Melon-headed whales are small members of the dolphin group. They can reach a length of 9 feet (2.7 m) and weight of 460 pounds (210 kg).
They have a small head with a rounded melon and no discernable beak. Their dorsal fin is relatively large and they have pointed, tapering flippers (pectoral fins). Body color is dark with a large dorsal cape and dark areas on the side of the face that are not always readily apparent.
Females have gestation periods of approximately 12 months. Lactation period and many other reproductive facts are poorly known. Longevity is 22 years for males and 30 years for females.
Melon-headed whales often occur in groups of hundreds to over 1,000 animals. Smaller, coordinated subgroups are common within the larger groups. They are often found on the edge of, or behind, schools of Fraser’s dolphins.
They feed primarily on squids, fishes, and some crustaceans in moderately deep water.
|460 pounds (210 kg)|
|9 feet (2.7 m)|
|dark gray with a small head and no discernable beak|
|22 years for males;
30 years for females
|squids, fishes, and some crustaceans|
|often occur in groups of hundreds to over 1,000 animals|
RELATIVE SPECIES: False killer whale, Pygmy Killer Whale
NEIGHBORING SPECIES: Fraser’s dolphin, False Killer Whale, Pygmy Killer Whale
THREATS: Caught in fishing gear, used to be harpooned for its teeth which were sold as “porpoise tooth” necklaces to be used for currency in the Solomon Islands. Rarely hunted in Japan, because their meat is not palatable.
DIET: Pelagic fish, squid and crustaceans.
MANNER OF FEEDING: Feed on prey that inhabit depths of 5,000 Ft
BEHAVIOR: Travel in groups of several hundred. Very gregarious. Likes to make a large splash and to push water forward as they swim. Sometimes they follow boats and play in the wakes. Large mass strandings are common, suggesting that they have tight social bonds. Often seen with pods of Fraser’s dolphins.
REPRODUCTION: Gestation last 12 months.
LIFE SPAN: 20-33 years
They prefer deeper areas of warmer tropical waters where their prey are concentrated.
Melon-headed whales are found primarily in deep waters throughout tropical areas of the world.
The most recent stock assessment reports with population estimates are available on our website.
- Bycatch occurs in some areas, mostly Japan and areas in the Pacific, though not to any large extent
- no recent bycatch records from the U.S.
- sonar and underwater noise
- Mass stranding is fairly common in this species
- A stranding event in 2004, in which 150-200 melon-headed whales in Hawaii remained inside a bay on the island of Kauai until herded out by volunteers, may have been related to nearby U.S. Navy training involving the use of sonar.
There are no known conservation efforts directed specifically at this species as they are poorly known and have few fishery interactions or other known threats.
This species is protected under the Marine Mammal Protection Act of 1972 as amended.
- Melon-headed whales have more teeth than the other blackfish (pilot, pygmy killer, and false killer whales) with 20 to 26 pairs of teeth in each jaw as opposed to less than 15 pairs for the other blackfish.
- Melon-headed whales make fast, low leaps from the water as they swim.
- Mass strandings of hundreds are common, possibly caused by US Navy sonar.