Shane's World Right Reproduction Right Breeding Chaca

Article © Klaus Dreymann, uploaded February 13, 2016.

At the time of writing (September 2012) I'd been keeping Chaca chaca for many years, as with many fishes we keep, sometimes you get some seemingly random inspiration from one time to another that you cannot explain exactly later. Although years ago I had a bad experience with a cave in a Chaca chaca aquarium (the catfish stopped eating well) I came up with the idea once again to place a cave on the sand of the Chaca tank. It was a spacious cave made of black clay, big enough so that two Chaca could take refuge and where the cave opening was so narrow such that it could be well defended by an individual.

A short time later, one of the three Chaca in the tank remained in the cave, but it always came to the entrance to eat and got its food there. In between, I regularly checked the cave and one day there were two of the catfish present. One was slightly inclined in the longitudinal direction towards the other and the second was breathing heavily.

The next day, there was only one Chaca in the cave again. On shining a torch into the cave I suddenly saw lots of eggs spread on the substrate at the back of the cave (see photo above). The eggs were about the size of Ancistrus eggs. This was a big surprise and I was delighted. Should I finally be lucky in breeding Chaca chaca?

On closer inspection, I saw also that the second Chaca - I supposed it was the one that produced the eggs with the one in the cave - is buried in the sand at the front of the cave entrance. I know nothing about any differing external sexual characteristics in this species. I interpreted that lying on the eggs was probably brood care. Then I had to sit back and wait while hoping that the eggs would hatch soon.

I think, as far as the diet of breeding, that is to say getting the parents into spawning conditions, there were no special foods. I do not know anything about any cannibalism of the parents towards their brood and also nothing about the actual spawning behaviour when they were both in the cave.

While performing another routine examination of the cave, I see that the eggs are still there, but the adult had now turned on to his back and I was afraid that it was dying. But then I notice that the whole rear ceiling of the cave is also covered with eggs. I left the fishes for the night with the Chaca blocking the cave from inside with his mouth open wide. Lying across the front of the cave is the likely mother of the eggs in the cave. Further back in the aquarium is Chaca chaca number three; lying on the sand.

The eggs on the cave ceiling were an elongate shape - unlike those on the cave floor - and at the bottom of the eggs on the ceiling, wagging tails are already visible. A few egg shells hang empty on the ceiling but I can't find any free swimming Chaca larvae even after a prolonged search.

When a Chaca is guarding his cave, he is probably also guarding his eggs and will do nothing that could harm them (I think this to appease myself at least). But I know nothing about the behaviour of the brood after hatching. I hope they do not flee the cave and then possibly fall prey to the third Chaca. I knew I had to transfer the third Chaca, but how many of us have a mature and sufficiently large aquarium at hand that they can count on for such a situation!

All other aquariums were stocked with fish that would instantly serve as food for a Chaca and some had catfish that would rasp on a Chaca - I know this for personal experience!

Furthermore, I have no idea how Chaca number two would react to the brood. After all, (presumably) she is permanently kept away from the cave. A small breeding tank is already set up, I probably should "simply" catch them at the exact moment of hatching. During repeated observation, I see the larvae wriggle on the cave floor. As a few days have passed, for safety's sake I have now moved Chaca number three into another aquarium.

One day later a few larvae are found on the floor of the cave. The rest remain on the cave ceiling. One larva hangs above the cave entrance. Of course, I will not let this opportunity pass me. I take it out and put it in a small glass to finally take a more accurate picture. This single fry then becomes the first in the breeding tank.

First thing early next morning I examine the cave; all the larvae are gone! One Chaca remains in the cave. In front of the cave entrance is a tightly packed collection of horn snails. They normally only act so if there is (or has been) a rich food source. I had not counted on this.

On the other hand, the second Chaca is, for the first time since laying eggs, no longer in the vicinity of the cave. At that moment I do not know how to interpret the situation properly. Then I discover five or six larvae on the cave ceiling and put them immediately into a mesh spawning box which is hanging in a well aeriated breeding tank and where no snails can get through. At least I know now that I have both sexes of Chaca and thus put the empty cave back into the aquarium, hoping that they'll spawn again soon.Two days later, the fry slowly begin to show pigmentation. The two oversized barbels left and right of the upper jaw are especially interesting.

Later that month (October) they spawn again! Both Chacas are in the cave, one of them lying with his belly to the cave roof and on the back of the other.

Meanwhile, the fry are now 1 cm long and look a little like the adult Chaca. Remnants of the yolk sac are still visible. I think the tubifex would be a promising first meal for them. The larvae swim partially through the feeding area, one I believe makes normal feeding mouth snap movements. But my first offer of a very small amount of tubifex is still ignored. I wonder if maybe the larvae respond to clearer movements - I put some daphnia into the water, which make their typical moves, but no interest from the Chaca larvae. I am not too concerned yet; their bellies are still full enough. Just to be on the safe side, I wonder to myself if I should start breeding artemia.

The next day, and in view of the appearance and size of the small Chaca, it seems to me a bit silly, but to cover me in all directions, I have started breeding Artemia. Additionally, it is calming to me to find that my Endler Guppies have bred.

I know nothing about what size the small Chaca begin hunting, but after my recent breeding successes raising different species of fish I think with Artemia, Daphnia, Tubifex, white worms and young guppies, I will be on the safe side.

When I consider how adept the adult Chaca are at eating earthworms, I imagine scaling this down to Chaca fry eating tubifex. But I become restless as I am now concerned about the development of the small Chaca. I test them carefully with a few newly hatched guppies - nothing there - no reaction. Not even when a small guppy almost collided with an Chaca snout! I took some new photos of the little ones. Meanwhile, the older animals have separated again without spawning, the remain with one in the cave, one immediately before the entrance. The adults eat an earthworm each, but nothing more.

You can see here the light outer color matching the environment: The beast in the cave is much darker than the one that is out there on the golden sand.

If my imagination is not playing tricks on me, I recognize the animal in front of the cave as spawning; where not cave animal. Until someone proves me wrong, I will therefore assign from now on in my descriptions of the sexes as follows: The Chaca chaca in the cave is the male, which also guards the brood after spawning and the other Chaca chaca is therefore the female. The male expects here to enter his cave and spawns once gravid.

Bingo! On the 25th of October, one of the newly hatched guppies is missing! I searched for a while, but there really was a guppy less than before. Also significant, is that the other guppies swim close to each other and near the surface, far away from the small Chaca. I decide on a further tubifex test and, lo and behold - it was almost heart-stopping, a Chaca moves actively to the small Tubifex ball and energetically plucks one and then another worm out of the heap until its belly is full. However, the others show no reaction in terms of starting to feed.

I was now also witness to the successful attack on a red mosquito larva. I do not need to worry about the diet of tiny Chaca anymore: Everything that moves and could fit in their mouths is bravely attacked and eaten by the little ones. They are just like their parents in miniature.

The hanging breeder net in which resides the brood, has a fine mesh size that allows only Tubifex and very slim bloodworms to drill into the bottom and thus slowly escape into the surrounding tank. Today I offer another tangle of tubifex and a few worms make for a quick escape but without having expected the Chacas! A worm snapped with a final jump-attack and then, because he had already partially forced through the mesh floor, pulled with vigorous force. The tiny Chaca then began crocodile-like rotation around its own longitudinal axis from the bottom and then - as I recall seeing various lizards do - threw the worm in the "air" and collected with its mouth again.

Meanwhile, the parents pass the time in their cave so entwined in a ying and yang fashion or by each other's side, idly lying around on the cave floor. Their current behaviour is still quite unclear to me. Sometimes they both lie side by side, sometimes on another, sometimes back to back. It's now been seven days like this. They don't seem to tend to the eggs much.

After just four weeks, the juvenile Chaca are now almost 3 cm long. They are well fed and very nimble. They deftly escape when once again a big spoon from above comes down to lift them for a photo shoot. The first one lay on its back in the petri dish until the annoying procedure was over. Despite very light background the small Chacas are still very dark after four weeks.

After seven weeks they begin to lighten in colour and have reached around 4cm. I still keep them segregated because I am afraid that otherwise I can no longer effectively monitor their food intake.

Now they're a three months old, during the water change, I release all three babies out into the open. They are still in the breeding tank, no longer in the nursery, but in the tank proper and they experience the sandy substrate for the first time. They take exactly one and a half minutes until the first has dug headlong into the sand - just like the parents do. The control of their food intake becomes more difficult, but I have also put the guppy junveiles into the tank. Over the next week, two of them are always visible on the sand, one not. The guppies have reduced from 15 to two in number. Even a single juvenile Neon tetra Paracheirodon simulans was obviously eaten in what is quite an achievement given the size of the mouth Chacas. For those interested in water values in the tank was kept as 24°C - pH 7.5 to 900 µS

On closer examination of the skin of the Chaca I discover several nearly circular markings and openings on the skin of the front body, which I previously had probably always overlooked - even in adults. Since Chaca are always very focused and effectively react when prey approaches the muzzle from behind and over the fish's body, these points may well have sensory function, but that should be the subject of thorough investigations.

I think, despite the mysterious disappearance of much of the brood after they became free-swimming, it has become a more successful breeding of Chaca chaca. I will continue to monitor carefully to find out how the sexes are assigned correctly and will, of course, aim to achieve a complete spawning to experience the sight of a hundred or more of the most beloved mini-monster.


There is further information on this species on the Cat-eLog page.

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