The pygmy right whale is a marine mammal that is part of the baleen whale suborder and belongs to the cetacean family which is made up of whales, dolphins and porpoises.
Because this whale is a marine mammal it shares a number of characteristics with other mammals including breathing air, being warm-blooded and giving birth.
While the pygmy right whale carries the same name as other whales within the “right whale” family this baleen whale is actually not considered part of the right whale family.
This whale can be found living in the Southern Ocean and is considered the smallest of the baleen whale species and is even smaller than some of the toothed whales.
While little research has been gathered on this species regarding its lifestyle and social structure we have gathered some information which can give us a better understanding of this sea creature.
Physical Appearance and Anatomical Characteristics
The pygmy right whale has a dark gray upper body with a light grey belly and lower body that extends from its jaw to its tail.
When observed from a distance this whale is similar in physical appearance to the Antarctic minke whale and can lead observers to be confused and misled by its appearance other than the fact that it is smaller in size than the minke whale and has somewhat noticeable distinctions with its jaw and flippers.
They also have a bow-shaped dorsal fin which is located about 2/3 down the length of its body.
In terms of size the pygmy right whale is relatively small and can reach lengths of up to 21 ft. and weigh over 7500 lbs., however most whales measure closer to 15 – 20 ft. in length.
In fact the pygmy right whale is considered to be the smallest marine mammal in the baleen whale family.
Diet and Hunting Methods
From information that has been collected from the stomachs of these whales it has been assumed that their diet consists mainly of copepods and euphausiids, however observations of the stomach contents of beached/stranded whales shows that krill is also a part of their diet.
Despite their small size these whales are part of the baleen whale family and as such they possess baleen plates and bristles that they use to separate their prey from the water.
Although nothing is known about their hunting methods their small lungs and heart suggest that they are not deep divers so hunting for food likely takes place at or near the surface of the water.
Habitat and Migration
As stated earlier the pygmy right whale can be found swimming in most parts of the Southern Ocean; however their slow nature and small pod sizes (these whales typically travel alone or with 1-2 other whales) make them difficult to find and observe.
Some of the most common places where these whales have been spotted include Australia, South Africa, Chile and New Zealand.
In certain locations these marine mammals may maintain a fixed location throughout the year as beaching’s/stranding’s have been observed in certain areas regardless of the time of year.
As a species they appear to prefer living in cool to cold waters of the southern hemisphere.
Social Structure and Communication
Unfortunately very little information exists regarding their social structure.
If these whales are similar in social structure to other baleen whales than it can be assumed that they communicate using loud low-pitched sounds and travel in small pod sizes that grow larger during certain social events.
In most cases these whales have been observed traveling alone or in pairs, however during certain aggregations as many as 100 pygmy right whales may be seen gathered together.
They have also been observed inhibiting areas alongside minke whales, pilot whales and dolphins.
These marine mammals are described as fast and strong swimmers, but not much is known about their behavior.
When surfacing these whales tend to remain fairly inconspicuous and in some cases their dorsal fin may remain undetected when surfacing.
From the little bit of data that is gathered about the pygmy right whale it appears that they do not display common tail slapping or breaching behaviors seen in other baleen whale species and aren’t know to expose their tail when they dive.
Mating, Reproduction and Lifespan
Little to nothing is known about the breeding habits of the pygmy right whale.
The average gestation period for whales in general various from 9 – 17 months depending on the species so it is safe to say that these whales also follow similar gestation periods, with estimates for the pygmy right whale ranging between 10 – 12 months.
As with most known whales it is extremely likely that they produce milk which they feed to their young until they are able to hunt and search for food on their own.
Sexual maturity and lifespan remain unknown, however it is believed that sexual maturity is reached when they grow 15 – 17 ft. long.
Threats
Due to the fact that the pygmy right whale is relatively small when compared to other baleen whale species these marine mammals were rarely if ever hunted during the whaling era.
There are no significant records to indicate that they have been hunted by whalers or poachers so nothing can be confirmed regarding this topic.
Occasionally these whales may end up beached or stranded on the shore or beach line due to being sick or injured.
Potential threats include being struck by ships and getting caught in drift nets which can lead to suffocation.
Unlike other whales pollution is less likely to affect these marine mammals as they live in offshore waters.
Research performed on stranded whales also shows low levels of contaminants which suggests they face little threat against being harmed by possible pollutants.
Rare spotting’s of the pygmy right whale indicate that they may be a naturally rare species.
Predators
No significant data exists regarding potential predators so it is unknown whether or not these marine mammals are prayed upon by sharks or other predators.