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Conservation Status:  Least concern-protected

Climate Change:  Uncertain

AquaticPygmy Sperm Whale

Kogia breviceps MammalsMarine

Aquarium of the Pacific - Online Learning Center - Species Print Sheet

Pygmy Sperm Whale
A drawing of a pygmy sperm whale showing the countershading | Coirtesy of NOAA's National Marine Disheries
Pygmy Sperm Whale
A drawing of a pygmy sperm whale showing the countershading | Coirtesy of NOAA's National Marine Disheries

Species Overview

When a whale dies and the carcass sinks to the deep ocean floor, it becomes a “whale fall”, a temporary ecosystem for a diverse community of marine life as is shown in our exhibit featuring a model of a pygmy sperm whale carcass.

This toothled whale is one of three members of the superfamily Physeteridae—sperm whales, pygmy sperm whales, and dwarf sperm whale. It was not until 2005 that genetic testing demonstrated that pygmy and dwarf sperm whales were two, not one species as previously thought and that they belonged in a separate family from the “giant” sperm whale, the family Kogiidae. Like sperm whales, their mouth is on the underside of their body, but unlike sperm whales they have very few and very small teeth that are sharply pointed and curved. Like sperm whales, they are suction feeders with a preference for squid.

Species In-Depth | Print full entry

At the Aquarium

The pygmy whale is not currently on exhibit. This information is supplied for use as a reference.

Geographic Distribution

Tropical, subtropical, and temperate seas waters of the world ocean as far north as the northern tip of Scandinavia and as far south as Cape Horn at the tip of South America.

Habitat

Pygmy sperm whales are rarely seen in the wild and not much is known about them. however, what is available indicates that they prefer deep, off-shore waters at depths of 400 to 1000 m (1,300 to 3,300 ft) near continental shelves where cold water upwelling brings a plentiful supply of food.

Physical Characteristics

There is very little information available about this species as it is rarely seen in the wild. Most of what is known has been derived from necropsies of beach stranded animals that did not survive. Most of these strandings have been females with newborn calves or females who had recently given birth.

Pygmy sperm w hales have a dolphin-shaped body with a short, broad, asymmetrical head, (often referred to as “shark-like”). In adults the head takes up roughly 15 percent of the total body length. The spermaceti organ inside the head, together with the melon on the left side of the head is used to focus sound. The pectoral fins are set low on the body and close to the head. The dorsal fin, located behind the midsection, is very small and falcate (curved and pointed. There is a light colored, curved mark behind each eye which resembles a gill and which is called as the “false gill”. The flippers are located behind and below the “false gill”. They are large and slightly rounded at the tips. The fluke is almost dolphin-like with a deep notch in the center.

The single large blowhole is on the front of the head pointing forward. The mouth is under the underside of the ehad and the lower jaw is narrow and short with 12 to16 slender, sharp, fang-like teeth that fit into holes in the upper jaw. The large square upper jaw projects above the narrow lower jaw.

These whales are counter-shaded, dark steel-gray or dark brown-gray on the dorsal surface and light gray or cream to pink on the ventral side.

Size

Adult males and females appear to be close in size. Lengths and weights are recorded from beached specimens. Length: 2.7-3.8 m (8.8 to 14 ft) Weight: 315 to 544 kg (700 to 1000 lb)

Diet and Feeding

Suction feeders, these whales prefer squid; however, examination of the stomach contents of beached pygmy sperm whales reveal that they also fish, octopus, crabs, shrimp including mantis shrimp.

Reproduction

This species is thought to become mature at about four to five years of age. It is also believed that mating and breeding take place seasonally between early spring and late fall. Calves are born after a 19-11 months gestation. Newborns are average 120 cm (almost 4 ft) in length and weigh about 54 kg (120 lb). They nurse for about a year. Some beached mothers have been found to be pregnant and nursing at the same time, indicating they can mate and produce a calf every year.

Behavior

Pygmy sperm whales are normally found alone or in pairs, occasionally in small pods. They are deliberate in their movements, rising to the ocean surface slowly, carefully, splashing very little as they make low, inconspicuous blows and hanging motionless in the water for a while. Their dives are equally inconspicuous. They simply drop out of sight. They have rarely been seen breaching. Studies have shown the only sound they make is “clicks” in the ultrasonic range.

Adaptation

Their short, narrow lower jaw is a clue to the type of feeding these whales engage in. They suction their prey off of or near the ocean floor. When frightened or disturbed these little whales use a surprising defense tactic. They have a specialized sack in their intestines that contains a dark reddish-brown liquid. They can expel this liquid to create cloud in the water that obscures them, much like squid releasing ink.

Longevity

The life span of these whales is believed to be about 17 years.

Conservation

There is so little information known about this species that it is listed as Lower Risk least concern in the IUCN Red List. It is protected under the US Marine Mammal Protection Act and CITES Appendix II (Convention on International Trade in Endangered Species of Wild Fauna and Flora.

Pygmy sperm whales are incidentally taken as bycatch in fishing gear including driftnets, gillnets and purse seine operations. This species has been recently taken in commercial harpoon fisheries in Indonesia, the Lesser Antilles, and Japan. Due to their behavior of “resting” motionless” on the surface of the ocean, they are occasionally subject to ship strikes. Some stranded whales have been documented with plastics and other garbage blocking their guts. Stranded specimens have also been documented with degenerative heart disease, immune system problems and heavy parasite infestations. This species of whale may be sensitive to underwater sounds and anthropogenic noise.

Amazing Facts

There is very little information available about this species as it is rarely seen in the wild. Most of what is known has been derived from necropsies of beach stranded animals that did not survive. Most of these strandings have been females with newborn calves or females who had recently given birth.

The name “Kogia” may have come from the word “codger”, which is a Latinized English word meaning an elderly, eccentric man, or from the name of a Turkish man who observed whales in the wild, Cogia Effendi. “Brevis” is Latin for short, and “cepitis” is a form of Latin for head.

A mother pygmy sperm whale and her calf beached in Florida Sound, March 3, 2013. Pygmy sperm whales are the second most common stranded species in this localation.