Physeter macrocephalus

Physeter catodon, the sperm whale, is the largest toothed predator on Earth. Males can be over 18m long, weighing up to 50,000kg.Mature female sperm whales tend to live in social groups of up to 15 mature females and their offspring, whereas mature males live alone or in smaller groups.The sperm whale is listed as vunerable to extinction by the IUCN. Commercial whaling was the biggest threat to this species.

The sperm whale is the largest of the toothed whales, with males growing up to 20 metres in length. It also has the largest brain of any living animal, and it was a sperm whale that was pitted against Captain Ahab in Herman Melville's classic novel, Moby Dick (2). Sperm whales have huge square heads, comprising almost a third of the total body length (2) (3); indeed the specific name macrocephalus means large head. Uniquely among cetaceans, the single blowhole is located on the left of the head rather than on the top (3) and so these whales are easily identified at a distance by their low, bushy spout, which is projected forward and slightly to the left (2). Further down the body toward the tail there is usually a large hump on the back, followed by a series of smaller bumps (3). The dark brown to bluish-black skin, which is splotched and scratched, is said to have a texture like that of a plum stone (2) (3). Males tend to be somewhat larger and heavier than females (3), and have larger heads in relation to their body size (6). The huge heads of sperm whales contain a large cavity, the spermaceti organ, filled with a waxy liquid called spermaceti oil. This wax can be cooled or heated, possibly by water sucked in through the blowhole, and thus shrinks and increases in density (helping the whale sink), or expands and decreases in density (helping the whale rise to the surface) (5). Whalers likened the substance to semen, and this is the origin of the common name of the species (6).

Sperm whales are found throughout the world's oceans in deep waters to the edge of the ice at both poles (Waring et al. 2009 and references therein).

According to Waring et al. (2009), results of multi-disciplinary research conducted in the Gulf of Mexico during the first decade of the 21st Century confirm speculation that Gulf of Mexico Sperm Whales constitute a stock that is distinct from other Atlantic Ocean stocks(s). Sperm whales were commercially hunted in the Gulf of Mexico by American whalers from sailing vessels until the early 1900s. In the northern Gulf of Mexico (i.e., U.S. Gulf of Mexico), systematic aerial and ship surveys indicate that sperm whales inhabit continental slope and oceanic waters, where they are widely distributed. Seasonal aerial surveys confirm that sperm whales are present in at least the northern Gulf of Mexico in all seasons. The best available estimates indicate a population of around 1,500 Sperm Whales in the northern Gulf of Mexico. (Waring et al. 2009 and references therein)

Antarctica, Azores, Azores Exclusive Economic Zone, Belgian Exclusive Economic Zone, Doel, European waters (ERMS scope), Greek Exclusive Economic Zone, Gulf of Mexico, Gulf of St. Lawrence, Knokke, Koksijde, Mediterranean Sea, New Zealand Exclusive Economic Zone, North West Atlantic, Pacific Ocean, Seychelles, St. Lawrence Estuary, Subantarctic Waters, World Oceans

Sperm whales roam the deep waters of all the oceans, though they seldom approach polar ice fields and are most common in temperate and tropical latitudes. They have also be seen occasionally near coastlines in the Gulf of Mexico, where they were once quite common.

Biogeographic Regions: arctic ocean (Native ); indian ocean (Native ); atlantic ocean (Native ); pacific ocean (Native )

in all oceans; Antarctica/Southern Ocean; East Pacific; Eastern Atlantic Ocean; Indo-West Pacific; Western Atlantic Ocean.

occurs (regularly, as a native taxon) in multiple nations

Canada

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

United States

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

Global Range: (>2,500,000 square km (greater than 1,000,000 square miles)) Throughout the world's oceans; adult females and young generally stay between 40 degrees north and 40 degrees south latitude. Nonbreeding males range into high latitude waters. Northern and southern hemisphere populations apparently are reproductively isolated from each other. See IUCN (1991) for further details.

Equatorial to polar in all world's oceans.

Sperm whales are found in all of the oceans of the world, except the high Arctic (6).

Above weights are given for mature male giant sperm whales. Females only weigh about 1/3 as much as males. Males may reach 19 m while females are only 12 meters. Newborn calves measure about 4 m and are about 1/25 the weight of females.

The enormous (up to 1/3 of total body length), box-like head of Physeter catodon sets it apart from all other species. The head contains a spermaceti organ whose function is not entirely known. It may serve to focus and reflect sound or may be a cooling organ to diminish the whale's volume and its buoyancy during prolonged dives. The giant sperm whale has the largest of mammalian brains in terms of sheer mass (approximately 9 kg). The blowhole slit is S-shaped and positioned on the left side of the head. There are 18-28 functional teeth on each side of the lower jaws, but the upper teeth are few, weak and nonfunctional. The lower teeth fit into sockets in the upper jaw. The gullet of Physeter catodon is the largest among cetaceans; it is in fact the only gullet large enough to swallow a human.

The dorsal fin is replaced by a hump and by a series of longitudinal ridges on the posterior part of the back, and the pectoral fins are quite small, approximately 200 cm. long. Tail flukes are 400-450 cm. The blubber layer of the giant sperm whale is quite thick, up to 35 cm. With respect to coloration, males often become paler and sometimes piebald with age. Both sexes have white in the genital and anal regions and on the lower jaws.

Range mass: 35000 to 50000 kg.

Other Physical Features: endothermic ; homoiothermic; bilateral symmetry

Sexual Dimorphism: male larger

Length: 1830 cm

Weight: 4.8E7 grams

Length: Females 11-12 m. Males 15-18 m.

The enormous (up to 1/3 of total body length), box-like head of the sperm whale sets it apart from all other species.The blowhole slit is S-shaped and positioned forward on the left side of the head. There are 18-28 functional teeth on each side of the lower jaws, but the upper teeth are few, weak and nonfunctional. The lower teeth fit into sockets in the upper jaw. The gullet of is the largest among cetaceans; it is in fact the only gullet large enough to accomodate a human. The dorsal fin is replaced by a hump and a series of longitudinal ridges on the posterior part of the back. The flippers are quite small, approximately 200 cm. long. Tail flukes are 400-450 cm in width. The blubber layer of the sperm whale is quite thick, up to 35 cm. With respect to coloration, males often become paler and sometimes piebald with age. Both sexes have white in the genital and anal regions and on the lower jaws.

Sperm whales swim through deep waters to depths of 2 miles, apparently limited in depth only by the time it takes to swim down and back to the surface. Their distributions are depend upon season and sexual/social status, however they are most likely to be found in waters inhabited by squid- at least 1,000 m deep and with cold-water upswellings. Because they are so well-adapted for deep water swimming, they are in real danger of stranding when they move inshore.

Aquatic Biomes: benthic

oceanic

Depth range based on 3165 specimens in 1 taxon.
Water temperature and chemistry ranges based on 2973 samples.

Environmental ranges
  Depth range (m): 0 - 0
  Temperature range (°C): -0.849 - 29.546
  Nitrate (umol/L): 0.008 - 26.054
  Salinity (PPS): 30.381 - 37.431
  Oxygen (ml/l): 4.467 - 8.078
  Phosphate (umol/l): 0.036 - 1.743
  Silicate (umol/l): 0.464 - 37.572

Graphical representation

Temperature range (°C): -0.849 - 29.546

Nitrate (umol/L): 0.008 - 26.054

Salinity (PPS): 30.381 - 37.431

Oxygen (ml/l): 4.467 - 8.078

Phosphate (umol/l): 0.036 - 1.743

Silicate (umol/l): 0.464 - 37.572
 
Note: this information has not been validated. Check this *note*. Your feedback is most welcome.

Habitat Type: Marine

Comments: Pelagic, prefers deep water, sometimes around islands or in shallow shelf waters (e.g., 40-70 m; Scott and Sadove 1997). Tend to occur in highest densities near productive waters, and often near steep drop-offs or strong oceanographic features, e.g. edges of continental shelves, large islands, and offshore banks and over submarine trenches and canyons (Gosho et al. 1984, Reeves and Whitehead 1997, Gregr and Trites 2001, Whitehead 2003). Females generally restricted to waters with surface temperatures warmer than about 15 degrees C and rarely found in waters less than 1000 m deep. Males, although primarily found in deep water, are sometimes found in waters 200 to 1000 m deep (Reeves and Whitehead 1997).

Deep marine waters, warm and cold.

Inhabits the open ocean in offshore areas, although providing that water is deeper than 200 metres they may occasionally be seen closer to land (2). They occur in tropical to sub-polar waters (2).

Non-Migrant: No. All populations of this species make significant seasonal migrations.

Locally Migrant: No. No populations of this species make local extended movements (generally less than 200 km) at particular times of the year (e.g., to breeding or wintering grounds, to hibernation sites).

Locally Migrant: Yes. At least some populations of this species make annual migrations of over 200 km.

Seasonal north-south migration; at higher latitudes in summer than in winter. Males move north in the summer to feed. In fall, both sexes migrate toward the equator. In winter, typically distributed south of 40 degrees N. Females, calves, and young remain in tropical or temperate waters while older males migrate to higher latitudes in summer. Males sometimes occur as far north as the Bering Sea.

Physeter catodon feeds mainly on squid (especially giant squid), octopus and deepwater fishes, but it also take sharks and skates. It consumes approximately 3 per cent of its body weight in squid per day.

Animal Foods: fish; mollusks

Primary Diet: carnivore (Molluscivore )

Comments: Eats primarily medium to large squids, sometimes also octopus and various fishes. Large males at high latitudes also take large quantities of demersal and mesopelagic sharks, skates and fishes (Gosho et al. 1984, Jefferson et al.1993, Perry et al. 1999, Whitehead 2003). Dives deeply when foraging, some dives over 1800 m have been recorded, but most are less than 500 m (Potter and Birchler, in Wilson and Ruff 1999). Apparently feeds throughout the year. Although species population depleted by whaling, may take about 75 million metric tons of food from the ocean each year; an amount similar to that taken by all human marine fisheries (Whitehead 2003).

Large squid, octopuses, demersal fish, rays, sharks, sometimes crustaceans.

Physeter catodon (sperm whale) is prey of:
Homo sapiens

Based on studies in:
Antarctic (Marine)

This list may not be complete but is based on published studies.

Physeter catodon (sperm whale) preys on:
Cephalopoda

Based on studies in:
Antarctic (Marine)

This list may not be complete but is based on published studies.

10,000 to >1,000,000 individuals

Comments: World population in the mid-1980s was estimated at 982,200 (410,700 in the southern ocean, 100,000 in Atlantic, 275,000 in eastern Pacific, 198,000 in western Pacific. Other estimates range from 700,000 to 2 million (Matthews and Moseley 1990). More recently, Whitehead (2003) estimated global population of very approximately 360,000 whales based on extrapolation from visual surveys. None of these estimates should be regarded as particularly precise (see IUCN 1991).

Basic social unit is mixed school of adult females plus their calves and juveniles (usually about 20-40 individuals). As males grow older they leave this group and form bachelor schools (of variable sizes up to about 50 individuals). The largest males tend to be solitary (but see Christal and Whitehead 1997). Likely the world's deepest diving mammal (documented at 2,500 m.).

Comments: Active day/night.

Average lifespan
Status: wild: 77.0 years.

Maximum longevity: 77 years (wild) Observations: This whale has the biggest brain among mammals weighting about 9.2 Kg (Ronald Nowak 1999).

These whales have a polygamous mating system. During the breeding season, breeding schools composed of 1-5 large males and a mixed group of females and males of various ages form. At this point, there is intense competition among the males for females (including physical competition resulting in battle scars all over the heads of males). Only about 10-25% of fully adult males in a population are able to breed.

Mating System: polygynous

Females mature sexually at 8-11 years, and males mature at approximately 10 years, although males do not mate until 25-27 years old because they do not have a high enough social status in a breeding school until that point. Maximum known life span is 77 years. Gestation period is 14-16 months and a single calf is born, which nurses for up to 2 years. The reproductive cycle occurs in females every 2-5 years. The peak of the mating season is in the spring in both Northern and Southern hemispheres so that most calves are born in the fall.

Breeding interval: The reproductive cycle occurs in females every 2-5 years

Breeding season: The peak of the mating season is in the spring in both Northern and Southern hemispheres

Average number of offspring: 1.

Range gestation period: 14 to 16 months.

Range weaning age: 24 (high) months.

Average weaning age: 24 months.

Range age at sexual or reproductive maturity (female): 8 to 11 years.

Average age at sexual or reproductive maturity (male): 10 years.

Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); viviparous

Average birth mass: 1e+06 g.

Average number of offspring: 1.

Average age at sexual or reproductive maturity (male)
Sex: male: 3650 days.

Gestation lasts 14-15 months. Births occur May-September in Northern Hemisphere, November-March in Southern Hemisphere. Single young is produced every 3-6 years. Young are weaned in about 1.5-3.5 years, though young may continue to nurse for several years. Females sexually mature at 7-11 years; pregnancy rate gradually declines after age 14. Males may not breed until about 25 years old. May up to at least 60-70 years.

Mating season takes place from late winter to early summer. Gestation period is approximately 14-15 months, young are 3.5-4.5 m long at birth. Calves nurse for up to 2 years.

Sperm whales were once quite abundant in the Gulf of Mexico, but due to commercial whaling operations, they are seldom seen in this area anymore. Worldwide however, sperm whales populations are more stable than that of many other whales, although they continue to be listed as endangered by USDI (1980). The sperm whale is now the most abundant of the great whales, having been hunted with less intensity that the baleen whales. Worldwide, sperm whales number about 1,500,000.

IUCN Red List of Threatened Species: vulnerable

Accidental?

Canada

Rounded National Status Rank: N3 - Vulnerable

United States

Rounded National Status Rank: NU - Unrankable

Rounded Global Status Rank: G3 - Vulnerable

Reasons: Occurs widely in all oceans; protected by international and national regulations; total population is large (several hundred thousand) but trend is difficult to determine; threatened by general deterioration of marine ecosystem.

The Sperm Whale is listed as an endangered species under the ESA. IWC regulations have halted the commercial take of this species. Listed in CITES Appendices I and (for some countries) II. There is some concern over the number of Sperm Whales entangled in fishing gear.

Classified as Vulnerable (VU) on the IUCN Red List 2007 (1) and listed under Appendix I of CITES (4).

Global Short Term Trend: Unknown

Degree of Threat: B : Moderately threatened throughout its range, communities provide natural resources that when exploited alter the composition and structure of the community over the long-term, but are apparently recoverable

Comments: Historically hunted for spermaceti, ambergris, and oil. No longer threatened by direct catching, but entanglement in fishing gear may cause mortality in some areas. Potentially threatened by ocean pollution and ingestion of plastics. Since the introduction of fast ferries into the Canary Islands in 1999, significant increases in collisions fatal to whales, mainly sperm whales, have been observed (Tregenza et al. 2004).

Sperm whales have a long history of commercial exploitation (1). Large-scale hunting began in 1712 in the North Atlantic, based at Nantucket in America (4). They were not widely hunted for their meat, but for ambergris and spermaceti. Ambergris is a substance that collects around the indigestible beaks of squid in the stomach of the whale, and was highly prized for use as a fixative in the perfume industry. Although artificial alternatives are now available, some perfume makers prefer to use ambergris today. Spermatceti was used in the production of cosmetics and candles (7). Sperm whales still have an economic value today for meat in Japan. Since the 1980s, the International Whaling Commission brought an international moratorium on whaling into force. Despite this measure, Japan continues to hunt sperm whales, and relatively small numbers are taken each year with hand harpoons at Lamalera, Indonesia (1). Further threats include entanglement in fishing gear and collisions with boats (1). Although whaling has, with the exceptions outlined above, largely ceased, the after-effects of such prolonged and intensive hunting are still being felt today. It is thought that the selective hunting of the largest, breeding males will have decreased pregnancy rates, and the loss of the largest females from nursery groups would have decreased the survival of the groups (1).

Biological Research Needs: Studies needed that combine immunology, toxicology and demography and that involve populations occurring over a gradient of environments, to assess the effects of chemical pollution (Reeves and Reijnders 2002).

Needs: Enforce international and national protection measures. Prevent habitat degradation caused by dumping of toxic wastes, sewage, and garbage.

As a species, the sperm whale is not facing immediate threat, but some populations need to be carefully monitored, and there is need for tight management of any exploitation (1). In the eastern tropical Pacific, recent whaling was extremely intensive, and birth rates at present are very low. The Mediterranean population is particularly susceptible to collisions with ships and entanglement with fishing gear (1).

Being fiercly aggressive, bull giant sperm whales posed a threat to small-boat whalers in the 19th century. Sperm whales are no match for modern whaling equipment, however. They have also been known to become entangled in trans-Atlantic telephone in dives 3/4 mile deep, but this type of incident is rare.

The head of the sperm whale contains 3-4 tons of spermaceti, a substance valued as a lubricant for fine machinery and a component of automatic transmission fluid. It is also used in making ointments and fine, smokeless candles (once it solidifies into a white wax upon exposure to air). Physeter catodon has also been a target of commercial whaling in years gone by, notably in areas around the Gulf of Mexico. The meat of the whale is not generally consumed. Instead, spermaceti is extracted from the head, and the teeth are often used as a medium for the artistic form of engraving and carving known as scrimshaw. The most important product obtained from giant sperm whales is the oil once used as fuel for lamps and now used as a lubricant and as the base for skin creams and cosmetics. A gummy substance called ambergris forms in the large intestines of sperm whales and can be found floating on the surface of the water or washed ashore once it is expelled. It was once believed to have medicinal qualities, but it is now used in connection with manufacture of perfumes, based on the fact that when it is exposed to air, it hardens and acquires a sweet, earthy smell. The island Ambergris Cay, just south of the Gulf of Mexico, was given its name because of the great quantities of this substance gathered along its shores.

Comments: Source of ambergris (formed in digestive system), which has been used as fixative in perfume industry. Formerly (prior to ban on whaling) a very important commercial species (source of oil, spermaceti, and meal), with annual harvests peaking in the 1960s at 29,000. See IUCN (1991) for information on historical exploitation.

Vulnerable (VU)