The Blainville’s beaked whale, sometimes known as the dense-beaked whale, are a species of whale that can be found in deep, warm waters all over the world.
They are named after Henri de Blainville, the 19th century French zoologist who discovered the species.
There is little hard data regarding their lifestyle and behavior.
Physical characteristics and Appearance
Unlike most beaked whales, male Blainville’s beaked whales are easy to identify due to two large, tusk-like teeth that stick out from the middle of their lower jaws.
These teeth are usually encrusted with barnacles, and they are found on adult males.
These distinctive teeth are the reason some males have scars and scratches on their sides, due to fighting with other males over a mate.
Female and juvenile Blainville’s beaked whales also have these teeth, but they are hidden under the gums.
They also have a pair of throat grooves beneath the lower jaw.
Although the color of these whales varies a little, the upper side of these whales tends to be a grayish brown or gray-blue, while their underside is a lighter gray.
Some species have white spots on their bodies.
These whales have a dorsal fin about two-thirds of the way down the back, and the spray is aimed toward the whale’s head.
When these whales exhale the spray from the Blainsville’s beaked whales’ blowhole is difficult to see.
Like other beaked whales, their beaks are small, but distinct.
In terms of size these whales grow to a maximum length of 14 – 15 ft. and weigh between 1,800 and 2200 lbs. when fully matured.
Diet and Hunting Methods
Because they are such deep divers, Blainville’s beaked whales hunt mainly in deep waters and use echolocation to find their prey.
In addition to using echolocation to search for food it also helps them navigate the ocean and avoid colliding with other objects since echolocation uses sound to help them identify objects in their surrounding rather than having to rely on eyesight, which is all but useless in dark waters.
There are not many specifics known about the Blainville’s beaked whales’ diet due to the fact they they hunt for prey at levels that are beyond most researchers capabilities.
However, because these whales do not have functional teeth except for their tusks, it is suspected that they eat mostly marine invertebrates, such as:
• Armhook squid
• Cockeyed squid
• Glass squid
• Octopus
They may also fish and various crustaceans.
Due to the fact that they have so few teeth it is believed that they consume their prey whole as they are likely incapable of chewing their prey.
These whales are deep divers and can dive to depths of 4,600 ft. and hold their breath for over and hour when searching for food.
Shorter dives may consist of a series of 800 ft. dives with 10 – 20 minute underwater intervals, which may be part of their recovery process after an extended diving session.
Social Structure and Communication
Blainville’s beaked whales have been found alone or in social groups of between 3 and 7 whales, although sometimes they travel in groups of as many as 12.
When traveling in groups these marine mammals have been observed swimming in unison while diving and surfacing in a cohesive manner.
While they may form groups with other whales there is no guarantee of permanence and individual whales may leave a particular pod and join another group.
Sometimes individual pod members may leave their group for several years or never return to their previous pod
Reproduction and Lifespan
There is not much concrete information about the breeding habits of Blainville’s beaked whales, except that they reach sexual maturity around the age of nine.
It is likely that males use their tusks to fight over a preferred female, which accounts for the scars left in the males’ sides.
A female Blainsville’s beaked whale births only one calf at a time, whom she then nurses until it is able to hunt and survive on its own.
Nursing their calf involves defending their child and nurturing it by feeding the baby whale with milk which they child suckles from its mothers nipple.
The nutrients and fat of the milk are essential for healthy child growth and nutrition and are the child’s primary source of food during its first months.
The average lifespan of these whales is unknown.
Blainsville’s beak whales are beautiful but mysterious creatures, and, with persistence and good luck, we can study their behavior more in the future.
Habitat and Migration
Blainville’s beaked whales are found in tropical and temperate waters all over the world, and they are primarily a deep-water species.
They prefer tropical and temperate waters that are at least 6,000 ft. deep.
Threats
Because there is so little information available on Blainville’s beaked whales, it is difficult to understand exactly what threats they face.
Although Blainville’s beaked whales occupy a place on the International Union for Conservation of Nature (IUCN) Red List of Threatened Species, their conservation status is currently listed as “data deficient.”
They are rarely the specific targeted of whale hunters, but they do face some threats such as:
• Bycatch (i.e. unintentional catch) in fishing nets
• Acoustic trauma caused by high-intensity, low-frequency sonar employed by US and NATO naval vessels
• Ingestion of marine garbage and pollution
When it comes to acoustic trauma there have been observations of mass strandings occurring in areas where intense mid-frequency sonar has been used, which suggests that they are very sensitive to disruptions caused by artificial man-made sounds.
It is possible that their echolocation and ability to communicate may be severally diminished when interfered with by other unnatural noises.
One observation of the stomach contents of a stranded beaked whale found in Brazil indicated the ingestion of plastic materials which suggests that at least some beaked whales may be affected by garbage and other forms of pollution.
Predators
Little is known regarding potential predators to Blainville’s beaked whale however it is believed that when these whales perceive a threat they maintain an unobtrusive behavior by becoming silent and avoiding communication when near the surface of the water.
This is assumed to help these marine mammals avoid being attacked by killer whales that are hungry and looking for food.