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The Peacocks of Lake Malawi

by Marc Elieson

The so-called Peacock cichlids of Lake Malawi have achieved sustained popularity among aquarium hobbyists for more than three decades. The Malawi Peacocks possess several characteristics that have kept them in perpetual demand. First and foremost, Peacock
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males are some of the most spectacularly adorned of all cichlids. Just like their avian namesake, Peacock males sport dazzling iridescent colors while females and juveniles remain quite plain. As juvenile males grow, they undergo a dramatic transformation from drab silver or grayish-brown into brilliant blue, tawny gold, bright yellow, blood red, and rusty orange. Once mature, their colors are omnipresent, unlike other spectacularly adorned cichlids whose color is principally mood-dependent. Males are almost always on display, sticking their fins out, trying to catch the eye of a would-be admirer. In contrast, Mbuna and most Haplochromines only do this when exerting aggression or attempting to spawn.

Another factor contributing to their popularity is their relative peacefulness with other fish, making them suitable candidates for a community-type aquarium provided the other tankmates are selected appropriately (more below). Peacocks also breed readily and are relatively undemanding aquarium residents. These attributes make Peacocks appealing to both the beginner and advanced hobbyist.

The Peacocks of Lake Malawi consist only of those fishes from the genus Aulonocara. Members of this genus are characterized by a remarkably enlarged lateral line system. The lateral line, or lateralis, is a line of perforated scales along the flanks of a fish which lead to a pressure-sensitive nervous system. Specialized cells within the lateralis, called neuromasts, enable a fish to detect vibrations and electrical impulses in the surrounding water. The lateralis is thus essential in allowing a fish to detect potential predators as well as prey (Loiselle 1985). Peacocks are particularly pressure sensitive due to an enlargement of the facial pores and an extension of the lateral line onto the jaw. The squamation
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across the bones of the face is left nearly devoid of scales, making this extension and enlargement of the cephalic lateralis clearly visible as pits and grooves (Konings 2001). “These characteristic openings are easy to recognize if one observes Aulonocara spp. outside the water in slanted light.” (Spreinat 1995). The pores on the suborbital bones of the head are so dramatically enlarged they resemble the holes of a flute. In fact, when Regan erected the genus Aulonocara in 1921, he chose this name based upon this fascinating and unique characteristic. Aulonocara is derived from the Greek aulos, which means “pipe” and kara, meaning “head” (Eccles 1989).

Living in deep and dark water, the Peacocks have developed and rely on their enhanced lateralis sense to hunt for food. Aulonocara are benthic insectivores and are therefore almost always found along the sandy bottom of the lake. They hunt sand-dwelling invertebrates with the aid of these enlarged pressure sensitive tubes in the flesh of their jaws. They hover motionless above the sand by just a few millimeters. With the very sensitive and enlarged sensory pores on the lower part of their head they are able to detect the micro-movements of tiny invertebrates in the sand. They hover motionless until such a prey's movements are detected. Such a detection is followed by an instantaneous bite into the sand. Sand is then strained for food by shooting it out the fish's gills while retaining the acquired treat (Konings 1995).

This hunting technique has not been documented in the aquarium, most likely due to the absolute lack of insect larvae and other small crustaceans living in the aquarium substrate. They often sift through the sand after
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each feeding, probably looking for any small particles of food that were missed. In the aquarium, Peacocks readily adapt to and accept almost any commercially prepared food. While they require animal protein in their diet, it is wise to also provide some Spirulina to keep their blue color looking its best. Similarly, a fish food with krill will maximize reds and oranges. All reputable cichlid foods contain an adequate amount of yellow pigment so as not to be a conscious concern in the selection of food. Frozen and live foods can be fed periodically but these are not essential. A quality fish food with high levels of protein will be sufficient. If used, frozen and live foods should only be used as supplements to a diet of flake and/or pellet foods. Also be aware that larger adults will need more than just flake food to keep them in optimal breeding condition. It is best to feed Peacocks only one to two times a day, and never more than they can consume in two minutes. Unlike Mbuna, whose aggression necessitates feeding several times a day, Peacocks have a mild temperament and are very undemanding. Consequently, their feeding regimen should be minimal and infrequent but consistent.

It is important to consider Peacocks' natural habitat when contemplating how to arrange the aquarium they will inhabit. Sand is the substrate of choice. Gravel with its sharp edges may irritate their gills since they frequently “chew” and “sift” the substrate after each feeding. Furthermore, males like to dig shallow depressions in the sand prior to spawning, which is less likely to occur if gravel is used.

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Rocks are an important consideration. The vast majority of Aulonocara species exported for the aquarium hobby are rock-dwelling cichlids. Specifically, they inhabit the intermediate zone, where the deep, open sand meets the rocks. They cling to the rocky niches of this biotope, which afford them much-needed protection on account of their relatively small size. In the aquarium, they likewise appreciate rockwork. Caves or large crevices are readily claimed and the areas in between or near rocks prove to be favorite places for breeding. A simple alternative to rocks are clay flowerpots. While not as aesthetically pleasing, they are quite functional. Some creative aquarists will even glue sand to pots and plastic pipes to disguise them. This can be done using 100% silicone or a hot-glue gun.

In the aquarium, live plants are a viable option. Peacocks do not eat plants, unlike other Lake Malawi cichlids, but they nonetheless have a tendency to dig and uproot them. All plants should be fastened or secured. Java Fern should be tied to drift wood or rocks with black string or fishing line. Other plants should be potted (when possible) and wedged in between rocks. Even though Peacocks have adapted to a dimly lit environment in the wild, they readily adjust to the higher light levels required for the growth of aquatic plants.

The water in Lake Malawi is quite alkaline, although minor differences from location to location have been observed. The average surface temperature ranges from 74 - 82˚F (23 - 28˚C), depending upon the time of year and location (Konings 2001). Being a large body of water set in the tropics, its fauna is never subjected to rapid changes in temperature or chemistry. In the aquarium, efforts should be made to create as consistent an environment as possible. The temperature of the water should be stable, without sudden fluctuations. A reliable heater will help maintain a fairly constant water temperature. A long-standing rule of thumb for getting the appropriate size heater is to select a heater with a rated wattage equivalent to 3 watts per gallon of aquarium water.

In addition to a stable water temperature, attention must also be paid to the water chemistry. The first step to creating stable water chemistry is to “harden” the water. GH and KH levels
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of the water should be no lower than 10. Levels lower than this will result in an unstable pH environment no matter how much effort or money is put into raising the pH. Water can be hardened with the use of chemicals, but the simplest (and least expensive) method is to use appropriate rocks. Limestone, for example, is made of Calcium bicarbonate, a natural buffer found in many biological systems. In the aquarium, it aids in resisting any deviations from the desired pH level of 7.8 – 8.0.

In the lake, males are solitary and territorial. Males' territories are usually 0.5 m in diameter and typically center around a crevice or a rocky overhang, which functions for rear cover and offers escape. In contrast, females live solitary or in small groups and usually linger near the males' territory (Spreinat 1995). Keeping this in mind and relying on aquarists' experiences over the last three decades, it is generally recommended to keep Peacocks in a ratio of one male to two or three females.

Breeding Peacocks in the aquarium is generally not very difficult. Courting rituals are both vigorous and prolonged, making them very exciting to watch. In the lake, males typically display at the entrance of a cave or grotto, where they have dug a shallow spot in the sand (Staeck 1981). They will display with their fins erect and oftentimes their thin, lateral bars darken. Courting males make darting, flashing movements in an effort to gain the female's attention. Once a male has attracted a consenting female, he will lead her to this shallow nest. They will make several passes across the nest in the classic T-position before the female finally drops a few eggs. Just as the female reaches to pick them up, the male fertilizes the eggs. The two will repeat this process dozens of times, and it seems they only stop when the female eventually loses interest. Once spawning is complete, the female will incubate the eggs in her buccal cavity for a period of 21 to 28 days. When the fry are developed enough to swim and forage on their own, she will release them. In the wild, a mother will care for her young for the first week or more but this is only rarely observed in the aquarium. Depending upon the size of the female, spawns of most adult Aulonocara species number between 12 and 50 eggs and newly released fry measure roughly 10 mm. Most aquarists prefer to keep their aquariums in the range of 78 - 82˚F (26 - 28˚C) on the grounds that spawning occurs more readily when these fish are kept in warmer water (Loiselle 1988). Warmer temperatures will also speed the development of embryos within the mother's mouth, effectively reducing the “holding time” and thereby decreasing the duration of time between spawns.

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In the aquarium, where space is limited, males will continue to drive females for several days after spawning. It is essential that females have shelter from pursuant males. Without shelter, females often abort the incubation. Female Peacocks do not eat during the incubation period. As a consequence, they can become weak and easily stressed if chased and nipped at repeatedly. For this reason caves and other shelter are necessary. In some instances temporary placement in another aquarium is the best plan. Brooding females can be removed from the aquarium and allowed to pass the incubation period apart from other fish without fear of causing her harm. It is recommended however that she not be removed immediately after spawning. The stress of removal shortly after spawning can lead her to abort the clutch. If a female is removed, consider allowing her three to seven days post-release to recover her strength before returning to the aquarium. When cared for properly, females will breed about every eight weeks (four weeks post-release). Regular water changes and a diet high in protein will keep them in top condition.

Aulonocara species are known for their tendency to cross-hybridize; consequently, many responsible aquarists refrain from keeping more than one breeding group in the same aquarium. It is possible; however, to keep different species together if these are selected properly (Konings 2002).

Cross-hybridization is obviously not a problem if one plans to keep only Peacock males. The setup would prove a cornucopia of
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color as males do not require the presence of females to display their full coloring. Be aware that some males may not display their full potential if housed with others of similar coloring even though there may be no apparent aggression between the two fish. This is especially true of the yellow-bodied Peacocks.

Peacocks can be housed with a variety of other Lake Malawi cichlids. Many of the gentle, medium-sized haplochromines make excellent tankmates. Various members of the genera Copadichromis, Cyrtocara, Placidochromis, Protomelas, Otopharynx, Nyassachromis, and Sciaenochromis are some of the popular fish which are often housed successfully with Peacocks.

Not all Lake Malawi cichlids make suitable tankmates. Peacocks should not be housed with Mbuna or other boisterous cichlids such as Labeotropheus, Petrotilapia, Metriaclima, or Pseudotropheus species. While it is true that Mbuna and Peacocks both live in the rocky biotopes of Lake Malawi, they infrequently have contact. Peacocks typically reside at a depth of 6 to 40 m; Mbuna on the other hand, are usually found in the upper 5 m of the water column (Spreinat 1995). The reason for this difference is due to dietary differences between the two groups. Mbuna graze the algae growing on the rocks in the lake. The algae require strong light in order to flourish. Peacocks live at depths far too deep for the algae to grow in abundance. It follows therefore that Peacocks and Mbuna are not natural conjoiners.

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Mbuna and Peacocks make poor tankmates primarily because Mbuna have a considerably more aggressive temperament (some would even say obnoxious). Their aggressiveness and hyperactivity have a tendency to stress the Peacocks. Keeping Mbuna together with Peacocks usually proves deleterious to the latter who are kept in a constant state of subordination. Some hobbyists who mix these two fish may argue that no such unfavorable conditions exist. This may sometimes appear superficially to be true, but Peacocks kept with Mbuna do not grow as fast, are less colorful, and do not live nearly as long. Peacocks removed from such an environment show dramatic turnaround within a short period of time, confirming the sensibility of this recommendation.

As you can see, the Peacocks of Lake Malawi are exquisite fish with a remarkable specialization. Their striking colors, ease of care, relative peacefulness with other fish, and their prolific aptitude have made them a mainstay in the hobby. With dozens of color patterns, you're sure to find one that suits your taste. If you have never tried one of the Aulonocara species, I recommend giving them a try. You will quickly discover for yourself why they remain a hobby favorite after more than three decades. □

Literature Cited

  1. Eccles, David H. And Ethelwynn Trewavas. 1989. Malawian Cichlid Fishes; the Classification of some Haplochromine Fishes. Lake Fish Movies, Herten, West Germany.
  2. Konings, Ad. 1995. Cichlidae Live Part 2: Diving in Lake Malawi. Trophic Adaptations. Cichlid Press, El Paso, TX.
  3. ____. 2001. Malawi Cichlids in their Natural Habitat, 3rd ed. Cichlid Press, El Paso, TX.
  4. ____. 2002. “Malawi Cichlids”. Enjoying Cichlids, 2nd ed. Ed. Ad Konings. Cichlid Press, El Paso, TX.
  5. Loiselle, Paul V. 1985. “Butterflies and Peacocks from Lake Malawi”. Freshwater and Aquarium Magazine, Mar 1985; pp. 10-21.
  6. ____. 1988. A Fishkeeper's Guide to African Cichlids. Tetra Press, Blacksburg, VA.
  7. Spreinat, Andreas. 1995. Lake Malawi Cichlids from Tanzania. A. Spreinat, Göttingen, Germany.
  8. Staeck, W. and H. Linke. 1981. Afrikaniscae Cichliden. II. Buntbarsche aus Ostafrika. Tetra-Verlag, Melle.
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