The Firecracker Whale
A Compilation of Available Information on
Kogia breviceps
The Pygmy Sperm Whale
by M. Maxwell A. Newman, with assistance from Gary C. Newman
Fairbanks, Alaska - April 15, 1996
Last updated December 20, 2001
Abstract
This paper examines the body of available information on
kogia breviceps
, commonly known as the pygmy sperm whale. Research from strandings of pygmy sperm whales comprise the basic knowledge of this intriguing creature. They are thought to range throughout tropical and temperate waters, but are considered rare. Much smaller than the 15 meter sperm whale and slightly larger than the 3 meter dwarf sperm whale, these three are the only known members of the suborder odonteceti or toothed whales. First identified in 1838 by de Blainville, it has been confused with porpoises and sharks. The pygmy sperm whale also exhibits certain behavior unknown in other whales for which it had been given the nickname the "firecracker" whale.
Strandings and sightings are being reported more frequently, but perhaps only due to an increased awareness of cetaceans in general and improved abilities to identify them in their natural habitat. There is also evidence of environmental debris that is causing more pygmy sperm whales and other marine species damage.
Despite efforts to help sick or injured pygmy sperm whales back to health, nearly all have not survived in captivity. The 1981 record remained at 25 days until 1994 when, after six months, a healthy juvenile pygmy sperm whales was released off the coast of Florida. There has been no effort to keep pygmy sperm whales in captivity - the goal has always been to release the animal once it was healthy enough to cope in its natural environment.
Table of Contents
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Introduction
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Physical Characteristics
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Location and Migration
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Diet
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Behavior
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Mating and Reproduction
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Summary
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Bibliography
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Updated Links
Kogia breviceps
(or pygmy sperm whale)
is one of the three known odontocete whales or toothed whales. The other two odontocete whales are the larger sperm whales and the slightly smaller dwarf sperm whales. See table 1 and figure 1. It has been confused with being a porpoise, much like the dwarf sperm whale, which is called a rat porpoise in the Lesser Antilles in the Caribbean Ocean. It has markings of a pseudo-gill that has also led to its being thought of as a shark.
First discovered and identified as a separate species by de Blainville off the Cape of Good Hope (Australia) in 1838, there remained some controversy for some time over the classification of the pygmy sperm whale. The American Naturalist of 1871 had an article describing the current state of classification of
kogia breviceps
, including the controversy over the name '
kogia'
not being suitable for the classical Latin naming system developed by Linnaeus. It was called 'barbarous and undefined' and others favored the more Latin sounding name '
euphysetes'
(meaning good or easy blower), yet the name '
kogia'
has remained. It was humorously suggested in this article that the name
euphysetes
may be applied to those so concerned about the name.
Adult pygmy sperm whales range from 2.7 - 3.4 meters in length. They have three stomachs and can weigh 318-408 kilograms. They have spherical type heads with an underslung lower jaw containing 10-16 pairs of long, curved, sharp teeth in each. The upper jaw has no teeth. They have a stocky body and a blowhole that is asymmetrical and leans to the left. The dorsal (or top) side of these whales is a dark brown-black which shades gradually to a grayish-white on the belly's ventral flanks. Behind each eye is a dark patch resembling a fish gill the height of the head region. The tiny falcate dorsal fin is located to the rear of the midback. Unlike the giant sperm whale (
physeter catadon
or
physeter macrocephalus
), the pygmy sperm whale dorsal fin is well-defined.
While having two nostrils, the left is substantially larger than the right. This led M. Carvin to conclude that the left nostril is primarily associated with breathing functions and the right, along with surrounding soft tissues, was intended for sound production of clicking. He speculated that kogia has become so anatomically specialized in efficient click production that the whale has lost the ability to produce whistles.
The pygmy sperm whale, like the other sperm whales, have a melon shaped area above the skull that acts to produce the sounds for echolocation. Although the pygmy sperm whale has ears, the earholes are plugged with wax. This whale actually "hears" by detecting vibrations on a very thin section of bone on the lower jaw, which is then transmitted to the earbone. The melon acts to focus and transmit sounds the whale creates for its various purposes.
The kogia species can be found in all temperate and tropical waters throughout the world. Observations and strandings are noted on the Atlantic, Gulf and Pacific Coasts of the United States, Australia, eastern and southern Africa, the Philippines, Japan, India, Europe, South America. It is not known how far it may or may not migrate. It is considered as a deep water whale.
The pygmy sperm whale is known to eat mostly octopus and squid, but will also eat crabs, small fish, and other invertebrates such as jellyfish. The National Aquarium in Baltimore reported adult pygmy sperm whales can eat 25-30 lb. daily. Their relatives, the dwarf sperm whale, have been shown to descend to depths of 300 meters to obtain fish. The pygmy sperm whales method of hunting is unknown in the wild, but recent experiences with Inky (see below) may offer some clues. In addition, K. Beckman stated that
kogia
uses its sonar abilities to stun or debilitate it's favorite food - squid.
Our knowledge of pygmy sperm whales behavior in the wild is limited due to the fact that it is not a coastal animal and prefers to inhabit the deeper sections of the oceans. They are known to travel individually or in groups of 2-3.
There are similarities to other cetacea, such as using echolocation as documented by Michael John Carvan III, but there seem to be more differences. When diving, they do not roll forward at the surface as do most other whales. Rising slowly to the surface to breath, they breach and blow inconspicuously. They have been observed with their tail hanging low in the water beneath them. Recent experience with 'Inky' (see below) has added a new dimension of understanding this amazing creature.
The most unique behavior of the pygmy sperm whales is they use a system of ejecting a red-ish brown fluid from their colon, called 'inking'. They do this when excited, scared, or foraging. Porpoising, breaching, and speed swimming and other high energy behaviors related to inking, have been described by those who have maintained pygmy sperm whales in a rehabilitation setting. The Japanese fisherman have called the pygmy sperm whale 'tsunabi', the rocketing firework. A more passive precursor to inking has also been noticed as the whale rests motionless on the surface of the water, a behavior the Japanese name Uik-Kujira or floating whale. The whale would then nearly somersault underwater while inking. Observed by the National Aquarium, the pygmy sperm whales named Inky was found to use inking to camouflage and confuse squid, then located the squid by sonar through the ink and ate them.
The second unknown behavior of the pygmy sperm whales was a process of regurgitation. One of the primary sources of food for the pygmy sperm whales is squid, which have an inedible beak and pens. Recent observation has offered the opinion that they regurgitate from the first or second stomach to void these and other inedible objects.
Unfortunately, pygmy sperm whales don't seem to be able to distinguish between plastic bags, mylar balloons and another of their favorite foods - jellyfish. This was the cause of the New Jersey stranding of a juvenile female pygmy sperm whale on Thanksgiving Day 1993. She was evacuated to the National Aquarium in Baltimore. After two months of poor eating and constant regurgitation, an endoscopy was performed which discovered numerous plastic items in the stomachs, along with a high concentration of compacted quid pens and peaks. Once cleared of this debris, the animal began gaining weight. From necropsies of pygmy sperm whales performed, it was estimated that the females would regurgitate every 2.1-2.5 days, but male a more frequent 1.2-1.6 days.
The pygmy sperm whale and its relative dwarf sperm whale are the second most commonly stranded cetacean in the south eastern U.S., next to the bottlenosed dolphin. The thesis of Victoria Credle explored the influence of environmental magnetic phenomenon may have on the magneto-receptive abilities of kogia based upon 384 stranding from N. Carolina to Texas. She found a correlation with areas that normally had high coastal magnetic fields and experienced sharp changes in magnetic field as well as during periods of low magnetic activities.
Not much is known about pygmy sperm whales reproduction and mating. It is known that mothers have one calf with a gestation of 11 months. One source suggests that calves are typically born in the late spring. Young are about 47 inches at birth. Males are sexually mature at 2.7 to 3 meters, females at 2.6-2.7 meters. A more detailed study that details the normal female reproductive anatomy by Kimberlee Beckman in her masters thesis has helped to further that cause, but still much remains to be learned.
In conclusion, the information that I found was extremely unexpected, as there was much more available than I had thought possible. However, there is obviously still a great amount to learn. It is ironic that our body of knowledge is lacking because we haven't had the exposure to this species as we have other whales that have been hunted commercially.
The high number of pygmy sperm whale strandings continues to be of concern and further study is warranted. This shy whale is not currently endangered, but is certainly being harmed from environmental solid waste. It exhibits very special and interesting characteristics. I hope this information is as interesting for you to read about as it was for me to find it.
-
Beckmen, Kimberlee B.
,
Gross and Microscopic Anatomy of the Female Reproductive Tracts of the Dwarf and Pygmy Sperm Whales
, Master's Thesis, University of Miami, May 1986.
-
ibid, personal conversations, March 1996.
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Carvan III, Michael John,
The Descriptive Anatomy of Sound Production and Propagation Tissues in
Kogia spp
. Using Magnetic Resonance and Computer Tomography Imaging
, Masters Thesis, University of Miami, August 1988.
-
Credle, Victoria R.,
Magnetite and Magnetoreception in Stranded Dwarf and Pygmy Sperm Whales
, Master's Thesis, University of Miami, August 1988.
-
Elsberry, Wesley R.
Protected Marine Species Resources: Listing by Species
, Internet source, March 1996.
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Ettlin, David Michael, "Whale's Stomach Tells Tale of Pollution", The Sun (newspaper), Baltimore, January 7, 1994.
-
ibid., "Rescued pygmy sperm whale 'Inky' is well again and soon will swim free", The Sun (newspaper), Baltimore, May 1994.
-
ibid., "A leap and a dive - and Inky's on her own", The Sun (newspaper), Baltimore, June 8, 1994.
-
Gill, Theodore,
American Naturalist
, "The Sperm Whales, Giant and Pygmy, April 1871.
-
Gunter, Gordon, Hubbs, Carl L., Beal, M. Allan,
Records Of
kogia breviceps
From Texas Remarks On Movements And Distribution
, Journal of Mammology, May 1955.
-
Kummerer, Robert,
letter to newsgroup
, Internet source, Jan 26, 1996.
-
Kummerer, Robert
, personal Email communications, March 1996.
-
McGowan, Tom,
Album of Whales
, Rand McNally & Co., 1980.
-
Missehara, Lou, "A whale of a happy ending", article in Florida Today (periodical), June 1994.
-
National Aquarium in Baltimore,
Pygmy Sperm Whale Fact Sheet
, National Aquarium, 1995.
-
Palm Beach Post Wire Services, "Inky the whale disappears off Georgia" (newspaper), June 1994.
-
Pitt, Valerie, Hoke, Helen,
Whales
, Franklin Watts, 1973.
-
Roest, Aryan I, Thurmond, William, Montgomery, David H.,
Pygmy Sperm Whales in Georgia
, Journal of Mammology, May 1955.
-
Schofield,T. David,
Observations on Inking and Regurgitation in a Juvenile Female Pygmy Sperm Whale,
Kogia breviceps
, National Aquarium in Baltimore, draft paper March 1996.
-
Sylvestre, J.P.,
Review of Kogia Specimens Kept Alive in Captivity
, Investigation on Cetacea, Vol 15 : 201-219. 1983.
-
author unidentified,
Dwarf Sperm Whales, from the Lesser Antillean Island of St. Vincent
, Journal of Mammology, May 1973.
-
source unidentified,
Pygmy Sperm Whale
, page 88, provided by Karin Cooper, Fairbanks, Alaska, 1996.
Since this original paper was done, we've had very little information to add.
-
Carol McGee
sent us
this link
about a baby pygmy found on the Summer Solstice 2000 off the Florida Keys and now named "Summer".
For further information, email
Max Newman
Thank you for visiting this page.
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