IN THE WILD,
the presence of sometimes more than 70 different species at a single locality might make it difficult for a female to find her correct mate. To counter this problem, it is thought that most Malawian rock-dwelling species use colour and colour patterns for identification, while many sand-dwelling species identify themselves by the type of spawning site they construct on the sand.
These sandcastles are often called nests, but they are not true nests in the sense that this is a place where youngsters are raised. Instead they are often elaborate display sites, built for the express purpose of attracting a mate , somewhat like those built by bower birds, and are thus also referred to as ‘bowers’ in the aquarium world. This does not mean they are not important — far from it! These elaborate structures convey vital species-specific information, as well as information about the quality of the male that built the bower. Females are so highly attuned to the quality of these bowers that they can distinguish between excellent and mediocre bowers — and choose their spawning partners accordingly.
Other sand dwellers, especially inLake Tanganyika, excavate and build substrate nest and raise their fry in them. Among the builders of nests (and not bowers) their constructions nevertheless serve equally to attract mates, and many fishes put substantial effort into nest preparation, creating structures that are not only beneficial for the future offspring but also demonstrate to potential partners the skill, quality, and attention to detail of the nest constructor.
We actually know remarkably little about nest construction for many cichlids. Many nests are often difficult to detect until they are well on their way toward completion. We know that nest construction can be surprisingly rapid. Still, many aquarists only notice a nest either just before or after spawning has occurred.
The principle function of a nest is to provide a safe environment for the eggs and possibly the larvae. Achieving this usually requires modifying the existing terrain, including cleaning it, digging into it, and removing vegetation if there is any. (And there goes your plants, if you put any into your cichlid aquarium!) Almost all substrate-spawning cichlids require a solid surface on which to lay their eggs. I don’t know if they have some way of detecting solid surfaces under the sand, but inevitably the fish will somehow discover a rock in their territory — even it this means they have to dig deep. But find it they will, and that is where the eggs are laid.
Understanding why cichlids dig (though some also dig as a regular part of feeding), may ease the pain of finding your carefully arranged aquarium entirely re-landscaped. I suggest you ponder on this — if your cichlids are digging, then you haven’t provided them with enough larger solid surfaces on which to lay their eggs, and they are determined to find one, come what may. The number of eggs laid by a female on such a hard surface does not appear to be limited by its size; instead, the female lays a predetermined number of eggs and finds a surface suitably large to accommodate them. If the rock is a bit small, the female will lay the eggs very compactly. Larger surfaces allow the eggs to be more spread out. Substrate-spawning cichlids almost never lay eggs on top of each other, because to do so would not only deprive the underlying eggs of oxygen, but make cleaning them impossible.
Recent discoveries about cichlid nests suggest that even more complex interactions than we think are occurring. Ochi and Yanagisawa (1999) described “sand-transfer” behaviour by Neolamprologus caudopunctatus, inLake Tanganyika. This fish constructs its nest among the stones in the lake, leaving a slit-like entrance to the nest chamber. The researchers found that during the period of egg and wriggler care, which lasted about 40 days, females often removed mouthfuls of sand from within the nest. This isn’t surprising, since it is regular housekeeping. But in addition, females (and rarely males) sometimes brought mouthfuls of sand from the area around the nest to the nest entrance in an apparent attempt to keep the entrance narrow. “Kribensis” are known to do this in aquariums: if the cave entrance is too wide, they may “back-fill” the gravel until the opening is just wide enough for the female to get in and out.
The researchers also found that males and females unexpectedly transferred many mouthfuls of sand around the territory, typically depositing and heaping the sand at the base of stones. The parents were not feeding and only did this before the fry became independent. The exact reason for this behavior is not known, but Ochi and Yanagisawa propose a fascinating hypothesis. Parents of this species are vigilant toward predators that lurk around the perimeter of the territory and dash in to eat the young. Common predators include Telmatochromis vittatus, a stalker, which hides under or beside stones waiting for an opportunity to arise. Could it be that the parent Neolamprologus caudopunctatus are actively filling in these potential hiding places and thereby increasing the safety of their young?
The advantages of a good nest are so great that some species take advantage of the nests of others. Lepidiolamprologus profundicola is a large piscivorous substrate-spawning cichlid, also from Lake Tanganyika. Female L. profundicola guard the nest area for about two weeks. Cyprichromis leptosoma is an open-water, maternal mouthbrooder. You might think that these two species would have little to do with each other, but Watanabe (2000) observed schools of hundreds of juvenile Cyprichromis leptosoma hovering above L. profundicola nests. This observation is unusual because L. profundicola do not guard their fry once the fry become free-swimming; the fry swim away so there is no opportunity for the C. leptosoma fry to mingle in with the L. profundicola fry as has been observed for other species. Furthermore, under other circumstances, L. profundicola preys upon C. leptosoma. However, because the female L. profundicola keeps predators far away from her nest area, and the C. leptosoma do not prey on her young, these foreign fry gain substantial protection from the defensive perimeter the female L. profundicola creates.
These two studies illustrate the importance of nests, and no doubt future work will reveal yet more intriguing ways in which cichlids nest for success.
CHOOSING A MATE AND SPAWNING
In the lake males rarely display to females of different species. Instead, it seems that males as well as females are very selective in choosing mates.
In non-territorial species, males court females upon encounter, and here in particular, species recognition by the male plays an important role. When a male thinks he has found a mate, he courts the female in the spot, simultaneously releasing a fluid that carries a species-specific scent. If the female is ready to spawn, she can thus confirm the status of her prospective partner before she embarks upon laying her eggs.
In territorial species, when the male exhibits breeding colours, he does so to demonstrate to prospective mates that he has successfully secured a spawning site. And such males are motivated to take this display to the extreme — immediately adding territorial aggression as soon as there are other reproductive con-specific males displaying nearby. This ‘mutual stimulation’ via display devours energy – assuring that only the strongest males will hold their territories and go on to mate with several females. Of course, there is another plus. A group display is very conspicuous – and therefore more likely to attract females than solo individuals would! This is called “arena breeding”
The question was whether the “egg spots” featured by males played any role in the courtship, or the spawning display. Most male Cichlids (but surprising to many, even some females) have “egg spots” on their anal fin, sometimes up to twelve in older males. Some have even more spots on the posterior tips of their dorsal fins. Several studies performed by researcher Eva Hert have shown that egg spots are not absolutely necessary for fertilization — but that females prefer and are more stimulated by males that have them. In fact, Ms. Hert determined that egg spots have the effect of priming females to produce more eggs!
In her first study, Ms. Hert showed that females of Haplochromis elegans prefer males with egg spots. She divided a group of males into two groups, the experimental males from whom she erased the anal fin spots (by touching the skin briefly with a metal that had been dipped in super-cold liquid nitrogen) and the control males whose spots remained intact. Females found the males with egg spots more attractive than those lacking them.
In a subsequent experiment, she showed that males who possessed more egg spots primed females to produce more eggs. Females placed with males showing egg spots produced twice as many eggs as females placed with males lacking them! She later did this experiment with Ast. elegans and achieved the same results. Of course, aquarium lore has it that the egg spots entices the female towards the male anal fin during the spawning dance, in the belief that these are eggs she missed picking up, and that when she tries to mouth the spots, the male knows that this is the perfect moment to release his sperm. Could this be true, or are those quivering egg spots merely a subtle form of fish porn?
Let us consider the spawning process in nature.
Two different patterns of spawning occur among theMalawihaplochrome cyclids.
In only a few species, fertilisation occurs outside the female’s mouth. In this case the male takes the lead and entices the female to the spawning site. There the female will circle the site in a few ‘dry’ runs, before eventually slowing down and depositing a few eggs. She then rapidly turns around, followed by the male fertilising the eggs, before she picks them up. They continue this dance until the female is done. If there is any threat of fish that could possibly steal and consume the eggs, the female will greatly speed up collecting her eggs.
In the more advanced species (the majority) where the eggs are fertilised inside the female’s mouth, the sequence is totally different. The male leads the female to the actual spawning site and once arrived, positions himself in front of and at right angles to her. He then lowers his body and presses his anal fin against the substrate. Quivering of the fins and especially the anal fin accompanies this posture. This entices the female to mouth his vibrating anal fin, upon which the male immediately discharges sperm, with the result that the female picks up sperm before she has even deposited a single egg. She also confirms by the male’s scent that she has indeed found her correct partner. Next the male starts circling around the female, quivering his anal fin and dragging it over the spawning site until the female finally deposits a few eggs.
Without hesitation she turns around and picks them op, while the male stays alongside to keep the still exposed eggs between them. Once done, the male repeats the quivering anal fin and sperm deposit, allowing the female to ingest the sperm. The genius of this is that the eggs are only exposed for the briefest time! The male will repeat this process dozens of times, and seems to only stop when the female loses interest. But there is a twist: After the spawning it is not only the male who goes off to new green pastures! A female too may spawn with several partners and have her brood carry the genes of them all!
Once she is done, she will find a quiet refuge, or in some cases join a school of mouth-brooding females. Interestingly enough, females will spit out eggs during their incubation period if they were not fertilized. If you watch your pregnant female closely throughout her holding period, you will notice that the load she carries in her mouth decreases after a few days. If you are a keen observer, you see it when a female discards eggs.The female will not eat during the incubation – a period that averages 21 days, but depending on temperature this may range between 18 and 24 days.
In an aquarium, things look VERY different!
We are now dealing with an artificial environment and with space constraints. Cyclids defend and protect their nests, their females and their young. Your fish will therefore tend to become very territorial and they will attack any potential enemies that venture into their “terrain”. In your aquarium this territory may be guarded even when they are not breeding, and some fish may consider the entire aquarium as their territory. It is therefore better for most cichlids to have their own breeding tank, ideally supplied with a divider, to ease separating the female from the male as soon as possible after spawning, after which he can be returned to his usual tank.
In the aquarium, you can soon tell whether a female is ‘holding’ by looking at her enlarged buccal cavity (throat area) and her mostly closed mouth.
If you observe your breeding cichlids carefully, you may notice the eggs in their mouths
The eggs hatch at around 1 week and develop into fry. At around 2 weeks, the fry have pretty much absorbed their egg sacs, which provide them with nutrition during their first stage of life. Exactly at what time the female will release the fry depends on many factors including the species type, her age, her health, her hunger, the water conditions and temperature in the tank, but in most cases, this occurs before 4 weeks have passed.
There are several methods you can employ to harvest the fry and raise the little cichlids to maturity.
With the first method, you can leave the female in the main tank and let her spit the fry out naturally. The fewer the number of other adult fish in the tank and the more shelter provided, the greater the chances of fry survival. Remember, it is up to you to provide these conditions to increase the odds for fry to survive. This method is certainly the most natural, however tends to lessen the chances for the survival of the tiny fry. It also creates a lot of stress for the female as she has to fend off males and predators keen on a little fry snack.
The second method is to remove the holding female from the main tank and transfer her to an unoccupied tank where she can release the fry when she is ready, without fear of other fish eating them. A separated female not only allows you to save the majority of the fry, but also lessens the stress on the female.
The question is when? If the female is still holding eggs, she may, when caught, spit out her eggs in the net — as she would do in nature, she will always choose her own survival above that of fry which can be replaced. If this happens to you, simply release the eggs gently into the breeding tank (which should contain sand, rocks and hides). Chances are good that as soon as she realises that there is no danger to her, she will gather them again and continue the normal incubating process. Be vey patient if this occurs. A better time may be around two and a half weeks into holding. By this time she is probably holding fry. Once in the breeding tank, and comprehending that there is no danger, the female may well spit the fry and let them roam for food, only to quickly take them back as soon as anyone approaches the tank.
She may do this for some time until she feels the fry can fend for themselves. This gives you the ideal opportunity to lightly feed the female, and perhaps even the tiny fry – although you should only feed them when their yolk-sacs have been absorbed. It is rare that a female eats her own fry, however this can occasionally happen. If she gets food, she in all likelihood will not consume her offspring. But if you feel uncertain, you may want to remove the female as soon as she has spat the fry. If you have a small recovery tank, it would be humane to let her gain some of her weight back before you return her to the main tank and its social hierarchies. This then allows you to raise the fry in their own tank without the worry of losing them to bigger fish. Be aware though that a recovering female usually does not show interest in food for about 12 hours after “releasing.”
Once the fry live separated from their mother and are mature enough to accept food, make sure you feed them often — in the beginning, light to moderate amounts, as many as six times a day. Remember, in Nature there is no breakfast, lunch and dinner. Fish eat all the time, throughout the entire day. Most fry will accept finely crushed flake food as soon as they have absorbed their egg sacks. Mix a little flake food powder with water. Then suck it into a straw, or piece of aquarium tubing. Insert the tubing into the water near the swimming cichlid fry, and release it for them to eat. Be careful of feeding live or frozen brine shrimp, although this is what many hobbyists recommend. Cichlids have an unusually long intestine, and do not cope well with whole brine shrimp, however small. If you must, shrimp pulverised in a commercial fry food would be better. Most Malawian cichlids do very well on a mainly vegetarian diet!
Fast, healthy growth in fry depends on many factors but most importantly, good water conditions, a large tank, frequent feeding, proper diet and adequate lighting. MostMalawicichlids are well capable of breeding once a month so be prepared for the next round and meanwhile enjoy your newfry!
Lest you think that I am not fully informed, there is a third method, called “stripping the fry” which is usually only used by breeders who produce cichlids with commerce in mind. Some breeders prefer to strip the eggs and incubate them in a special apparatus, called a ‘tumbler’. For that reason, I will not cover those two methods in this article.
As a final note, I should point out that successful breeding depends hugely on the health and well-being of your cichlids. You have supplied them with tunnels, caves and hides — places where your cichlids can hide and which they can call their own. This is especially important for mouth-brooders because they need extra protection from enemies while they are holding, and during this period they can get pretty thin and weak. Your water conditions must be impeccable.
So all that now remains is their diet — and diet is extremely important. As I have pointed out before, in Nature there is no breakfast, lunch and dinner. Fish hunt and graze all day long and are acutely aware of food changes that come with the change of winds and currents. In the aquarium, this is entirely different. We usually feed our fish only twice a day and of course, at times convenient to us. So, inevitably our fish have to tune in to us! While it would be infinitely better to feed smaller portions more often during the day, not many of us can and surprisingly our fish learn to survive quite well. Nevertheless we should pay greater attention to what we feed, how often and how much!
While Malawi Cichlids do well on spirulina flake, with supplements of brine shrimp, blood worms, krill, and plankton, you may want to slightly up their protein intake before breeding. Nevertheless go light on the shrimps and krill as overfeeding these can cause “Malawi Bloat.” Feeding frozen food once a week, and only what they can consume in about 30 seconds, seems enough to get Cichlids in the mood. They frequently spawn within a few hours after such a feeding. The most plausible explanation for this is that when a fish breeds, it only has a certain amount of energy to extend, before the depletion starts endangering their ability to survive and grow. This limited amount of energy will be put into the eggs. Thus by feeding your Cichlids protein-rich foods just prior to breeding, you can add to the resources they can put into making eggs. The more resources they have available, the more eggs they’ll make.
Nevertheless, never over-feed your cichlids — as this may render them unable to reproduce! If you notice that your cichlids are not breeding, and everything else is in balance, consider whether they are perhaps overfed. In this case it helps to starve your breeding pairs for about a week. You should separate males and females during this time, because Cichlids get more aggressive with hunger. You should soon notice males digging a lot, making nests, and preparing to spawn. After a day, or two of this behaviour, reintroduce the females and, voila, they should spawn.
Lastly, remember, for a female the first time mating is the biggest milestone. She might not get it in one go, and may not succeed in holding long enough, resulting in the loss of a batch. Do not fret. Most people do not know this, unless they are keen observers: Fish are keen observers — and by observing, they learn from one another! Once that young, inexperienced female has reached maturity and learned how to properly mate, she will continue to spawn with surprising regularity and success.