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Pam Chin, 2002
Cichlid Room Companion
Articles

Mouthbrooders Stripping vs. Holding

Par & Marcelo Casacuberta, 2000. image
Publié

Classement: Maintenance captive.

One of the great joys of fish keeping is being able to successfully breed and raise up the fry of your favorite fish. However, there is a certain amount of responsibility that you incur when trying to do this. You must consider the political, moral, ethical, and biological issues, as well as the more practical, effective and inventive ways.

Thus is the case with stripping, which is the removal of eggs or fry from the mouth, of brooding females before the incubating period has finished. Most of the mouthbrooders kept in our tanks are Cichlids from Lake Malawi, Tanganyika, and Victoria. There are also Cichlid mouth brooders from the rivers in Africa, and South America who also use this method. This technique, called stripping, can help us successfully breed all these species. But, does that mean we should do it? Are we abusing it?

Once we have a case in which stripping must be performed, there are some rules to follow in order to make it safer for you and your fish. Before handling the female, be sure to wet your hands in the tank, dry fingers can damage the protective mucus or even tear scales apart. Hold her body firmly but without pressing it, and use a wide bowl to keep the head under the water while you gently open her mouth with a paper clip, Q-tip, etc., and allow the eggs to fall to the bottom. In my few experiences, I hardly got any viable fry when stripped the next day after spawning. I prefer to wait at least five days, after the eggs have hatched and then place them inside my filter. I am a big fan of using the "hang on" type of filter that returns the water to the tank as a small waterfall. I place the eggs in a net (to avoid the waterfall dragging them) so they receive a continuous flow of clear oxygenated water.

Any white, fungused eggs must be quickly removed away from the viable ones. Survival rates are over 90%. Of course breeders will develop techniques and skills that fit their set up and the species they keep, but that is another story.

This behavior of mouth brooding is a unique breeding strategy, found in many other fishes, such as catfish, Anabantoids and arowanas to name just a few. Even some salt water fishes use this technique. Many researchers believe that mouth brooding means an advance in the evolution of reproductive methods, since it provides extended protection to the offspring. When the young ones are finally released, they are larger than the average substrate fry and have a much higher chance of survival.

It is the mouth brooding Cichlids from the Rift Lakes where stripping females is widely practiced. When we discover one of our females is holding a mouthful of eggs or fry, there are many different ways to insure the life of the embryos. Whether we take the female to a maternity tank, isolate her from the rest of the fish with a glass-divider, or wait for a few days and strip her.

In this day and age most hobbyists community tanks are actually biotope's of where their fish originated. They carefully match tank mates, that come from the same localities, simulate the natural water conditions, provide the same type rock work and substrate, that is found naturally. In short, they like to duplicate Lake Malawi in the middle of their living rooms, hoping that nature will take its course, in the most natural way. But is this really natural? Who are we trying to kid? When you take a fish out of a Lake that is 350 miles long, 50 miles wide and put it in a 60-gallon tank, can you call that natural?

In the wild, a brooding female can swim away from the spawning site and look for shelter, in our tanks this is just impossible. So, if we have produced unnatural conditions, maybe we should consider the unnatural solutions. Stripping, which is obviously unnatural, has become a practical and accepted way to aid hobbyists in the rearing of fry. But is it right?

Perhaps we need to evaluate what our goals as hobbyists are. Are we interested in raising huge amounts of fry, in a massive farm-like production? Or should our priority be recreating the conditions that allow our fishes follow their natural instincts so we can enjoy watching them behave as natural as possible?

It might be more work, using tank dividers or setting up maternity aquariums, but some find it is worth the extra effort. Often stripping is attempted after the sad experience of a novice mother eating her own eggs. Maybe the best choice in this case would be waiting until she learns to do it, all the way, by herself. It is easy to understand the anxiety of a hobbyist waiting to get that desired first spawn, but patience should be an important quality for all of us attempting to keep and breed fish.

Stripping is also performed to shorten the fasting period that many mouth brooders practice while holding, and to get the fish back in breeding condition sooner. There are some species that eat when holding, but the majority takes no food at all while incubating. They are adapted to do so and can handle it without suffering or physical damage. We must be aware that mouth brooding females have been designed for this abstinence, and have evolved for thousands years to go through this period without food. A couple of weeks of nutritious meals after they release will return them back into top condition.

Most think the stripping controversy is more about the stress on the female. Whatever method you use, you can cause the female to stress out and spit out. Once out of the tank, and she hasn't spit yet... Which is more stressful? Holding for 21 - 28 days with no food intake or having your mouth pried open with a paper clip and shaken around in a tub of water for 5 minutes. Bottom line: Mouth brooding is a stressful time. Do they remember this adventure? It is unlikely; a frontosa can't even remember the rock in the middle of the tank. So, it is doubtful that the stress of stripping is going to have a lasting effect.

A good trick to reduce the stress in chasing your females to death is turn off the aquarium light during the day, when you come home in the night, and turn on the light the fish will be sleepy and easy to catch. (At least for the first three or four minutes) Having the female in a jar with water from her tank, I turn the lights off again, and using a flashlight, take her to the maternity tank. She won't notice what has really happened until next morning and incubation can go on normally. Using this simple way, I have never had a female spitting or swallowing the eggs.

Stress is not the only issue; there are others that effect stripping in the maternal behavior of these mouth brooders. You can find written accounts of hobbyist's that suspect there can be some serious side effects. Like the experiences of a breeder who used to strip his females after ten days of incubating the fry. Once the females that were born in such a way reached maturity, they to hold their own fry for only ten days, and if not stripped before then, they ate them. Experiencing the whole brooding process, including being released and reentering in the maternal pouch until becoming fully independent, could be the way the fish acquire the patterns to follow in their reproductive life.

Yet many experienced breeders have observed that stripping has no bearing on whether or not female's hold. After working with several successive generations, they have found that stripping doesn't seem to affect their ability to hold at all. It appears that holding is an instinct that is imprinted in the fry and has nothing to do with learning it's from a parent(s).

If you have females that don't hold, you can obtain viable fry, by stripping. When a mouth brooder keeps swallowing, you have nothing to loose by stripping and hatching out the fry yourself. This in turns allows hobbyists to get new and rarer species. Even if you loose half the fry in the tumbling process, you are still ahead. It is the hobbyist's who are keeping many of the species available today, that the fish farmers have no interest in breeding. Perhaps they are not as colorful, or they are just not in demand, but these mouth brooders would not be available if hobbyists were not artificially raising the fry.

Another interesting angle to this whole controversy is considering the holding skills as a selective factor. In the wild, only the smartest fish are able to reproduce, and raise viable fry, which suggests that these progeny would have a much better chance to reproduce also. In the aquarium, or the fish farms, where fry are routinely artificially hatched, and then raised in a controlled environment, bad parents breed as successfully as good ones. After a few generations of this, it is possible that what we are actually seeing are bad parents, in other words, fishes that would not have reproduced in the wild. And perhaps this is why we can't get them to hold in the aquarium?

Labidochromis females show no interest at all for the offspring once they are out of her mouth. It is equally amazing to see the eyes of the fry swimming inside the maternal pouch, trying to take a look at the world outside, just a couple of days before being released. These are the kind of sights we miss when we take a shortcut from what should be used more as a last resort. Stripping can make things easier for us, but we may be missing so much of what our fish have to offer us.

Like any controversial issue, stripping has supporters and fierce detractors, but we may need to be flexible here, and avoid a "black or white" kind of approach. Stripping has some high points and low points. It is an ingenious technique that enables the hobbyist to breed some challenging species, or obtain fry from inexperienced or shy females, but it can be tempting to adopt it as the standard procedure to use in our tanks. The practice of stripping fish is never going to end, and as there is no way to control it. We just shouldn't over use it to the point of forgetting what a mouth brooder really is. Fish keepers must achieve a conscious self-regulation, something that most of hobbyists develop after some years of keeping and breeding fish, and find a midway point in implementing this practice.

Citation

Chin, Pam. (avr. 02, 2001). "Mouthbrooders Stripping vs. Holding". Cichlid Room Companion. Consulté le mars 28, 2024, de: https://cichlidae.com/article.php?id=151&lang=fr.