Fish are the most diverse aquatic vertebrates in the world and can be found in almost any body of water. There are a large number of orders and families, each with its own unique characteristics that differentiate it from the others. In turn, there are differences in terms of their ecological requirements and lifestyle, and linked to this are their feeding methods.
We can find endless ways of feeding and, furthermore, the foods that each group consumes are very varied, so much so that there are fish that only feed on the meat of other fish and other animals (i.e. carnivorous fish), others are filter feeders and some even only feed on algae or vegetables. It is this last case that we will see on this occasion, since we will talk about herbivorous fish. Continue reading this article on our site and we will tell you all about the herbivorous fish, types, names and examples, as well as other typical characteristics of this group of fish.
Characteristics of herbivorous fish
As we mentioned earlier, herbivorous fish are those that base their diet on consuming only plant-based food. In general, they inhabit warm waters in tropical zones, and are more abundant than other groups of fish, although they are also present in temperate zones. They are authentic collaborators of the ecological balance of the seas, because many algae or aquatic plants depend on them to remain within their limits. Likewise, this favors the development of corals that have slower growth, so a change in the abundance of any of the species of these fish could lead to drastic transformations in the reefs, such as being covered by algae in a short time..
From an anatomical point of view, they have certain characteristics that differentiate them from other fish. Their oral cavity is generally shorter and blunt in shape, in addition, most have teeth grouped in rows that are capable of crushing or scraping food, even digging on the floor. Parrotfish, for example, have a beak, which are teeth joined or fused in the mouth, and that allows them to scrape their food. In addition, their digestive system differs from that of the other groups, which we will see later.
Some species could be said to be grazers, that is, they graze the algae (just like a cow would in a pasture), and spend much of their time feeding, since they need to consume a high percentage of algae or vascular plants to cover their nutritional needs and obtain sufficient energy.
What do herbivorous fish eat?
This group of fish bases its diet almost exclusively on vegetable matter, either feeding on algae of different sizes or on aquatic vascular plants, this will depend on the depth in which they live.
As we mentioned, these animals spend more than 90% of their time looking for food and feeding themselves, since this type of food provides them with a lot of vegetable protein and fiber, but the amounts are smaller, which is why your stomach is working at all times to be able to digest this food. In general, these fish supplement their diet with other types of food, which may be of animal origin, since it is difficult to speak of strict herbivorous fish, however, some species do consume exclusively algae or plants. We will see examples of them later.
Digestive system of herbivorous fish
All fish share general anatomical characteristics, however, each group has differences related to their lifestyle and ecological requirements. In the case of herbivorous fish, the stomach is a muscular structure, which is called the gizzard, and which allows it to grind and digest fibers of plant origin. On the other hand, its intestine is longer than the rest of the groups of fish, and longer than the fish itself, being4 to 5 times longer than this one, which allows a good and slower absorption of nutrients.
Names and examples of herbivorous fish
Blue Parrotfish (Scarus coeruleus)
Belonging to the family Scaridae, this parrotfish is distributed in tropical and subtropical zones to the west of the Atlantic Ocean and the Caribbean Sea, where inhabits shallow waters with sandy bottoms and coral reefs. It reaches a length of 30 to 80 cm and is characterized by being intense blue in color and for having a “beak” in its mouth, formed by the jaws, as well as a conspicuous hump on the head that can be present in both males and females.
Their beak allows them to feed on the algae available on the coral reefs, thus helping to maintain their populations and thus prevent them from covering the corals. In addition, they have pharyngeal teeth, that is, in the throat, which allow them to gnaw the coral and rocks and be able to crush them, thus forming new sand that is expelled by the fish. In this way, blue parrotfish play a very important role in the formation of sandbanks and small islands
White Blackjack (Kyphosus sectatrix)
From the family Kyphosida, the white chop is found in tropical and subtropical coastal waters around the world. It can be seen in waves and shallow areas with algae reefs and rocky and sandy substrates. It is a fish that measures from 50 to 70 cm approximately and has a shape that makes it look like it has a long snout, since its head tilts towards forward from the eyes.
Its color varies from greenish tones to gray on the ventral part, with individuals that curiously can be yellow with spots. It is a fish that forms schools and it is common to observe them together with other species of fish. They feed mainly on brown algae, but if the situation requires it, they can also consume molluscs and debrisof aquatic mammals, such as dolphins.
Salpa (Sarpa salpa)
Salpa, also known as salema, belongs to the Sparidae family and is present in the Mediterranean Sea, in the North Atlantic Ocean, in the Bay of Biscay, in the Mozambique Channel, in the Canary Islands, in Madeira and in the Azores Islands. In general they live at a depth of 15 or 20 meters
It has an oval and compressed body about 50 cm long, grayish in color with characteristics orange stripes on the sides of the body, and with the presence of a single dorsal fin It is a gregarious species that always swims in company and, although adults are herbivores, juveniles are omnivores. They always swim in company and consume various types of algae, in particular they feed on toxic exotic species, which has led to their consumption causing he alth problems in humans. As they are the few species of herbivorous fish present in the Mediterranean, they play an important role in maintaining their entire ecosystem.
Surgeonfish (Paracanthurus hepatus)
Also known as the royal surgeonfish, this fish belongs to the Acanthuridae family and has a fairly wide distribution, as it can be found in various seas around the world, such as Australia, Asia and Africa, among othersIt inhabits areas with coral reefs, in depths of up to more than 30 meters, using some corals as a refuge from predators.
It is a species of about 30 cm in length and very striking, with a bright blue color throughout its body, two black stripes on the sides and with the pectoral and caudal fins with yellow details. Due to their colors and design, they are frequently captured for aquarium hobby. Juveniles, in general, swim in groups and feed exclusively on plankton Adults are not exclusive herbivores, but base their diet mainly onmacroalgae
Spotted Parrot or Shiny Parrot (Sparisoma aurofrenatum)
This fish of the Scaridae family is endemic to the western Atlantic Ocean, where it is found from Bermuda to Brazil, including the Caribbean. It can live up to more than 70 meters deep, but in general it is found in areas of corals, algae and marine plants, on which it feeds. It is about 30 cm long and has a reddish-bluish color throughout its body, the fins are redand has a characteristic black spot behind the operculum, although some individuals may not. The juveniles, on the other hand, are more brownish brown in color and have a reddish belly.
In general, it moves in small groups and during the breeding season it moves to the bottoms with grasses, where it later breeds, being a protogynous hermaphrodite species, that is, it possesses both sexes until the reproductive season, when it becomes a male. Here we leave you more Examples of hermaphrodite animals and how they reproduce.
Barber or brown surgeon fish (Acanthurus bahianus)
The barber belongs to the Acanthuridae family and is found in tropical zones of the western Atlantic Ocean, where it inhabits areas of coral reefs with sandy bottoms and presence of algae meadows, being one of the most common herbivorous fish species in its distribution area. It is a fish whose body is oval in shape and can reach more than 30 cm in length. It has a purple-brown color with more yellow fins, a slightly elongated snout and a small mouth, although protractile.
They form small territorial groups, even with other species, such as the blue barber (Acanthurus coeruleus), with whom they patrol their habitat and also they feed, and can be found up to almost 40 meters deep, although they prefer shallower areas to feed.
Chinese Carp (Ctenopharyngodon idellus)
Also called grass carp, it is a fish of the Cyprinidae family native to Asia that is present in Siberia and China, where it inhabits slow-water riversand with abundant aquatic vegetation, which can be found up to 30 meters deep. It is a very tolerant species to water salinity and oxygen deficiency. Its length can reach more than a meter, and its body is greenish-brown
This is a species that has been introduced to the United States and Europe to control the growth of aquatic plants. In addition, it is one of the most used fish in aquaculture, since it has a very fast growth. Grass carp feed primarily on algae and aquatic plants, but may supplement their diet by consuming detritus or insects.
Silver carp (Hypophthalmichthys molitrix)
This species of fish belongs to the Cyprinidae family and is native to East Asia. It is distributed throughout China and Siberia, as well as in other countries where it was introduced. It lives in temperate and subtropical zones, in slow-moving rivers and lakes, where it is common to see them very close to the surface. Silver carp are about a meter long and have a characteristic silver-green color, hence their name. Unlike other species of carp, this fish has eyes located more ventrally.
Their introduction in other countries is due to the fact that they are used to control populations of filamentous algae and certain species of aquatic plants, but like the Chinese carp, their populations have caused ecological problems in some areas, since they consume all kinds of plants, not only those that are intended to be controlled, thus becoming an invasive species.
Electric blue Johanni (Melanochromis johanni)
Also called the Johanni cichlid, this fish is endemic to Lake Malawi, in East Africa, where it inhabits rocky areas up to 15 meters deep. Its body is elongated and measures about 10 cm long, the female being smaller and yellow in color or with dark bands on the sides. The male, meanwhile, has a striking blue color all over his body, with white or lighter bands on the sides.
The blue Johanni is a calm and gregarious species, although it is territorial with males of the same species or of the same gender, since they have similar colors and can be confused with those of the same species. In general, they consume algae attached to rocks and plankton, and for this reason it is common to observe them on the rocky bottoms
Nile tilapia (Oreochromis niloticus)
From the Cichlidae family, the Nile tilapia, as its name suggests, is native to the Nile River, although it is present in regions of the Middle East, where it inhabits waters calm and shallow Its body is oval and laterally compressed, it measures about 60 cm in length and its color is greyish, presenting the breeding males reddish tones in the caudal fin.
It is a species that has currently been introduced in other regions for consumption, since it has a wide tolerance to the conditions environmental and food. In addition, it is easy to reproduce and has a great resistance to diseases. It feeds mainly on aquatic plants, but can also consume small invertebrates and filter suspended particles.
Other herbivorous fish
In addition to those mentioned above, these other herbivorous fish also stand out:
- Yellow Blackjack (Kyphosus vaigiensis)
- Angelfish (Pterophyllum scalare)
- Rock Sleeper (Aidablennius sphynx)
- Princess parrot (Scarus taeniopterus)
- Butterfish (Odax pullus)
- Bream (Kyphosus sydneyanus)
- Foxface Rabbitfish (Siganus vulpinus)
- Marbled Siganus (Siganus rivulatus)
- Gardí (Scardinius erythrophthalmus)
- Rutile (Rutilus rutilus)
- Borrachilla (Scartichthys viridis)
- Short-nosed unicornfish (Naso unicornis)
- Spotted Unicornfish (Naso brevirostris)
- Dark angelfish (Centropyge multispinis)
- Butterfly fish (Chaetodon kleinii)
- Blue-eyed surgeonfish (Ctenochaetus binotatus)
