It is said that Marine Animals are those that spend their entire lives, or at least a very long period of it, in the waters of the seas that exist. There are many types and with very different characteristics, of multiple species, sizes and colors. There are dangerous and harmless ones and in this article we are going to tell you many things you should know about them.
What are the Marine Animals?
Marine animals are those that spend their lives, or a significant part of them, in the waters of the seas. It's important to consider that three-quarters of our planet Earth is covered in water, so it's quite obvious that there must be countless species and types of marine animals living there. However, we must also point out that these are the species most threatened by the danger of extinction, due to causes such as environmental pollution and fishing practices. If you wish to delve deeper into this topic, consult more information about the types of marine animals and their characteristics.
It should be explained that there are already hundreds of marine species that no longer exist or are in danger of ceasing to exist, which is why, today, there are many marine animals that we probably cannot even get to know about them. or to know, although here we will try to give you a summary of the data that exists about them.
Classification of Marine Animals
From the data and information that is handled regarding marine animals, a first classification can be made into two types:
- Those that do not need to spend their entire life in the water: these are animals that need to carry out an important cycle of their life on land, mainly on the coasts, as is the case of animals that reach the beaches for their reproduction.
That's right, there are marine animals that come to beaches to have their young, either on the shore or on the coast, but it turns out that they feed on other marine animals, which can be fish, and form colonies near the shore, developing next to the water, so they can swim and dive in it for long periods.
An example of this are animals such as penguins, seals, walruses, turtles, crabs and sea lions, which have another common characteristic and that is that they breathe air, that is, they have lungs.
- Those who spend their entire lives in water: these are living beings that are born, grow, reproduce and die only in water, because it is their natural habitat. If they were taken out of the water, they could not live. An example of these marine animals are: the squid, the whales, the octopus or the sea serpent and, of course, the fish.
It should be noted that not all marine animals are fish, on the contrary, there are multiple classes, and even within this classification we should also place seabirds, such as pelicans or seagulls, some mammalian animals, such as this is the case of whales, sharks and dolphins, and we would even find marine reptiles such as sea snakes or sea turtles.
Main Marine Animals
For this article we have decided to take into account 24 of the most important and, perhaps, well-known marine animals, but, as we have said before, there are many kinds and species of these animals, in different colors, shapes and sizes, so we are going to it.
Clams
The first that we are going to explain is a bivalve mollusk that we call clams and that lives in salty waters, protected by shells that have the same shape, usually two that overlap and are capable of living in waters that can be found at temperatures between 5 and 35 degrees.
Whale
The whale is, in principle, a cetacean, a term used to designate all mammalian animals that live in the waters. Its main characteristic is its immense size, and it has been scientifically proven that they communicate by means of sounds, just as dolphins do, which are also marine mammals. They can be found in all the world's oceans, in different shapes, sizes and colors.
You are probably well aware of what a whale is, because you have seen a picture or on a television program, but what we have not yet explained to you is that whales are divided into two classes, those that have a beard and those that have teeth. .
The ones with baleen are the majority of the whales we know. That beard is a structure located on their jaw that acts as a filter or strainer, with which they can filter their food and separate it from the water, mainly plankton and small crustaceans.
Regarding toothed whales, as their name indicates, they are the ones that have teeth and, for that reason, they are carnivorous, so they feed by hunting their prey.
Seahorse
It is very interesting, due to its characteristic and distinctive appearance. Its real name is hippocampus, but it is referred to as a seahorse because of its shape, which resembles a horse with a very long snout. It is a true beauty of the sea, and in addition, its structure and customs are very particular.
The males have a pouch, similar to that of kangaroos, where the eggs are incubated. In this marine animal, the male is responsible for caring for the eggs until the young hatch and emerge from the pouch. Currently, science has discovered up to 40 different species of seahorses.
Squid
It is a carnivorous teutid mollusk cephalopod. Trying to make a classification of them is very difficult because there are about 300 species and 29 families of them. Their main characteristic is that they have eight arms and, in addition, they resemble octopuses because they have two tentacles that have suction cups.
Crab
The crab is a crustacean that has five pairs of legs and is characterized by walking sideways, there are also more than four thousand species. It belongs to the family of arthropod animals, they have an exoskeleton that functions as a protective barrier from the environment that surrounds them and in many cases, the first pair of legs are a kind of pincers or pointed pincers.
They can be found on beaches and in rivers, because there are both freshwater and saltwater crabs, but their most common habitat is the sea coast. If you want to learn more about the habitat and characteristics of marine animals, visit the related article on marine mammals.
Sea Conches
If we refer to a snail, you will immediately imagine an animal that moves very slowly, however these little animals have some curious characteristics to show us. One of them, for example, is that there are snails that hibernate during the winter and wrap their bodies in a layer of mucus to prevent their bodies from losing moisture. But it turns out that if they are in a dry season, they can still hibernate during that time to try to survive in adverse situations. It has been documented that there are snails that can live 5 years and others that in the wild can live up to 25 years.
Coral
They probably look like plants to you but believe it or not, they are actually aquatic animals. You may have noticed that they have multiple colors and different shapes that are very attractive and that they live in groups or colonies that create beautiful reefs or beautiful coral barriers.
It has been proven that there are about 2500 species of marine corals. One of their characteristics is that they do not have a backbone and they are very simple forms of life that can be found in tropical and subtropical areas, although several species have also been found living in colder waters, and even in the Arctic.
Dolphin
It is the friendliest marine mammal that exists. Everyone loves it, but mainly children, because of the noises it makes to communicate and because it is a marine animal that likes to play. They are animals that breathe air, therefore, they always remain close to the surface and can travel immense distances, they can dive, although they do not do it for more than fifteen minutes.
According to scientists, this is one of the most intelligent animals in existence and possesses a resonance system in its skull that functions like a kind of radar when it wants to find food, as well as measure distances for swimming. These animals are very social, especially with humans. If you want to know more, you can find information here about animals that cry like babies.
Starfish
Indeed, it is an animal that lives in the seas and oceans of the world, but we warn you that it is in danger of extinction, mainly due to the environmental pollution that has been produced. It is an animal that does not have a skeleton, that is, it is an invertebrate with five arms that end in a point, a characteristic that gives it the appearance of a star.
It belongs to the echinoderm family and lacks a brain, although it does have a very complicated nervous system. It is an animal that is photosensitive, which means that it is bothered by light and also when the temperature changes, it only lives at the bottom of the sea.
Seal
They belong to the family of marine pinnipeds, or they are mammals that have managed to adapt to marine life. There are 19 species of seals that inhabit coastal areas located throughout the planet except for tropical areas.
Due to the amount of fat they store under their skin, they can survive very low temperatures. Their diet is based on fish, crustaceans, cephalopods and they even eat penguins, as well as other seals that they hunt, so they are cannibals. They use their long whiskers to detect vibrations and find their prey.
Prawn or prawn
These are crustaceans that belong to the decapod order and live on the seabed of the oceans. There are many different species of shrimp. They do not have a skeleton, so they are also invertebrates and have an exoskeleton. Their main food is algae, fish and plankton.
Seagull
They are very common in America and Europe. Gulls can weigh between 120 grams and 1,75 kilos, depending on the species to which they belong. They have great ability to move on the water and are birds that are very intelligent and social. Their main food is insects, some fish, crabs, squid, and some vegetables.
manatees
They are mammals characterized by their enormous size, but their diet consists of plants, particularly vegetation. They are very slow-moving and lazy, and their life expectancy can reach up to sixty years. They are marine animals that breathe air, as they have lungs, and they typically live primarily in temperate waters.
Jellyfish
They are thought to be the oldest marine animals in existence, as jellyfish fossils have been found dating back more than 700 million years. More than two thousand species have been cataloged and, depending on the type of jellyfish in question, they can live on the surface of the seas or in the depths of the oceans.
They do not have a brain but they do have a highly developed nervous system, which has receptor organisms that help them find their food. There are species of spectacular color, while others may only be white and even transparent.
Jellyfish, as we have said, can live in very different places, both on the coast and at the bottom of the sea and are from the pulmonata family. One characteristic of them is that they have gill filaments through which it is convenient for them to feed on plankton. They are gregarious marine animals, that is, they live in groups and their life expectancy is about seventy years.
Moraine
From the behavior it has shown, it can be said that it is a very aggressive fish. Very good size specimens have been found, it has the shape of an eel, because it does not have ventral or pectoral fins, it also does not have scales. Its habitat is the rocky areas and coral reefs of subtropical and tropical seas.
Orca
It is a cetacean that belongs to the delphinida family, which means, although it may seem surprising to us, that in principle they are dolphins, more specifically, they are the largest species of dolphin that exists, they are mammals and they breathe air, although Their habitat is water, since they could not survive on land due to their weight and bulky size.
They have also been called killer whales, because their food is made up of other mammalian animals. They live in a gregarious way in groups that can have between 6 and 60 individuals and their gestation period is about 17 months.
Guppy fish
It is a tropical freshwater fish that is highly appreciated by enthusiasts around the world for placing in aquariums. It is a very beautiful vision, with many colors and one of the reasons for being so popular is that they reproduce very easily in captivity. In the world, so far there are 300 different kinds of guppies.
penguins
Although it may seem amazing to you, penguins are birds, but they do not fly, and their food is made up of other marine animals that are in the ocean, such as shrimp, fish or squid, among many others. One of the most beautiful penguin species is the emperor penguin, which is a very large species and can measure just over a meter, weighing up to 35 kilos. Its natural environment is cold climates, but there is also a species that lives in the north of the Galapagos Islands.
Octopus
It is a cephalopod that has eight arms in the form of tentacles that are covered by twelve suckers. There are about 300 different species of octopus and it is a highly intelligent marine animal. In the event that they feel threatened by a predator, they are capable of expelling ink to escape and defend themselves. Their life expectancy in the sea is two years, but in captivity they have managed to live up to five years.
Sea snake
It was called Hydrophiinae and also poisonous snake. It is one of the few animals that can live both in water and on land. Its skin has very colorful colors and its habitat is located in the Pacific Ocean and the Indian Ocean. Another characteristic is that they have scales and that they use their tail as a propellant to swim.
Shark
It is another marine animal that is a mammal, and it is the one with the worst reputation among human beings, due to the attacks on bathers that have been carried out by them, especially in southern Africa and Australia. But, unlike other marine mammals, it does not need air to breathe, because it does so through gills.
It moves in the water due to its caudal fins and one of its excellent physiological characteristics is that it manages to stay afloat due to its huge and fatty liver. They are cartilaginous animals, they do not have a skeleton and an interesting aspect is that they shed their teeth all the time and grow all the time of their existence.
Sea turtle
These are cold-water reptiles that we can find in the tropical oceans during the season in which they lay their eggs, abandoning them, and they do so on the coastal beaches, burying them in the sand, from which the eggs take heat so that they the pups are born.
When these little turtles are born, they will start a race towards the sea to start their life as individuals, until when they reach maturity, they will mate and return to the beach where they were born to also lay their eggs.
Marine Animal Families
In this part of the article, we are also going to examine marine animals but from the point of view of their taxonomic classification, but we are going to begin to know something more about what are vertebrates and invertebrates.
Invertebrate Marine Animals
This word is used to refer to animals that do not have a bone system, mainly because they do not have a backbone, and can be classified into:
Echinoderms
These are marine animals among which are the stars and sea urchins. They are a family of animals that normally have a very spiny section inside, hence their name, which in Greek means spiny skin. Currently there are about 7 thousand of these species in the ocean.
All of them are complex marine animals, and we can see that their bodies are covered by a shell or exoskeleton composed of calcareous plates and spines.
Sponges
These are primitive marine animals that have a cover full of small holes and pores through which they are allowed to inhale water, that is, water enters and leaves them through those holes and they also have a hole greater that receives the name of osculum, through which they feed. Sponges do not have tissue or body shape and there are currently about 9 thousand types in the seas.
marine worms
They are actually called equiuros, nemertines and flatworms. A special feature is that, despite being all marine worms, they are not related to each other, although they all have a particularly soft and quite elongated body. Marine annelids or polychaetes are hairy worms and their body is made up of rings.
rotifers
Rotifers are marine animals that can usually be found in salt water. Most of them have a ventral area that is crossed by ciliated bands, whose function is to create a current in the water so that the food that is around them is trapped in them.
Occasionally, some species of rotifers live inside tubes or capsules, which is why they are also sessile.
Seafood
Crustaceans are marine animals that belong to the family of arthropods and have an exoskeleton in the form of a calcareous chitinous shell. They have a body divided into segments and are muscular. They are a very important part of the invertebrate class.
Molluscs
They are characterized by having a soft body, which is why they are normally protected by a shell and can be from land or sea. They feed through an organ called the radula.
Among those that are better known are bivalve-type molluscs, such as clams and oysters, gastropods, which is the case of snails and slugs, or cephalopods such as octopuses, cuttlefish or squid.
Vertebrate Marine Animals
They are marine animals that have a bone system, mainly a spine, among which are:
Fish
It is a very large family of marine animals whose body is made up of a gill apparatus that allows them to breathe by absorbing water through them, and fins with which movement is facilitated. It is common for them to have very scaly skin, although there are fish that do not have scales.
They are the most important part of the vertebrate marine animals and their life takes place entirely in the water, as is the case with sharks or manta rays.
reptiles
It is part of the group of vertebrate animals, one characteristic is that its skin has scales and, of course, they crawl around the place where they move, it has the power to go out to sea level and from the coast, as is the case of snakes, crocodiles and sea turtles, all reptiles that can survive in salt water or fresh water.
Mammals
It is the most relevant group of vertebrate animals, which usually have a pulmonary respiratory system, which is why they need to go to the surface to breathe air and their way of reproduction is viviparous.
Dolphins, killer whales and whales are mammalian animals that, although they are animals that live under the sea, they need air to breathe and they do so through their spiracle, which is a hole in their head. Other mammals, such as sea lions or seals, can live both in water, whether fresh or salty, or on land, as is the case with otters.
Where was life born?
We will answer this question by saying that life was born in the sea and the number of species that exist in the sea is immense, so much so that we cannot guarantee that they have all been scientifically discovered and classified by man. Almost all known species are used as a means of food by many peoples and societies.
We tend to believe that all marine animals are fish, but as we have just seen, this concept is wrong, because there are species that have their habitat in the sea or near it in all animal species.
Indeed, there are mammals such as whales and seals, birds such as pelicans, seagulls or penguins, which, despite not flying, are birds; reptiles, such as the turtle or the sea snake. What does not exist are amphibians that are marine, and it is thought that this is so because amphibians are the product of the evolution of other animal species that came out of the sea and adapted to the land.
It has been proven that spectacular species coexist in the marine environment, capable of using camouflage techniques to defend themselves, as in the case of octopuses and squid, which take on the color and appearance of stones or the seabed. in which they are.
There are animals that amaze for being very intelligent, as is the case with dolphins, which are probably the most intelligent animals on earth, and have a very specialized way of communicating, since it has been proven that they are capable of creating strategies to hunt in equipment or to be able to protect yourself from your enemies.
You've also probably heard stories about dolphins helping survivors who have been shipwrecked or often accompanying fishing boats, pointing out the places where the herring schools go fishing. But you must also have heard that many of these marine species are in danger of extinction.
Marine animals in danger of extinction
There is no single reason that threatens the life of marine species, on the contrary, from pollution to indiscriminate fishing, without those responsible for the fact that we are about to witness the disappearance of many species.
Something that we can affirm is that the main agent that has put these species in danger of disappearing is man, with his disrespectful attitude towards nature and his desire for greed.
Forms of fishing harmful to marine animals
In the case of forms of fishing that have no respect for the marine environment, we have the case of the practice of trawling, with which the nets used not only catch fish, but literally it sweeps the bottom of the sea, dragging, as its name indicates, all the forms of life that it finds, from plants and corals to corals and crustaceans.
Another form of fishing that has been extremely detrimental to marine species is massive fishing, with which creatures whose reproductive cycle lasts for years are fished indiscriminately, so their population decreases by leaps and bounds.
To this we must add that, in this type of fishing, there is no discrimination between small and large animals, although the former have no commercial value, since they are collected together with the large ones, to be later thrown into the sea as waste, which also then results in a source of environmental pollution. A case of this danger is that of the blue whale, the sperm whale or the white whale.
Destruction of the marine environment
But the most relevant threat to marine species is the loss of their habitat, with water pollution and throwing garbage at the bottom of the seas. The most demonstrative case of this pollution is the large amount of plastics that is currently floating adrift somewhere in the Atlantic Ocean, which is the size of a huge city.
Marine animals in danger of disappearing
In this section of the article, we'll show you some marine species and animals that are in danger of disappearing, such as manatees, blue whales, dolphins, monk seals, sharks, otters, king salmon, and several others. Please note that this list is tentative, as more species are added each year, and we are doing little to preserve them.
Dolphin
They are small mammalian cetaceans that have teeth, so they are carnivorous, and their habitat is the temperate waters of the seas, mainly in the Pacific and Atlantic oceans.
They have a very aerodynamic silhouette and small fins. Specimens have been found measuring up to four meters and weighing approximately 300 kilos. They are gregarious animals, so they live in groups of at least six individuals.
They are in danger of extinction, due to the fact that fishermen capture them to sell them to aquariums or sacrifice them, as is the case in Korea or Japan, places where they are esteemed as an exquisite dish.
Blue whale
Blue whales are marine mammals, from the class of cetaceans. Its size can be enormous, reaching up to 35 meters long and weighing up to 2.500 kilos.
These whales have smooth skin, provided with a layer of fat inside that thermally shelters the animal, as if it were a thermal suit. The ability of whales to swim is due to their tail fin, which is always exposed horizontally.
These whales are in danger of disappearing because their entire body has been used for commercial purposes since time immemorial, because oil is produced from their fat, their meat produces food for human beings and for other uses, because it is rich in protein and its Bones can also be used as food, in crushed form, or as an ornamental piece or material to make pieces of that style.
manatees
Manatees are marine mammals that are in great danger of disappearing. For centuries, specifically since the fifteenth century, these mammals were confused with mermaids, thanks to the shape of their tails. The manatee has even been classified as a sirenid.
Today it is thought that the marine myth of the sirens had its origin in the description of the manatees, who also have underwater communication, through the emission of short-wave sounds, which can also be perceived by the human ear. , being confused with the songs of the sirens.
Shark
The indiscriminate hunting of sharks is the primary reason why these impressive marine animals are in danger of disappearing. In fact, practically fifty percent of the shark species that inhabited the seas have already become extinct, leading to the conclusion that the shark population has become extinct by ninety-five percent in some species.
Moraine
The moray eel is a fish that has a long and narrow body, in the shape of a snake. It is an animal that is very peaceful, although it may not seem so from its appearance. Its habitat is coral reefs, and its body is particularly adapted to them, which allows it to wander among corals to feed and live in cavities or hollows.
One of its characteristics is that the skin of the moray eel is poisonous, another that is very terrifying is that it has two pairs of jaws, which allows it to have a very particular method of hunting and is that it can remove one of those jaws from its mouth. to catch its prey and put it in its mouth, and the second jaw will start to chew it.
Monk Seal or Friar Seal
The friar seal whose habitat is the Mediterranean, is one of the most peculiar species that exist, because it does not have ears. It is said that this species is in serious danger of disappearing in the very near future, because eighty percent of the monk seals have died and there are only 250 adult specimens.
Royal Salmon or Chinook
King salmon whose habitat is the Pacific Ocean, between Japan and California, is a species that is becoming scarce. For this reason, some biologists think that it is in danger of disappearing. There are biologists who think that it is in danger of disappearing, because the conditions required for it to survive are clean waters and rising temperatures.
sea otter
It inhabits the North Pacific Ocean and is a unique species that belongs to the genus Enhydra, but the sea seal has been disappearing from Japan to Mexico. The reason is the indiscriminate hunting to which it was subjected for its skin between 1741 and 1911. Poaching continues today and contaminant spills have also affected it.
Napoleon fish
It is an attractive species, whose habitat is very wide, because it ranges from the Red Sea to Australia. These are fish that can measure up to two meters and weigh up to 200 kilos. The interesting thing about these fish is that they are hermaphrodites and they are all born female.
Their life expectancy is 20 to 30 years and they are not a danger to humans, but they are in danger of extinction due to pollution and indiscriminate fishing.
Giant octopus
It is a marine animal that does exist, although the reality of its size has been exaggerated by the stories and legends that have been told. They normally measure five meters long, although specimens of nine meters have been found.
Measures must be taken in favor of marine animals
The marine habitat is beautiful and, in many of its areas, unknown to man, but it is full of spectacular and striking species, which must receive due treatment, protection and respect from us, therefore man has to take measures that tend to preserve this environment.
The palliatives that must be implemented are many and urgent, the first of which is to abandon any practice, whether commercial or not, that means causing damage to the seas and the species that inhabit them, with which we can contribute by doing our part, implementing measures that protect the beaches.
That is why there are organizations that promote the care of the seas and their species and carry out programs that aim to repopulate marine animals in danger of disappearing through captive breeding. But these measures will not succeed if we do not change the way we treat the oceans.
Likewise, our industrial form of exploitation has given rise to an absolutely dangerous factor for marine animals, which is global warming, producing serious climatic changes, which have affected the life cycle, not only of marine animals, but of the fauna in general.
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