Pilot whales are cetaceans (whales and dolphins) belonging to the genus Globicephala. There are two species — long-finned pilot whales (Globicephala melas) and short-finned pilot whales (Globicephala macrorhynchus). The two are difficult to tell part at sea. Analysis of the skulls is the best way to distinguish between them. Combined the two species range nearly worldwide, with short-finned pilot whales living in tropical and subtropical waters and long-finned pilot whales living in colder waters. Pilot whales are among the largest of the oceanic dolphins. Only orcas are bigger. They and other large members of the dolphin family are also known as blackfish. [Source: Wikipedia]
Pilot whales feed primarily on squid, but they also eat large demersal fish such as cod and turbot. They are gregarious and often remain with their birth pod throughout their lifetime. Short-finned pilot whales are one of the few mammal species in which females experience menopause. Humans and orcas are the only other known animals whose females go through it.
The animals were named "pilot whales" because pods were believed to be "piloted" by a leader. They are also called "pothead whales" and "blackfish". The genus name is a combination of the Latin word globus ("round ball" or "globe") and the Greek word Kephale ("head"). Fossils of an extinct relative, Globicephala baereckeii, have been found in Pleistocene Period (less than two million years old) deposits in Florida. Another Globicephala dolphin was discovered in Pliocene Period (5.4 million to 2.4 million years Pliocene strata in Tuscany, Italy,
Pilot whales are infamous for stranding themselves on beaches. The reason behind this is still not completely understood, but damage to the mammal’s inner ear (their principal navigational sonar) by ocean noise-pollution from cargo ships or military exercises may play a part.
Websites and Resources: Animal Diversity Web (ADW) animaldiversity.org; National Oceanic and Atmospheric Administration (NOAA) noaa.gov; Fishbase fishbase.se; Encyclopedia of Life eol.org; Smithsonian Oceans Portal ocean.si.edu/ocean-life-ecosystems ; Monterey Bay Aquarium montereybayaquarium.org ; MarineBio marinebio.org/oceans/creatures
Killer Whales Flee Pilot Whales Near Iceland
Killer whales are arguably oceans’ No. 1 predators. But in Iceland, they are known to flee pilot whales. Marina Wang wrote in Hakai Magazine: In 2015, out on the choppy waters off southern Iceland, Filipa Samarra and her research team were eavesdropping on a group of killer whales. She listened as they pipped, squealed, and clicked when suddenly her ears were filled with high-pitched whistling. “Then the killer whales just went silent,” says Samarra, a biologist and lead investigator of the Icelandic Orca Project. As the whistling grew stronger a group of pilot whales came into view, and the killer whales seemed to turn and swim away. “It’s quite unusual because the killer whale is this top predator,” says Anna Selbmann, a doctoral candidate at the University of Iceland who is supervised by Samarra. “It’s very unusual that they’re afraid of anything—or seemingly afraid.”[Source: Marina Wang, Hakai Magazine, Smithsonian magazine, September 27, 2021]
“Interactions between killer and pilot whales have only been scientifically documented a few times, and Samarra is among the first scientists to have observed this behavior in Iceland. Since the 2015 encounter, she’s seen similar interactions around 20 times. Selbmann says in the majority of the interactions documented around Iceland, killer whales seem to avoid pilot whales. Occasionally things will get heated and the pilot whales will chase the killer whales at high speeds, with both species porpoising out of the water. “One of the big questions that we have is understanding the variability,” says Samarra. “We don’t really understand what are the contextual factors that drive their response being different sometimes.”
Previous research offers up two possible explanations for what the researchers were seeing. One, the killer whales and pilot whales were competing for prey. To Selbmann, this is possible but unlikely, because these Icelandic killer whales mostly eat herring, while pilot whales in the area are thought to mostly eat squid. “The other theory is that it’s anti-predator mobbing behavior,” explains Selbmann. “A lot of animals mob their predators to rob them of the element of surprise. For example, meerkats will throw sand at snakes.” But even this explanation isn’t ideal, Selbmann says, considering the killer whales aren’t known to eat the smaller pilot whales. “They’re not really a threat to pilot whales,” she says. But Selbmann says it’s possible that the pilot whales didn’t know the killer whales weren’t a threat. In other parts of the world, killer whales do feed on smaller whales such as minkes, belugas, and narwhals, and are even known to chase down larger baleen whales. Perhaps the pilot whales are viewing them as a threat, and responding accordingly.
Steve Ferguson, a marine mammal ecologist at the University of Manitoba who is not involved with the research, says that the sightings are unusual because in so many other places killer whales are a top predator, and other smaller cetaceans tend to avoid them. However, there have been a few accounts of smaller prey species attacking the killer whales back. Researchers are beginning to pay more attention to the unusual interactions between different cetacean species, Ferguson says, noting which are capable of defending themselves against attack, and which become aggressive toward predators. Already, scientists have noticed other odd cases—such as how humpback whales seem to defend other whales against killer whale attacks.
To gain insight into what could be driving the interactions, Selbmann and Samarra are performing acoustic playback experiments. Previous research conducted in Norway showed that when scientists played the sound of killer whales to pilot whales, the pilot whales swam straight toward the sounds and swarmed the researchers’ boat. “Now we want to test the reverse,” says Selbmann. “Are the killer whales avoiding the pilot whale sounds?” Selbmann and Samarra spent the summer of 2021 broadcasting pilot whale recordings at killer whales equipped with tracking tags. So far they’ve conducted their experiment on four killer whales, and while the pilot whale calls didn’t immediately scare them off, a few of the killer whales did swim away. But Samarra cautioned it’s difficult to know what’s really going on without a closer analysis. “It seems something has changed in this ecosystem,” Sarmarra says.
Long-Finned Pilot Whale
Long-finned pilot whales (Scientific name: Globicephala melas) are one of two species of pilot whale, along with short-finned pilot whales. In the field and at sea, it is very difficult to distinguish between the two species, which differ only slightly in physical size, features, coloration, and pattern. Long-finned pilot whales and short-finned pilot whales (Globicephala macrohynchus) are the only two species of toothed whales that belong to the genus Globicephala. [Source: NOAA; Julianne Preston, Animal Diversity Web (ADW) /=]
Long-finned pilot whales are very social, living in large schools of hundreds of animals separated into close-knit pods of 10 to 20 individuals. This structure made them easy targets for whaling in the 19th and 20th centuries. Whalers would drive and herd pilot whales together into tight groups to harpoon them, hunting them for their meat, oil, and blubber. Females live longer than males. The average lifespan of females is 63 years, though they are only able to give birth until age 40. Female short-finned pilot whales go through menopause much like human females do. Males have a higher mortality rate then females and their average lifespan is 46 years.
Long-finned pilot whales have been and still are hunted for its meat by humans, especially in the Faeroe Islands. They don’t appear to be threatened or endangered but information about their numbers and populations is lacking. They are listed as “Data Deficient” on the International Union for Conservation of Nature (IUCN) Red List. The Convention on International Trade in Endangered Species (CITES) places them in Appendix II, which lists species not necessarily threatened with extinction now but that may become so unless trade is closely controlled. Population declines have documented in many populations. A subspecies recognized from Japanese waters became extinct by the 12th century. Threats include entanglement, disease, chemical contaminants and ocean noise. Long-finned pilot whales can become entangled or hooked in fishing gear, either swimming off with the gear attached or becoming captured in the gear. Morbillivirus has affected pilot whales in the North Atlantic and certain strains of the virus may be native to specific areas. Pollutants and various contaminants in the marine environment have been found in their blubber. Contaminants enter ocean waters and move up the food chain and accumulate in species such as long-finned pilot whales.
Historically, whalers benefited from pilot whales’ strong social structure and would drive and herd them together into tight groups during hunts. In the 19th and 20th centuries, American sperm whalers in the North Atlantic harpooned them, while a drive fishery in Newfoundland targeted them for meat, blubber, and oil. Drive fisheries for this species also historically occurred in the Falkland Islands, Greenland, Iceland, Norway, Scotland (Orkney Islands and Hebrides Islands), and the United States (Cape Cod, Massachusetts). Currently, shore-based hunters in the Faroe Islands (Denmark) continue to directly target long-finned pilot whales. [Source: NOAA]
Pilot whales are strong, aggressive and smart predators — the one species able to give orcas (killer whales) a run for their mony but unfortunately they are known mainly for their mass beachings.
Long-Finned Pilot Whale Habitat, Feeding and Where They Are Found
Long-finned pilot whales prefer deep temperate to subpolar oceanic waters, but they have been known to occur in coastal waters in some areas. They are native to the Indian Ocean, Atlantic Ocean and Pacific and Mediterranean Sea and found in water temperatures ranging from 13º to 30º Celsius (55 º to 86º F). They have amazing diving abilities. They are able to dive to depths of 1,800 meters. (5,900 feet).
Larger groupings of long-finned pilot whales have been documented on the continental edge and slope, depending on the season. This species has been described as "anti-tropical." Three distinct populations or subspecies of long-finned pilot whales are recognized: Southern Hemisphere, North Atlantic, and an unnamed extinct form in the western North Pacific. In the Southern Hemisphere, their range extends from 19° S to 60° S, but they have been regularly sighted in the Antarctic Convergence Zone (47° to 62° south) and in the Central and South Pacific as far south as 68° south. They have been documented near the Antarctic sea ice and associated with the colder Benguela and Humboldt Currents, which may extend their normal range, as well as the Falklands.
The southern subspecies range includes Cape Province, South Africa; Chile; southern Australia; New Zealand; and Sao Pablo, Brazil. In the Northern Hemisphere, their range includes the U.S. east coast, Gulf of St. Lawrence, the Azores, Madeira, North Africa, western Mediterranean Sea, North Sea, Greenland and the Barents Sea. In the winter and spring, they are more likely to occur in offshore oceanic waters or on the continental slope. In the summer and autumn, long-finned pilot whales generally follow their favorite foods farther inshore and on to the continental shelf. [Source: NOAA]
When feeding, long-finned pilot whales routinely dive to depths of about 610 meters (2,000 feet) for 10 to 16 minutes to feed on fish (such as, cod, dogfish, hake, herring, mackerel and turbot), cephalopods (such as, squid and octopus) and crustaceans (such as, shrimp). Most feeding occurs at night in deep water between depths of 200 and 500 meters (650 and 1,650 feet). Like other members of the delphinid family, long-finned pilot whales echolocate when foraging for prey. [Source: NOAA]
Long-finned pilot whales eat around 34 kilograms (75 pounds) of food a day. Squid, such as longfin inshore squid (Logio pealei) and northern shortfin squid (Illex illecebrous), mackerel, Atlantic herring, cod, and turbot are also are favorite foods. Pilot whales are known to take advantage of the grouping effects of human commercial fishing activities as a way to easily catch prey. /=\
Long-Finned Pilot Whale Characteristics
Killed pilot whales in the Faroe Islands Long-finned pilot whales are wide-ranging, medium-sized animals that have a stocky, sturdy body. Males are larger than females. Males reach a weight of 3,800 kilograms (3.8 tonnes, 4.2 US tons, 8,377 pounds) and length of 8.5 meters (28 feet), with an average length of six meters. (20 feet) Females reach a weight of 1,800 kilograms (1.8 tonnes, about 2 US tons, 3,970 pounds) and reach a length of six meters (20 feet), with their average length being 4.8 meters (16 feet). [Source: Julianne Preston, Animal Diversity Web (ADW) /=]
Long-finned pilot whales have a large bulbous or squarish forehead, known as a melon, that varies with age and sex. In some animals, the melon can develop a prominent crease. Long-finned pilot whales have 16 to 26 peg-like teeth in each jaw, which may be an evolutionary adaptation to consuming large amounts of soft squid. Their thick dorsal fin is located about a third of the body length behind the head. As the they mature, their dorsal fin becomes broader and rounder. [Source: NOAA]
This species gets its common name from the pair of long, tapered, sickle-shaped flippers on either side of its body. Long-finned pilot whales are dark black in color, but can sometimes can appear dark gray or brownish. They have pale grayish or whitish marks, such as a diagonal eye-stripe, or a blaze, that extends from behind the eye and up towards the dorsal fin. They also have a large saddle behind the dorsal fin, and an anchor-shaped patch that starts at the throat and extends down their underside.
The most characteristic trait of long-finned pilot whales is their large, bulbous, melon-shaped head. Initially, calves do not have the bulbous head. The melon grows as the calf matures. Like other whales, pilot whales are endothermic (use their metabolism to generate heat and regulate body temperature independent of the temperatures around them) and homoiothermic (warm-blooded, having a constant body temperature, usually higher than the temperature of their surroundings). /=\
Long-Finned Pilot Whale Behavior and Communication
Long-finned pilot whales are diurnal (active during the daytime), nocturnal (active at night), motile (move around as opposed to being stationary), nomadic (move from place to place, generally within a well-defined range), and social (associates with others of its species; forms social groups). In terms of a home range, long-finned pilot whales are nomadic and wander over wide ranges throughout the year. The tend to go where the greatest concentrations of squid can be found. [Source: Julianne Preston, Animal Diversity Web (ADW) /=]
Long-finned pilot whales are highly gregarious animals. They are commonly seen in tight, social pods and sub-groups of 10 to 50 individuals, but have been reported in loose groupings of several hundred or even up to a 1,000 animals. While pods have both male and female members, there are usually a greater number of females, since males have a higher mortality rate and leave their pod when sexually mature in order to mate. Studies have shown that these established pods are maternally based. The strong social structure of these animals has been suggested by mass strandings on beaches. Long-finned pilot whales are known to associate with a variety of other dolphin and whale species, and sometimes even sharks. [Source: NOAA]
At the surface, these whales will often display various active behaviors such raising their heads above the surface (spy-hopping) or lifting their flukes out of the water and splashing them down against the surface (tail-slapping). They are also regularly seen resting or logging at the surface in a chorus-line or stacked formation, and sometimes approach vessels moving at slow speeds. This species has a small, strong, low, bushy blow that is often visible.
Long-finned pilot whales communicate with sound and sense using vision, touch, echolocation (emitting sound waves and sensing their reflections to determine the location of objects) and chemicals usually detected by smell. According to Animal Diversity: The dominant form of communication involves various audible whistles. Whistling remains simple during periods of rest. However, the intricacy of the whistles increases during times of excitement, as well as when the pod is in the process of killing prey. Complex whistles are also heard while the pod is eating and when traveling speeds are high. This indicates that such activities require a greater amount of coordination in the pod. Sounds are also used in echolocation (emitting sound waves and sensing their reflections to determine the location of objects), allowing these whales to orient themselves in space. /=\
Long-Finned Pilot Whale Mating, Reproduction and Offspring
Long-finned pilot whales are viviparous, meaning they give birth to live young that developed in the body of the mother, and engage in year-round breeding. Females mate every three to six years. The breeding season is between the months of April and September in the North Atlantic and between October and April in the Southern Hemisphere. The number of offspring born is one. The average gestation period is 16 months. The weaning age ranges from 23 to 27 months. Females reach sexual maturity between ages six and eight years. Males reach sexual maturity at 12 to 13 years.[Source: Julianne Preston, Animal Diversity Web (ADW) /=]
Long-finned pilot whale are polygynous (males having more than one female as a mate at one time). Mating takes place between, not within, pods. Males display an aggressive courtship behavior, including ramming other males, melon-to-melon, at high speeds.
Calves are pften born on the spring. At birth, they measure about 1.6 and two meters (5 to 6.5 feet) and weigh about 75 kilograms (165 pounds). Young are precocial. This means they are relatively well-developed when born. After 18 to 44 months, the calf stops nursing and is weaned by the cow. Older and/or unreproductive females help care for calves in the social group.
Females are the primary caregivers for calves. Related females usually stay together and form a cohesive pod, whereas mature males travel from one pod to the next. During the pre-fertilization, pre-birth, pre-weaning and pre-independence stages provisioning and protecting are done by females. The post-independence period is characterized by the association of offspring with their mothers. There is an extended period of juvenile learning. /=\
Short-Finned Pilot Whales
Short-finned pilot whales (Scientific name: Globicephala macrorhynchus) are found globally in tropical and temperate oceans. Also known as blackfish, Pacific whales, and potheads, They are one of two species of pilot whale, along with long-finned pilot whales. The two species differ slightly in size, features, coloration, and pattern. In the field and at sea, it is very difficult to tell the difference between the two species. Short-finned pilot whales mature at around 10 years of age. The maximum lifespan is 45 years for males and 60 years for females. [Source: NOAA]
Short-finned pilot whales are long-live, slow to reproduce, and highly social. They live in stable groups of 15 to 30 animals comprised of close family relatives, and tend to live in localized, resident populations, although some populations have wider ranges. Their diet consists primarily of squid, with a small amount of fish. They are commonly found along the coast close to the continental shelf, although some populations have been found to extend into deep, open ocean environments, such as in the eastern tropical Pacific Ocean. Pilot whales are often involved in mass strandings for reasons that are still unclear.
Pilot whales are orcas (killer whales)) can be rivals. They have been reports or orcas harassing pods of short-finned pilot whales and orcas fleeing pilot whale, but generally they tend to stay clear of each other even when pursuing the same food source.
Short-finned pilot whales are hunted in Japan and the Lesser Antilles in the Caribbean. Their blubber has been melted into oil and their bone and teeth have been carved into ornaments and tools. These whale have been heavily hunted in the western Northern Pacific. Hunting is now illegal in many places but still occurs sometimes with government okays. Short-finned pilot whales have no special status according to the Convention on the International Trade in Endangered Species (CITES) and are classified as “Data Deficient” on the International Union for Conservation of Nature (IUCN) Red List. Threats include entanglement, vessel strikes, noise
Short-finned pilot whales prefer warmer tropical and temperate waters and native to the Atlantic, Pacific, and Indian Oceans, with documented populations off the coasts of Japan, Spain, Africa, California, India, and Hawaii. They can be found at varying distances from shore, but typically prefer deeper waters. Areas with a high density of squid are their main foraging habitats. They dive up to depths of 610 meters (2,000 feet).
Short-Finned Pilot Whale Characteristics and Feeding
Adult Short-finned pilot whales weigh between one and three tonnes (1,000 and 3,000 kilograms, 2,200 to 6,600 pounds) and are 3..6 to 7.3 meters (12 to 24 feet) in length. Both sexes are roughly equal in size and look similar. Males are larger. They are known as the “cheetahs of the deep sea” for their deep, high-speed dives to chase and capture large squid. [Source: NOAA, Christine Dombrowski, Animal Diversity Web (ADW) /=]
Short-finned pilot whales are toothed. They have a bulbous melon head with no obvious beak. Their dorsal fin is far forward on its body and has a relatively long base. The body its black or dark brown, with a large gray saddle behind the dorsal fin. There are gray-white markings on the throat and chest that resemble an elongated anchor. They have pointed flippers, which are smaller than those of long-finned pilot whales, which otherwise look similar.
Short-finned pilot whales feed mainly on squid, but they may also feed on octopuses and fish, all from moderately deep water of 300 meters (1,000 feet) or more. They consume about 45 kilograms (100 pounds) of food per day. When they are swimming and probably looking for food, a pilot whale group can spread out over an area nearly a kilometer wide. Around dawn and dusk, they perform deep dives upwards of 600 meters in search of food. It is assumed that these deep foraging dives happen when benthic (bottom-dwelling)-dwelling prey rise and sink in the water column in association with changes in sunlight.
Short-Finned Pilot Whale Behavior
Short-finned pilot whales are natatorial (equipped for swimming), nocturnal (active at night), motile (move around as opposed to being stationary), nomadic (move from place to place, generally within a well-defined range), and social (associates with others of its species; forms social groups). They often stay within a few hundred kilometers and return to squid spawning sites yearly. They will leave an area if food sources have been depleted and will avoid areas that have not had an abundance of food for several years. [Source: Christine Dombrowski, Animal Diversity Web (ADW), NOAA]
Short-finned pilot whales often occur in pods (groups) of 25 to 50 animals. Males have more than one mate — typically a group has one mature male for every eight mature females. Males generally leave their birth school and migrate from pod to pod. Females form kinship pods and remain in them entire lives. Within groups, older non-breeding females can serve as a sort of "storage bank" of information for the pod. During the day, short-finned pilot whales are found resting and traveling, and socialize little. It is assumed that they are more active and social at night when they feed. Short-finned pilot whales travel through a large range in a constant search for food.
Short-finned pilot whales sense using vision, touch, sound and chemicals usually detected with smell and communicate with vision, touch and sound with other whales from their pods. Auditory communication consists of whistles and clicks emitted vocally. Physical communication consists of tail slapping and breaching. Mothers communicate physically by nudging their newborns to the surface. They stay in close physical contact as a means of communication until the newborn is older. Their eyes are specially adapted for life at changing ocean depths. Short-finned pilot whales are sensitive to loud sounds made by humans such as navy sonar and seismic exploration.
Short-Finned Pilot Whale Mating, Reproduction and Offspring
Short-finned pilot whales are viviparous, meaning they give birth to live young that developed in the body of the mother, and engage in year-round breeding, with a peak period between July and August. Mating is not usually observed during the winter months. Calves are born five to eight year apart, with a maximum of four to five calves born to a female in her lifetime. The average gestation period is 15 months. The number of offspring is one. The weaning age is at least two years and the age in which they become independent is three years or more. Females reach sexual maturity at seven to 12 years, with an average of around nine years of age. Males reach sexual maturity at seven to 17 years, averaging 14.6 years. [Source: NOAA, Christine Dombrowski, Animal Diversity Web (ADW) /=]
Short-finned pilot whales are polygynandrous (promiscuous), with both males and females having multiple partners. Breeding occurs between males and females from unrelated pods. Young males disperse shortly after weaning, while young females stay with their mother's pod. Older females do not give birth as often as younger females. The last calf born to a mother may be nursed for as long as 15 years.
Young are precocial. This means they are relatively well-developed when born. Parental care, pre-fertilization and pre-birth protection are provided by females. During the pre-weaning, and pre-independence stages provisioning and protecting are done by females. The post-independence period is characterized by the association of offspring with their parents.
Calves are usually born in the winter during the time squid are spawning. Newborn short-finned pilot whales weigh 140 kilograms on average. Females are the sole caretakers of the calves, and both young and old females make a contribution. Males rarely stay within the same pod after reaching sexual maturity. Females breed until reaching the age of 40, at which they experience menopause. Males can breed until the time of their death, which is normally between 40 and 50 years of age.
Females suckle their calves and teach them to hunt squid. Other females within the same pod will help the mother by watching her young while she is out hunting on her own. Females in the menopausal stage will readily help out the younger, breeding females. Males do not contribute to taking care of young.
Image Source: Wikimedia Commons, NOAA
Text Sources: Animal Diversity Web (ADW) animaldiversity.org; National Oceanic and Atmospheric Administration (NOAA) noaa.gov; Wikipedia, National Geographic, Live Science, BBC, Smithsonian, New York Times, Washington Post, Los Angeles Times, The New Yorker, Reuters, Associated Press, Lonely Planet Guides and various books and other publications.
Last Updated June 2023