With a length of around 10 ft. long the melon-headed whale is considered a mid-sized dolphin.
This species of dolphin prefers swimming in warm waters and can be found living throughout the tropical/subtropical oceans of the world.
The melon-headed whale is known to frequently congregate into large pods of 100 – 1000 dolphins and may be seen swimming alongside other species of dolphin.
Physical Characteristics and Appearance
When fully grown the melon-headed whale can reach lengths of nearly 10 ft. long and can weigh over 450 lbs.
These dolphins have an oval-shaped body that tapers towards the flukes and the head resembles the shape of a melon and is triangular in nature as it runs towards the mouth.
The dorsal fin is a little large, triangular and tapered back in nature near the middle of the back.
The flippers are also tapered back and somewhat sickle shaped along the dolphins sides.
In terms of color they have a gray colored body from the neck to the flukes and a darker gray face while the belly area may appear to be a light gray to white coloring.
Diet and Hunting Methods
They may also occasionally consume various crustaceans.
When it comes to hunting for food at night or in dark areas these dolphins are equipped with echolocation and are able to bounce sounds off of objects in the area in order to determine the location, size, density, speed and direction of the objects surrounding them.
Their echolocation is so advanced that they can easily determine whether or not the objects in their environment are food, a predator or an inanimate object.
Given there large pod sizes it is likely that they hunt in groups and use echolocation to organize hunting parties.
Habitat and Migration
The melon-headed whale prefers living away from the coastline can be found traveling throughout the worlds tropical and subtropical climates.
They have been spotting in a number of different locations such as South Africa, Southern England, Hawaii, Ireland and the Philippines among other tropical/subtropical regions.
As far as migration is concerned these marine mammals aren’t known to perform long migration trips.
Social Structure and Communication
The melon-headed whale communicates using a variety of high-pitched clicks and whistles in order to socialize and share interests with other dolphins.
As a species these marine mammals are a very social group that are known to commonly travel in large pods of 100 – 1000 dolphins.
During certain aggregations pods may grow to include several thousand dolphins.
When traveling in pods these marine mammals have been known to change course in unison in repeated sessions during their travels.
While they tend to shy away from large boats and other scary objects they do display some active behaviors.
For example dolphins that feel they are in a comfortable and safe area may be seen making repeated shallow leaps, breaching the water, spy-hopping or bow riding for short distances behind some boats in areas that aren’t overly commercialized.
They have also been spotted traveling and interacting with other species of dolphin in their local habitat.
Depending on their location some dolphins have been spotted spending the majority of their day resting at or near the surface of the water in a fairly inactive manner.
It is suggested that their behavior may differ in different environments based on pod behavior and human interaction.
Given their large pod sizes these marine mammals have also been observed performing large scale stranding’s where as many as 50 dolphins may end up beaching themselves on land or in shallow waters.
Some researchers suggest that noise pollution may be the cause of some of these beachings.
Breeding and Reproduction
The average gestation period for the melon-headed whale is assumed to be around 11 – 12 months.
After birth the female dolphin will nurse her child by feeding it milk until it is able to hunt and survive on its own.
The age of sexual maturity, reproduction habits and average number of children that are produced by the female melon-headed whale are unknown, however some information suggests that females reach sexual maturity between the ages of 10 – 12 while males apparently reach sexual maturity around the age of 15.
These dolphins are believed to have an average lifespan of at least 30 years, with males living 5 – 10 years less than their female counterparts.
The melon-headed whale is known to face several humans threats which may include:
- Waste/chemical pollution
- Noise pollution
Bycatch– Bycatch occurs when a melon-headed whale swims into a fishing net that is intended for capturing fish (usually on commercial fishing hunts) and gets unintentionally caught in the net where it drowns due to its inability to resurface for fresh air.
In some cases a dolphin may end assume it has found an easy source of prey (the fish captured in the net) or it may end up swimming into the net because it didn’t realize it was there.
In either case this can lead to death as the dolphin is unable to rise back to the surface.
Hunting – It is believed that that melon-headed whale may be hunted by poachers that are interested in either selling their meat for human consumption or using the dolphins meat as a form of bait for capturing other ocean prey.
Waste/chemical pollution – In commercial areas the melon-headed whale may come into contact or be affected by waste and/or chemical pollution.
These forms of pollution can have a direct affect on the dolphins health, affect the dolphins food or cause complications with reproductive behavior and birth.
Noise pollution – It is often suggested that noise pollution from man-made tools and noisy machinery (i.e. planes, sonar, explosives, etc..) may interfere with the dolphins echolocation and sense of hearing.
These noises can cause dolphins to lose their sense of direction and may even cause tissue damage to the marine mammals ears and brain.
As the earth becomes more noisy growing concerns regarding the potential affects this is having on marine mammals is continuing to escalate leading to new research studies on the topic of noise pollution.
In regards to natural predators it is unknown whether or not these marine mammals face threats from sharks or other large predatory ocean animals.