The aquatic world is undoubtedly very interesting, so you will surely find the fish and their reproduction very pleasant. However, the reproduction of fish can become somewhat complex; therefore, you must make sure to inform yourself a lot before starting to get down to work.
If you are here because you want to start your own aquarium, you should know that you are not the only one. Fish farming or aquaculture is a practice that, in addition to being important, is constantly growing. Don’t be afraid to explore this trail, it will surely make you very happy.
And, since you learn something new every day, today you will learn how fish reproduce. Also how to take the first steps in this new direction, as well as other interesting things. Make yourself comfortable, and let’s begin!
Sexual characteristics of fish
Like humans, fish are dioeciously animals, which mean that they are divided into males and females. Despite this, there are cases in which after reproduction, one of the participants changes sex; this is known as successive hermaphroditism, where either a female can become a male, or vice versa. Although they are almost always oviparous, they can also be viviparous or ovoviviparous.
Also, most species do not have any type of ovulatory organ. Thanks to this, reproduction in these cases is an external fertilization. This, of course, can vary. Keep reading to find out how the process of fish reproduction occurs and how it can vary depending on the species.
Instructions for reproducing fish
As we told you above, there are three fundamental types of reproduction in fish: oviparous, viviparous and ovoviviparous. But even though they are different processes, they follow a few general rules.
The reproduction of fish is subject to certain time intervals that are called breeding seasons. These can happen one or more times a month, every year, etc., depending on the species.
Firstly, there is a vast variety of external factors that affect the reproductive process. Among these are the temperature, the oxygen level of the water, the light that comes from outside, among others. Incubation time depends on both temperature and species; each one has a certain period of incubation, but a higher temperature will make the egg need more time to develop.
The oxygen in the water, on the other hand, is a key factor for the well-being of hatching eggs. If the oxygen level drops, the eggs are in danger of not hatching, and development slows down. As a result of this, some species have perfected techniques to protect their eggs from oxygen problems; they build (almost always the male) bubble nests, like the Beta Fish or the Gourami’s.
It is common to see a series of migratory processes between the species when their breeding season approaches. Thus, they synchronize their reproduction and go to deeper places to be able to spend their time comfortably. Species such as snapper or catfish can travel from a few meters to thousands of kilometers. Likewise, they can travel in a group, as a couple, or alone until they find their perfect match.
Cases have been seen in which in the midst of these migrations the species has been threatened by fishermen. This puts the conservation of some of the fish families and their persistence in great danger.
Once the reproductive process is finished, they return to the safety of their reef or natural place, to wait for the next breeding season and start the whole pattern again.
Now, let’s talk about fish with oviparous reproduction. In this type of reproduction, the female lays a number of eggs. Subsequently, these eggs are fertilized by the male, whose sperm is dispersed in the water. If the fish is a demurral spawned, the eggs will stick to the bottom, as these are denser than water. Otherwise, pelagic spawning fish will let their eggs disperse based on the sea current.
It is common to see among demurral spanners a much more complete and elongated embryonic development. This is because their eggs are usually larger and have more nutritional content than those of pelagic spanners. An example of this type of fish can be the Damsel fish, of the Pomacentridae family.
Some of these mothers continue to raise their young until they teach them to swim. Others, on the contrary, abandon them from the moment of fertilization or after hatching.
The reproduction of ovoviviparous fish, on the other hand, does have anovulatory organ, that of the male, called a monopodium; with this organ, the male introduces the sperm into the female’s ovarian cavity. Fertilization is internal and the female carries the eggs in her womb throughout development, until hatching.
Although fertilization is internal, the nutrition of the embryo depends on the yolk of the egg, not the mother. Even so, the mother keeps the sperm and therefore can produce several more batches without the presence of the father. The Poecilidae and Scorpaenidae families have representatives of this type of reproduction in both salt and fresh water.
Finally, there is the reproduction of viviparous fish. This is also a process of internal fertilization; the male introduces the sperm to the female through modified fins in the form of anovulatory organ.
In this type of reproduction, females give birth to their young, which are actually born able to swim and fully formed. In addition, a characteristic of this reproductive strategy is the great mother-embryo dependency that exists. The embryo is totally dependent on its mother for nutrition, excretion, and respiration.
If you are wondering about its representation, more than 13 families of fish use this type of reproduction. This translates to more than 520 species, among which the shark and the ray stand out. We have all wondered how sharks are born, well, this is the answer.
What do you need for fish to reproduce?
- Know the breeding season according to the species.
- Adequate water temperature and acidity.
- Healthy food.
- Constant surveillance.
- A fish farm.
Tips for fish reproduction
Although breeding fish in captivity can be complex, you should not be scared. It’s all about practicing, getting informed and getting the hang of it, and you’ll see that you’ll soon be an expert. Here are some tips to make your path in aquaculture much easier. Breeding fish in captivity has never been easier.
- Find out about the type of fish you want to breed. You must bear in mind that each type of fish is different and has varied attitudes and courtships.
- The Beta fish, for example, is a very commercial fish and that is why you may want to start with it. However, this is an extremely aggressive fish.
- Therefore, the best way to reproduce it is to keep the male alone in a pool and put the female in an isolated container; just to serve as stimulation. This will cause the male to form a foam nest, the female will release her eggs, and you should remove her immediately.
- Once the larvae hatch, you must take them to their own aquarium, or the parent could eat them.
- Other less aggressive fish will present variations in the process. This is where the importance lies that you inform yourself very well about the species you want to reproduce.
- Choose easy species at first. Some species of fish are easier to breed than others. If you opt for them, you can buy groups of 6 or 8 fish to reproduce in groups. Your chances of success will increase this way.
- Find out the diet of both the fish and the fry. Although it sounds obvious, it is worth saying: not all fish eat the same thing. Some need infusoria cultures; others need brine shrimp (newly hatched shrimp). There is a much longer list of options than you think. Make sure you know their diet well so you don’t risk them dying.
- Just because you feed them well doesn’t mean you overfeed them. Fingerlings, for example, need constant food, but in small amounts. Remember: overfeeding is just as bad as under nutrition.
- Get advice about the reproductive habits of your fish. Above we discussed the different ways in which a fish can reproduce. You now know that there are three types of reproductive patterns, find out which group your fish belong to. Do it from the beginning! This way you avoid accidents, or possible cannibalistic scenarios!
- As we told you before, there are fish that must be separated immediately after the mating process. In other cases, it is extremely important that they stay together, even after the fry hatch. There are even cases where only the father should stay with them, or the mother. You should not overlook those kinds of details.
- Generate the necessary conditions. You cannot reproduce and raise fish in glass cups and feeding them dry bread. Take this seriously and find out about the tanks you should buy, the chemicals needed for cleaning, etc. Remember that above we mentioned the impact that temperature and oxygen have on incubation; thing you should keep in mind.
- As in any science, the ideal is that you always stay informed, and your success will be inevitable. Above all, enjoy what you do and find the fun in it.
The fish are extremely interesting. Did you know that they were the first vertebrates to appear on earth? That’s one of the many reasons why they are super cool animals, so give them all the attention they deserve!
