There are more than 30 thousand species of fish in the modern aquatic fauna. They are distinguished by a wide variety of shapes, colors and unique abilities, compared to land animals. There is not a single shade of color that is not used by the fish. Among this color scheme, one of the leading places is occupied by surgeon fish from the surgical family.
The origin of the species and description
Fish surgeon takes its origin from bony fish that appeared during the poleozoic (about 290 million years ago) and in the process of evolution were divided into two different groups: lungfish, lobe-finned and cartilaginous, bony. By further adaptation, about 70 million years ago, perch-like representatives were formed from bony ancestors, which gave rise to the formation of bony fish of the modern ichthyofauna.
Surgical fish include 6 genera, and there are about 80 species in them and are classified thus:
- kingdom Animals;
- type Chordata;
- class Ray-finned fish;
- order Surgical.
The genus of surgeon fish includes the most species, about 40, for example: striped, pale, Japanese, white-breasted, blue, pearl and others.
Video: Fish Surgeon
Fish of this family are the most striking and extraordinary inhabitants of the oceans and seas. They are relatively small. These are active and at the same time calm herbivorous fish, which are adapted to live both one at a time and can gather in numerous groups, especially during the mating season.
A characteristic adaptive feature of all surgical representatives is the presence of sharp protrusions on the body, employees as a means of defense against the attack of their natural enemies. Where did the appropriate name for this family come from.
Depending on the genus, surgical fish differ in their typical features. So, fish of the genus Naso (trigger fish) have a horn-shaped outgrowth on the head in the frontal region, and its body length can grow up to 100 cm; zebrosomes have a more rounded shape due to high fins; ctenochetes have particularly mobile teeth.
Appearance and features
Externally, the surgeon fish has the following features:
- The body of the fish is flattened on the sides, oval, slightly elongated in the tail direction, in shape. From above it is covered with dense, small scales.
- On the head are large, high-set eyes and an elongated tiny mouth with sharp teeth of various shapes. This structure of the eyes allows her to well view her territory in order to find food and the presence of the threat of predators. And the characteristic mouth makes it possible to eat plant foods of marine flora.
- The fins – dorsal and anal, have an oblong shape. The dorsal fin is made with strong rays that can be pricked.
- The sizes of different representatives can vary from 7 to 45 cm.
- The color of the surgeon's fish varies in a wide range of colors: yellow, blue, green, orange, brown and other shades. If not bright colors prevail in the coloring, then such a fish is distinguished by the presence of variegated spots and stripes in different parts of the body and head.
considered to be a protective device. On the sides of the body near the tail end, in the process of evolutionary development, they have formed a scalpel-like process, which serves as a means of protection in unsafe situations.
Interesting fact: “Based on data taken from travel forums, the most common reason for visiting a doctor while traveling is cuts on the limbs from attacks of surgeon fish, after which they even put stitches on the wound. In addition, such wounds are very painful and take a long time to heal.”
Where does the surgeon fish live?
In nature, surgeon fish lives in the salty waters of warm oceans and seas. It is common in the Indian, Pacific and Atlantic Oceans, in the Red and Arabian Seas, and is also beginning to explore the Caribbean Sea.
An interesting fact: “In 2018, the surgeon fish was accidentally caught by fishermen in the Black Sea which is not her natural habitat.”
Surgeon fish can always be found near coral reefs. Beautiful, winding reefs with many nooks and crannies, rich in algae and peripheton growing on them, serve as her home and source of food.
This fish always tries to be in shallow water, closer to the bottom of the ocean or sea, most often it swims at a depth of up to half a meter. At low tide, she rushes to the stone shores of caves to hide in the depths, and can also wait in lagoons or under reef ledges. During the rising tide, it returns to coral reefs again.
Due to their memorable coloration and relative unpretentiousness in keeping, representatives of these fish species are quite frequent members of the aquarium fish team.
What does surgeon fish eat?
The chewing apparatus of the surgeonfish is adapted for grinding hard and soft plant foods. They have a small mouth, a strong jaw and a set of sharp teeth. They are herbivorous reef fish. During evolution, they changed along with the environment and adapted to eat all the gifts of the reefs. Therefore, fish surgeons are conventionally divided into three groups according to food characteristics.
Surgeon fish that feed on microalgae and filamentous algae. They have a muscular stomach, in which food is rubbed along with sand that has got inside with algae. These are such fish: surgeon mata, olive, dark.
Surgeon fish feeding on algae and invertebrate settlements on the surface of rock ledges, as well as calcareous reef algae. With their sharp teeth, they bite off sections from coral twigs and gnaw off the upper layers of the peripheton. They do not have a muscular stomach. For example: minke whale surgeon, striped, pearly white-dotted, blue gold-backed surgeon.
Surgeon fish feeding on vegetative bodies (thollomas) of large algae. For example: white-tailed surgeon. Some individuals are not averse to consuming the remains of invertebrates and plankton as an alternative food source. And for the immature young of surgeonfish, zooplankton is the main food. If there is a shortage of food in the surgeonfish, they can gather in large groups to search for food.
Character and lifestyle features
Surgeon fish, being in the same territory with their relatives, can live both alone and grouped in pairs or in flocks with a different number of individuals (sometimes up to a thousand). Gathering in such schools during the mating season, these fish use the extravagance of their coloration to find a suitable sexual partner. Despite cohabitation, each surgeon tries to keep his personal space around him.
The nature of these small reef dwellers is not quarrelsome, they get along with other representatives of the fish dynasty without any problems. But males can sometimes show a pointed persistence in the protection of personal territory, thereby controlling “their” females and food. This is often helped by their “secret” weapons. Representatives of this genus of fish are mainly active during the day, and at night they hide in rock crevices and labyrinths of coral reef branches.
Interesting fact: additional stripes and spots appear.”
Thanks to their strong fins, these fish can easily withstand the strong currents of sea and ocean waters.
Social Structure and Reproduction
Fish surgeons are dioecious animals, but do not have special sexual differences. They become sexually mature at about two years of age. From December to July, during the new moon, they gather in large schools to perform the function of reproduction – spawning.
Interesting fact: “Surgeon fish living in the equatorial zone can spawn all year round.”
To spawn, the fish separate from the schools in small groups and swim to the surface of the water. Here, females give birth to the smallest eggs (up to 1 mm in diameter). One female can lay up to 40 thousand eggs. The development of the embryo lasts for one day.
Further, transparent disc-shaped larvae appear, not similar to their parents. They do not have characteristic sharp processes on the sides of the body, but they are prickly due to the presence of poisonous spines on the fins. The larvae actively feed on plankton on the surface layers of water and in about two months reach a length of 2.5 – 6.5 cm. Now they are considered ripe for further transformation into fry. water, fall into small reservoirs, where their transformation takes place within 4-5 days. Their body becomes covered with small scales, a sharp outgrowth near the tail is laid, and the digestive tract lengthens. The fry get used to eating algae, continue their growth and return back to the deep waters of the oceans and seas to the reefs.
Natural enemies of the surgeon's fish
The surgeon fish is not large, however, predatory fish do not mind eating this little one. Especially great danger lies in wait for these fish during the breeding season, when they gather in large schools.
Relatively small fish, such as tuna, tiger perch, and large fish, sharks, can act as natural enemies of the surgeon's fish etc.
Trying to escape, the surgeon fish can of course use its “doctor's” weapon, but given the size discrepancy with the predator, it loses, because a large fish will not notice its injection. Therefore, these little coral reef lovers often use them for hiding.
A sharp appendage, located on the sides of the body near the tail of the surgeon fish, can be used to protect its territory. In the absence of a threat from the outside, these bony protrusions are hidden in the grooves on the surface of the animal's body. When there is a risk, the fish places them on the sides and moves to attack.
Surgeon fish larvae also have enemies, these are crustaceans, predatory insect larvae, jellyfish, from which they protect themselves with their poisonous spines.
Since fish surgeons eat mainly plant foods, their meat cannot be called a delicacy, it is simply not tasty. Therefore, for the purpose of poaching, people did not touch these fish before. But in the face of declining stocks of fish popular for fishing, these representatives of the surgeonfish family were in danger of humans.
For their bizarrely beautiful coloration, people massively catch them for aquariums in which the surgeon fish cannot breed due to difficulties in maturation of the larvae. Thus, a person can also be attributed to the enemies of the fish surgeon.
Population and species status
In order to characterize the species of surgeon fish as a population, the following points can be distinguished:
- Surgeon fish are distinguished by a uniform spatial distribution over their habitat
- They retain an individual territory, and also have a group space, when collected in large fish schools (sometimes mixed).
- Young animals live separately from sexually mature individuals .
- They have subordination in ranks, thanks to which they easily get along with each other and with other fish.
- The number of individuals in the population is regulated by fertility and mortality, which largely depends on the adaptive capabilities of surgeonfish.
- Surgeon fish play an important role in the biogenesis of coral reefs. By eating the upper cover of the reefs, made mainly of algae, these helper fish act as a distributor in the settling and growth of corals.
Since corals are a natural habitat for a large number of marine fish, they are extremely important for the development of their populations. But in recent years, the reefs have undergone mass extinction. Scientists have long reported that in the next 40 years, reefs may die altogether. And with them, marine animals are also under threat.
In addition, fish of surgeons and other inhabitants of reefs are actively caught by people. This has already led to a decrease in their populations by almost 10 times, which entails a violation in the biocenosis of the reef system. This means that it also leads to the death of coral reefs, and marine animals, and surgeon fish, in particular.
Although the surgeon fish is not yet listed in the Red Book, it has rather high risks soon get there.