicephala*, which it shares with the long-finned pilot whale (*G. melas*). It is part of the oceanic dolphin family (Delphinidae). It has a worldwide distribution with a global population of about 700,000, and there may be 3 or 4 distinct populations—two in the Pacific and one in the Atlantic and Indian Oceans. Its range is moving northward due to global warming. In the Pacific, males average 4–6 m (13–20 ft) and females 3–5 m (9.8–16.4 ft). It generally has a stocky build with black to dark gray or brown skin, and can be distinguished from its counterpart by shorter flippers, fewer teeth, and a shorter beak. It is thought to pursue fast-moving squid typically at a depth of 700 m (2,300 ft), but the maximum recorded depth is 1,018 m (3,340 ft). The short-finned pilot whale has been reported as being highly playful and social. It typically travels in pods of 10–30 members, usually family, but has been observed moving in groups of several hundred. Like killer whales, it has a matrilineal social hierarchy with an elder female at the head and a sizable post-reproductive lifespan. It is polygynous; females often outnumber males 8:1 in a pod. Pods are known to mass strand, possibly due to sheer accident, biosonars confused by geomagnetic anomalies, injury from loud military sonar, or disease. It was historically whaled, and is still whaled today by Japan and the Lesser Antilles, but it is protected by several international treaties.

Short-finned pilot whales are black to dark gray/brown, with a thick tail stock, fluke with sharply pointed tips, bulbous head, and a broad, sickle-shaped dorsal fin. Coloration typically includes light grey to white areas such as a saddle patch behind the dorsal fin, a light grey or white anchor-shaped patch under the chin and belly, and a blaze marking behind the eye. These traits, however, can vary between populations. For example, two distinct forms are described from on the Pacific coast of central Japan: the Shiho morphotype is the larger of the two–females 4–5 m (13–16 ft), males 5–6 m (16–20 ft)–and has a white dorsal patch and round melon, while the Naisa type is smaller–females 3–4 m (9.8–13.1 ft), males 4–5 m (13–16 ft)–with a characteristic flattened or squarish melon and a darker, indistinct saddle patch. When they are born, short-finned pilot whales weigh about 60 kg (130 lb) at a length of 1.4–1.9 m (4 ft 7 in – 6 ft 3 in).

Long-finned and short-finned pilot whales are often hard to tell apart. However, as their names indicate, short-finned pilot whale flippers are shorter than those of the long-finned pilot whale, measuring about 1/6th of the body length. Short-finned pilot whales also have fewer teeth – 7–9 in each row – and a shorter and broader rostrum with a premaxilla that covers more of the maxilla. Both species exhibit sexual dimorphism and have similar lifespans of about 45 years for males and 60 years for females, with long-finned pilot whales being generally larger than short-finned pilot whales. The two species have limited overlap worldwide; long-finned pilot whales are found in cooler temperate waters, while the distribution of short-finned pilot whales is largely tropical and subtropical.