The baleen whales belong to the parvorder of carnivorous marine mammals; which have the main characteristic of having beards instead of teeth. This group is denominated as mysticetes in the scientific argot.
In this sense, the species that belong to this group have specific characteristics, which are very similar for every one of them; as is the case of their beards, which in turn make the difference with the species of toothed whales. This feature besides being a physical difference, also makes a difference in the behavior of these marine species.
It is important to know, that a parvorder is a type of classification within biology, which involves a taxonomic category; that in this case comes from the cetacean infra order. The whales, dolphins and porpoises are the main specimens of this group. Thus, the right whale, the dwarf right whale, and gray whale belong to this order. Currently, this group of baleen whales is made up of 15 species with the main characteristic of having a beard instead of teeth.
Table Of Content
- 1 Main Characteristics of the Baleen Whales
- 2 Most Common Species Of Baleen Whales
- 3 The Baleen Whales Feeding Habits
- 4 Baleen Whales´ Reproduction and Life Cycle
- 5 ¿How Do Baleen Whales Comunicate?
- 6 The Baleen Whales´ Migration
- 7 Differences Between Baleen Whales and Toothed Whales
Main Characteristics of the Baleen Whales
Following,we list the most outstanding characteristics of these creatures. Their average size reaches up to 20 meters in length, and their weight is around 3 tons. However,there are species which present big variations , like the blue
whales ,which is one of the largest animals in the world, reaching up to 34 m in length and more than 190 tons.
Moreover, the baleen whales are also characterized by having fins and a tail, which were developed throughout the evolution process of their main limbs; in order to get adapted to the conditions of the aquatic environment. However they aren´t considered as agile and dynamics, as the pinnipeds.
Given their physical characteristics, the baleen whales usually reach high speeds when they are swimming. There are evidences that indicate that they can move at more than 37 kilometers per hour.
Their maxillary beard can be mentioned as their most highlighting characteristic, and its main functions is to filter food from water.
On the other hand, as in the case of other whales, they also have two spiracles to carry out their breathing process. This is the main reason why some species of baleen whales, have developed huge capacities to submerge into bigger depths than other species of whales.
In addition to the afore mentioned, another of the morphological adaptations of this specie, is their distinctive thick layer of skin and a layer of fat beneath it; which maintain the body´s temperature even when they are in cold waters.
Now, let´s start our videos session, so you will know more about baleen whales
Most Common Species Of Baleen Whales
The group of Baleen Whales, comprises 15 species that are distributed at the same time in two genera, and these are t the best-known:
These specimens outstand for being the world’s biggest animals, since they can reach even 30 meters in length , and 173 tons in weight. These facts make of them the most prominent-baleen whale species (see article the biggest whales of the world
The blue whales, can be found in almost all the oceans of the planet. However they are considered as an endangered species, since they are very persecuted for hunting purposes, to a point which almost causes their extinction. In this sense, since 1966 the International relevant authorities, have taken all the necessary measures to preserve the existence of the planet’s largest animal, since humans are the main threat for them. Note that given their size, there are not natural predators that represent a real danger for them.
In addition, since blue whales belong to the group of baleen whales, they have many of the characteristics habits of this group, as is the case of their diet, which is based mostly on krill, one the smallest marine species. Their blue and grayish shades,in conjunction with their stylized figure, can also be mentioned as distinctive features of this specie.
Pygmy Right Whale
The pygmy right whale which has the scientific name Caperea Marginata is an specimen which is very difficult to find , so there isn´t enough information about them. They can measure up to 6 meters long, and their weigh is around 300 kgms, which are their more distinctive characteristics.
In spite they are not common, they are quite loved….. watch this video, to know more about them…
On the other hand, we find the gray whale , which is one of the best-known species of baleen whales. They receive the scientific name of Eschrichtius Robustus, and inhabit mainly, in the northern areas of the Pacific Ocean. One of the reasons, why these whales outstand within the group of baleen whales, is that they make one of the longest and most important migrations in comparison with other species. Moreover, they can measure more than 15 meters in length and reach a weight of 20 tons during their adulthood, which are some of their main characteristics.
As their name indicates, these specimen are recognized by the gray color of their body,with irregular spots in white color, that make a characteristic pattern. Their diet is based mainly on krill, that they suck using their beards, which help them filter all the food.
Besides the species previously mentioned, the fin whales also belong to the family of baleen whales. Their scientific name is Balaenoptera physalus. They are positioned as the second biggest animal in the world, which is the most important fact about these whales. In this sense, we can point out that they can reach up to 27 meters in length .
Due to their physical characteristics it is quite easy to recognize them. They have a stylized figure, which has a gray color on the upper portion , and whitish shades on the lower one. These specimens can be found in the major oceans of the planet, either in polar or tropical waters, but currently their conservation status indicates that they are in danger, since like others species of whales, they are threatened by different reasons. Unlike the species mentioned above, the fin whales based their diet on a variety of small fish species, as is the case of squid, crustaceans and krill.
The Humpback Whale
The humpback whale, is also one the best-known species of baleen whales. Among their main characteristics, we can mention that they reach measures between 12 meters and 16 meters in length, and their average weight is around 36,000 kilograms. These whales have very peculiar characteristics, which make them very easy to distinguish from other baleen whales. Their body is a little different than that of the others whales, since they have much longer pectoral fins and a knotty head .
The humpback whale are scattered, throughout all the seas and oceans of the planet, and in the same way than other species of baleen whales; they also make important migrations of up to 25,000 kilometers every year. A distinctive aspect of this speciis, is that they feed mainly in tropical water during the summer season, employing their fat´s reserves during winter as their energy source. Finally we must mention that the humpback whales, usually reproduce in tropical waters, during the summer season.
The Baleen Whales Feeding Habits
Regarding their diet we must start mentioning that they are carnivores although it has been proven that they are able to adapt their diet; according to the conditions in the environment where they are. This means that they can change the species they feed on, as well as the quantity of food. One of the most important aspects, in terms of the alimentation of the baleen whale is as indicated by their name, the use of their beards. From this fact all the behavior is developed at the time of eating, since their beards work as a kind of filter to ingest a considerable quantity of food and extract any type of surplus during the process.
Another of the main references that must be taken into account about their alimentation patterns is that most of them, especially the Antarctic Whales, usually base their diet on krill. It should also be noted that this whole process can be carried out in a group or individually.The baleen whales usually swim with their mouth open, and this way making slow movements, they fill their mouth cavity with water and zooplankton. In other cases, in order to satisfy their alimentary requirements, they submerge into the marine bottoms where they realize a kind of suction of all the organic matter that is found, including small mollusks.
Baleen Whales´ Reproduction and Life Cycle
Since the baleen whales are born until their adult stage, they go through a complex process of development, compared to other species of mammals. It could be considered as an accelerated rhythm, since during all this growth, they reach large measures in comparison to those they had at the first time
According to the aforementioned, we have the example of the blue whale which is the biggest animal in the
world. The fetus of the blue whales gains weight at a rate of at least 10 kilograms per day, and later when they are born, this rate can increase up to 80 kilograms per day, during the entire lactation process,
This is the reason why from their birth, and in the first moments of their lives there is a considerable increase of corporal weight. It is more than 17 tons, and they also reach big measures, as far as the length goes from 7 meters on average up to 16 meters long.
In this sense, since their birth, they go through a continuous development; complying with all the stages of their life cycle and satisfying all their needs. So, when they are between 5 and 10 years old, they reach their sexual maturity, that is the capacity to reproduce. In this stage baleen whales have huge measures, such as 20 to 24 meters in length, being a considerable difference to the measures presented at the time of birthwhen they are born of a whale can have a duration of 80 and up to 90 years. Another interesting fact, is that the offspring are born precocious, since they need to swim in aquatic environments to be able to fulfill the corresponding needs to continue with their development.
Among the conditions and requirements that must be fulfilled, during the first stages of their life cycle, we should mention the temperature of the water, which must be warm. This is the reason why many species migrate to the warmest waters to give birth, preventing this way any kind of problem with the development of their offspring.
The lactation period of this specie, usually lasts from 7 to 11 months, which is another aspect that must be highlighted.
There are others interesting facts about this specie, which we list following:
- The humpback whales can become pregnant after giving birth, while the right whales, must wait an interval of three years in order to be pregnant again.
- There are evidences that indicate that for each mother a single baby is born
- These whales are considered promiscuous, since they don´t establish any type of bond with their partner. In the same way they are considered polygamous, this is because a male can mate with more than one female.
¿How Do Baleen Whales Comunicate?
Baleen whales have developed a complex system of communication, which is based on vocalizations. It is important tomention that all whales have the ability to emit sounds that they use as a way of communication. So, this kind of songs, are quite important especially during the breeding and reproduction of this specie.
Moreover, we have the case of the blue whales , which emit the longest and strongest beeps due to their large size. These sounds last around half a minute and they can be listened to more than 100 kilometers away. These amazing sounds are caused by roars and moans that keep an specific pattern which in some cases may have a duration of 10 minutes, when they are repeated for several hours.
here they are
The Baleen Whales´ Migration
The migratory habit of the baleen whales, is another of their distinctive characteristics. They make this journey every year, looking for accumulations of zooplankton; since according to the climatic conditions, the amounts of krill, also vary. This is the reason for their migrations, during the sunniest months of the year; which occur during the spring and summer seasons.
However, they also make important movements during the winter months, looking for tropical water areas for reproduction and procreation purposes. As we have previously mentioned, these kind of waters fulfill the required conditions for newborns; which in their early ages, don´t have the important layer of fat, that covers their body in very cold waters. According to many specialists, if they stay in cold waters, newborns could even die, because they wouldn´t be able to get adapted; to this type of condition.
Migrations represent a very distinctive characteristic ; made by different species of whales, and the most outstanding one, is carried out by the gray whales. These specimens travel more than 20,000 kilometers, which is a sort of feat for an animal species.
Differences Between Baleen Whales and Toothed Whales
It is important to know, that whales can be classified by having beard or teeth. There are many differences that occur in this classification; as their name indicates, the toothed whales have teeth and baleen whales, have a peculiar type of beard instead. This fact makes some differences, both in their behavior; as in their way of getting adapted to the aquatic environment.
On the other hand, the main characteristic of the baleen whales, unlike the toothed whales; is that their feeding method consists of a filtering system, that is performed with the help of their lower jaw. In this way, they have the capacity to suck a lot of water; including big amounts of food, eliminating then the excess of water, taking advantage of the nutrients from the food ingested.
In spite of many beliefs, the toothed whales can´t chew their food; the function of their teeth, is to grab large and considerable pieces of food , to consume them. So, there is a big difference between the feeding methods of these whales; according to their morphologic characteristics. Therefore, it can be said that baleen whales, only can eat small pieces of food; while the diet of toothed whale, is based on big pieces.
The behavior of these creatures, makes also a difference between them. Toothed whales tend to be more violent and aggressive; compared to the behavior t of the baleen whales. The aggressive behavior, defines the position of a toothed whale, during the breeding season; an aspect that is not remarkable in the case of the baleen whales.
According to the aforementioned, the behavior is also an important characteristic of these species. In this sense, it´s important to know that the toothed whales are aggressive; even when they get in touch with humans. On the other hand, all the species of baleen whales are known for being friendly, in these kind of relationships; since they are usually found in coastal areas. It is for this reason, that toothed whales are considered dangerous animals; but when we talk about baleen whales, the story is quite different.
These species are also quite different, in terms of their sizes. As we already know, the baleen whales are usually larger; than toothed whales. So, according to their morphology, the baleen whales have two spiracles; to perform the whole process of breathing ( see the article; how do whales breathe ); while in the case of the toothed whales, they only have one spiracle.
Baleen whales, can´t swim at high speeds; while toothed whales have the ability to swim a little faster. It must be noted, that baleen whales don´t have dorsal fins; and in the case of toothed whale species, they have at least one.
In the same way the different species included in the group of baleen whales, unlike the toothed whales ; are threatened by the whale´s hunting, since they are less aggressive. So, they are the main victims of human practices (see article: hunting and whaling of whales.
finally, we leave this illustrative video for you…