Fish are famous for their egg-laying habit and external fertilization. But unlike most of them, few species of fishes may not lay eggs. Usually, novice aquarists are unaware of live-bearing fishes. So, they wait for their fish to lay eggs, not knowing this fact. Are you also waiting for your swordtail fish to lay eggs?
If you are, I am sorry, my friend, for you will have to wait forever because swordtail fish do not lay eggs. Yes, you read that right. Swordtail fish are a type of livebearer that gives birth to live babies. They mate internally, and females carry the fry inside their bodies until they are born.
If you are a beginner and do not know much about live-bearing fishes like Swordtails, then this article is for you, my friend. After a lot of research on this topic, I have incorporated some facts and findings here. I hope you will find it helpful.
What Are Livebearers?
Livebearers might be an alien term if you are new to fish keeping. But, if you have been keeping fish like Swordtails for quite a while then, I think you might know it very well.
Actually, a livebearer is any freshwater or marine fish that gives birth to living offspring. This excludes egg layers, which lay eggs and are not alive when they hatch.
Livebearers are also called ovoviviparous or viviparous fish because they produce their offspring inside eggs.
The young will hatch from the egg within a few days to weeks inside their mother’s body and continue development in the safety of their mother. Isn’t it amazing! Don’t you think these fishes are quite similar to us humans? Just like us, the mothers carry their babies in them and give birth directly.
Some live-bearing species include guppies, platies, mollies, and swordtails.
Do Swordtail Fish Lay Eggs?
This is a very famous question among aquarists and fish-keeping enthusiasts. Unfortunately, the answer to this question is NO. Swordtail fish is a live-bearing species that do not lay eggs. Instead, fry (baby) swordtails are produced within the female’s body without laying eggs beforehand.
The eggs of Swordtail fertilize internally and fry also develop inside the female’s body. After their development is complete, labor will begin, and the fry will be released from her body.
The whole process of pregnancy happens in the Swordtail’s body. It is the same as humans. But, swordtail fish get food from the yolk, and we get it from the placenta. Besides this, the other difference between humans and swordtails giving birth is the time frame. Unlike humans, the gestational period of Swordtail is very short, at about a month.
To sum up, the most usual reproduction behavior in swordtail fish is to give birth to fry directly. However, there do are times when these fish might lay eggs. Do you know when?
The only time when your swordtail fish will lay eggs are:
- If the fry doesn’t form properly
- If the eggs are unfertilized inside her body
A fry will not be born in such cases, so it’s the best advice to remove such eggs from the tank.
How Do Swordtail Fish Reproduce?
Mating is the most natural behavior among living things. Therefore, you do not need to put a lot of effort into making your swordtail fish mate. In fact, it is the easiest thing you can do. Of course, it would be best to keep the male and female Swordtails in the appropriate ratio. I personally prefer three females and one male. But it is up to you. Along with this, you must also maintain a suitable breeding environment in the tank. For this, you need to check the water parameters regularly and manage them.
Usually, the reproduction of Swordtail starts once they mature fully. And it takes these fish about three months to start producing their offspring. So, when your Swordtail reaches four months, they are ready for reproduction.
As mentioned earlier, the breeding process of a swordtail is easy. And, you can easily breed Swordtails at home too. But at first, the male Swordtail will relentlessly chase the female swordtails to deposit his sperm through the gonopodium into the female anal fin.
When the sperm meets the eggs, they fertilize. After fertilization, the fry develops inside your pregnant Swordtail. They might get a few days to develop fully. So, this period is quite crucial for getting healthy and more fry. Therefore, you should take proper care of your pregnant swordtail fish. It is a must to check the water parameters of the breeding tank during this period so that she doesn’t go through complicated labor.
In general, the gestation period of Swordtail lasts for 28 days. And after 28 days, your female Swordtail will undergo labor and bear 50-100 fry. But the timeframe and number of fry fluctuate in each pregnancy. It all depends on the quality of sperm and the breeding environment.
How Often Does Swordtail Fish Give Birth?
Swordtail fish are prolific breeders. This means that if you keep the proper ratio of males and females in your tank, you will get fry every other month!
The swordtail fish is pregnant for 28 days so that she can get pregnant every month. You need to take care of the pregnant swordtail fish because she has all her eggs in her belly. Once the swordtail fish has dropped all of her fry, she can be pregnant again!
Female swordtail fish can store sperm in their belly and give birth every other month. Even if you keep all female swordtails in your tank, they may get pregnant periodically as the male stored sperm can sometimes fertilize eggs from another period.
Swordtail Fish Fry
After 28 days of pregnancy, swordtails will drop the fry. On average, a swordtail will give birth to about 50-100 fry at a time. But, this usually depends on each fish. Mine, however, normally ends up giving around 70-80 fry in each pregnancy.
Taking care of these tiny creatures once your baby swordtails are born is very important. Moreover, if your Swordtail shares the tank with other fishes, it is crucial to take care of the fry. Swordtail fry is about 0.25 inches long, so they are vulnerable. The bigger fishes might even eat the babies of Swordtail. Hence you should separate the Swordtail fry from the main tank and take proper care of them until they are big enough.
Generally, Swordtail fry care includes:
- Providing hiding spots
- Proper feeding
- Separating from parents
How To Control Swordtail Fish Population?
As mentioned above, swordtail fish are efficient breeders. So, you might sometimes receive more fry from your Swordtail than expected. Taking care of all these baby Swordtails is undoubtedly fun. But, it is a little hectic and expensive. Especially if you are a job to do and have a limited budget, then looking after many fry may be messy. Thus, if you are not looking into breeding them, here is some advice:
Separate Males And Females
The gender of your Swordtail is very easy to separate. You can just look at your fish’s tail and Identify a male and female swordtail fish. Usually, the female Swordtail has a broader and blunt tail while the male has a sword-like tail.
Thus, if you do not want your female swordtails to have babies, then it is best to keep the females and males. In this way, your swordtails won’t have babies for months. It is one of the most used methods by many aquarists.
However, it will not be useful if your female Swordtail already has sperm stored for the future!
Keep Other Fry-Eating Fish
I know it is very heart-drenching to say that. But, if you can’t keep a lot of fish, then it is better to use a natural predator to kill them. Your tank contains predator fish that hunt down tiny fish like the swordtail fry. You can control the swordtail fish population.
Although it does appears a little cruel. But I think it would be better for the health of living fishes as they will get proper food and space to live. More to this, survival of the fittest is very common in the wild. So, it is no harm.
After getting familiar with moth of the questions related to swordtails and their reproduction, I bet you still have some queries in your mind. Therefore, here I am with a few of the frequently asked questions by novice aquarists to assist you.
FAQs
How Many Babies Do Swordtails Bear?
The number of babies your Swordtail will give birth to usually depends on each individual fish. Especially, their breeding environment and quality of sperms of the males play a very important role in the number of babies burn. But in general, a healthy Swordtail can produce 50-100 at one time.
Also, note that the swordtails can be pregnant at least once a month. This means they can give birth again 4-6 weeks after the first birth. So, you can say you might receive about 600-1200 baby swordtails every year. But don’t worry, all of them do not survive!
Why Is My Swordtail Not Giving Birth?
Sometimes your Swordtails stop giving birth. Although this condition is quite unusual, it does occur at times. Thus, to facilitate birthing in your Swordtail, maintenance of thor health, tank conditions, water parameters, etc., is very important.
Although breeding swordtails do not need any external initiation, causes like stress, improper water conditions could lead to your Swordtail not giving birth. Similarly, swordtails will delay their delivery when the babies are immature.
Conclusion
All in all, I think you must be clear by now that swordtail fish do not lay eggs. Instead, they are livebearers, giving birth to live babies directly!
Swordtails are delicate during the spawning session, and you should take proper care of a pregnant swordtail. Also, take care of the fry until they are big enough.
Swordtails do not bear babies by laying eggs, so if you see any egg-laying behavior by a swordtail, that is just a defect. You need to consult with a professional as soon as you notice such things.
Best wishes for breeding your Swordtail. Happy Fish Keeping!
