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Alcolapia alcalicus by Greg Steeves |
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The title of the email read: “You’ll never guess where I am”. As I opened the attachment from my friend Lawrence Kent, a strange but incredible fish appeared. It was Alcolapia grahami and he was in Kenya at Lake Magadi, one of the soda lakes about 85 km (53 mi) southwest of Nairobi near the Tanzanian border. He sent me a series of photos not only to heighten my jealousy, but Lawrence knew I maintained a closely-related cichlid, Alcolapia alcalicus. A. alcalicus is found at Lake Natron, another 40 km (25 miles) southwest of Lake Magadi. The genus Alcolapia consists of four species: the aforementioned A. grahami from Lake Magadi, A. alcalicus from Lake Natron, A. ndalalani from the southern lagoons also of Lake Natron, and A. latilabris which can only be found in particular springs at the southern extremes of Lake Natron. A. alcalicus has been introduced in Lake Nakuru in Kenya, another soda lake along the right arm of the African Rift Valley. Ten thousand years ago this region was a single very large shallow lake basin. | |
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Alcolapia species are tilapiines. The name is derived from Arabic; “alco” referring to alkaline, a description of their harsh native water chemistry, and “lapia” as in tilapia. All members of the genus are somewhat similar in regards to overall appearance. They are torpedo-shaped with distinctive finnage. These are all small cichlids ranging from an adult size of 62 mm (2.4 in) for A. ndalalani, to 12 cm (4.7 in) for A. alcalicus. Up until the turn of the last century, Alcolapia was a subgenus of Oreochromis. Oreochromis are mouthbrooding tilapiines. Seegers and Tichy in 1999 released a study showing both molecular and body structure differences that elevated Alcolapia to genus status. They also showed that evolutionary radiation is occurring in the soda lakes creating new species along with distinct location variants. The thinking is that areas of these waterways are too inhospitable for even the soda lake cichlids. These caustic regions serve as barriers and separate populations, which allows for divergence and diversification. To my knowledge, the only member of this genus currently in the hobby is A. alcalicus and it is not exactly readily available. Soda lakes are considered to be the most hostile waters on the planet that support life. They are situated in a volcanically active area where evaporation has drastically increased both salinity and alkalinity levels. In Lakes Natron and Magadi, the pH is around 10 while the salinity is just under 10%. Areas of these waters contain open fissures where expelled volcanic gas can heat the water to in excess of 50 °C (122 °F). In Lake Natron, these mineral rich hot springs heat the shallow waters where salt-loving (halophile) organisms thrive. This includes cyanobacteria (blue-green algae) whose orange coloration often tinges the water. Here, huge flocks of lesser flamingos feed on the endemic algae as does A. alcalicus. In the areas around the heat releasing fissures, the much sought after algae mats grow thick. The fish play a deadly game of rapidly jumping into the scalding water, tearing off a chunk of food and getting back to cooler water before they cook. The odd floating A. alcalicus body shows us that the fish does not always win. | |
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All four Alcolapia species are quite attractive. I think that an adult A. alcalicus male is a show-stopper and even non-fish people, when entering my fish room, are drawn to this species. The male’s long slender body is adorned with scales that have a brilliant metallic blue-green sheen. The head is colored with dull orange-yellow hues and the underslung mouth is lined with white-blue lips. The first several rays of the pelvic fins are black fading to hyaline. The pectoral fins are colorless. The anal fin is rimmed in black while the front portion is baby blue. The remainder of this fin is clear but speckled with white dots. The caudal fin is spotted with small light blue or white dots while the background coloration is tinged red. The large sail-like dorsal fin is mostly black with light dots between the rays. It is a most remarkably colored fish. The largest of the males will display the most vibrant coloration but even smaller, less dominant individuals will exhibit pleasing color and finnage. The female has the same body shape but lacks the brilliant colors of the male. She is typically a silver-tan color with transparent fins. I first got the opportunity to work with A. alcalicus several years ago. In preparation for their arrival I studied native conditions including salinity, pH, and conductivity. Before this time I had no idea what a microSiemens even was. All I needed to do was replicate a thermal pool biotope made from the vent of an active volcano. What could be so tough about that? After all the advance work with meticulous attention to water parameters, I was able to kill them all off one-by-one within two weeks. I knew these were an extremely rare cichlid and following this failure, I was willing to leave their well-being to someone who was much more willing to alter water conditions than I was. Fast-forward a couple of years. I was once again presented with the opportunity to work with a group of these soda lake cichlids. Being a sucker for punishment I agreed to try my luck once again with a small group. They arrived on my doorstep two days later. My enthusiasm neurons are not directly connected with the part of my brain that controls planning. I had a bag of fish and no tank prepared for them. As if already condemning them to death, I placed them in an empty 20 gallon (76 liter) aquarium with no décor and a small air-driven sponge filter, until I could ready appropriate quarters for them. Planning on taking care of their housing the next day, the time continuum extended and it became the next week… and so on. In the meantime, the small fish in the untreated tank were not only surviving but thriving. They were eating the same flake food I fed most of my other fish (largely haplochromines) and appeared to be growing. As they put on a little size in the small tank, I got around to setting up a 125 gallon (473 liter) tank as their permanent residence. At this point in time I saw no reason to alter my water in any manner. It comes out of the hose with a pH of about 8, substantially lower than what their native waters would be. Being summer in south Texas, the water temperature is in the high 80s °F (27+ °C), but I use no heaters in my aquariums. A. alcalicus does not mind the warm fish room temperatures I experience in the summers and have even survived the low 70s °F (low 20s °C) in the winters. So, as you can see, my secret to successfully maintaining A. alcalicus is to do absolutely nothing. These fish are, after all, tilapiines and have likely thrived in Lake Natron solely because there is no competition for food or space in this harsh environment. Their aquarium is filtered by two large air-driven sponges. The substrate is fine white sand with a few piles of slate stacked to form caves. There is ample open water with several Anubias and Aponogeton species spaced to green things up. Biweekly water changes of about 25% keep everyone happy. The setup is very simple yet apparently to the liking of A. alcalicus. In a stark contrast as to what I am used to with my haplochromines, these fish are active but communal and not at all aggressive with each other. I have not witnessed any establishment of a hierarchy with the females, no top dog or formation of a pecking order. Males will occasionally flare up at one another but I have yet to see so much as a torn fin. Although I have never seen the males doing any excavations, I commonly see small pits dug into the substrate. I had presumed that this is where the male creates a territory and where spawning takes place. I was wrong. | |
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Fortunately I’ve gotten frequent spawning from my group. It is sometimes difficult to tell if a female is actually mouthbrooding due to the rounded shape of the head. Their buccal cavity is not as pronounced as it is with my haplochromines. Until recently I had never witnessed the act of spawning but, as I said before, I had figured it was fairly typical to what I was used to. In a nutshell, the male builds a spawning pit, defends it against all other fish except for a gravid female that he spends his time showing it to. This might include flaring his fins and shaking, all the while trying to lure the female back to his excavation. Here the male and female will circle each other, her dropping eggs, him fertilizing them, her scooping them up, and repeating this process until her mouth is full. I was incorrect in all counts! A short while ago I was able to shoot some video of the spawning process. The pair I witnessed did not spawn in the depression the male had dug, but rather on the highest point of rockwork in the tank. This was a flat surface, slightly diagonal. The male approached the female, not with extended fins trying to look all masculine, but with almost clamped fins and his body bent into a strange arc. He and his female took position at the top of the rockwork and began shaking together. This was not the circular shaking done by my haplochromines, but rather a stationary vibrating beside each other. Both female and male had a small “nipple-like” protrusion on the underside of their abdomen. The ovipositor in the female is a tube where the eggs are released while the male’s appendage releases milt. The female releases one egg at a time and upon being expelled, it rolled down the incline to a small depression where it was collected. She would then keep in position but swim backwards, pick the egg up and move forward to repeat the process. All the while the male did not erect his fins but rather continued displaying that strange arc thing that the female must have found attractive. The only time he flared up was when a rival male swam too close to the spawning spot. The breeding male would rear up on his haunches and chase the other male A. alcalicus away. Once spawning was over, it was business as usual. The male integrated back into the group as did the female who was not harassed in the least. She did not pick a secluded spot to brood but mingled with the other fish, even nipping at scraps of food when offered. I might add that the spawning procedure I witnessed from A. alcalicus is quite different from observations made of A. grahami in their native waters. A. grahami constructs a large step lek with several smaller satellite pits around the perimeter (Albrecht 1968). Alcolapia alcalicus is a maternal mouthbrooder. When young, first spawns are very small with 6-8 fry to be expected. Once the fish have grown considerably, clutches of over 20 fry are normal. Much like haplochromines, the fish incubate the eggs for up to 18 days. At this point in time I generally isolate the fry to a tank of their own so I am unsure of how long female parental care continues post-release. The fry grow quite quickly on a diet of crushed tropical flake and ground up powdered pellets. During the time I have been working with A. alcalicus I have always kept the breeding groups in large tanks. I started out with a species-only aquarium and eventually added a group of six Synodontis ocellifer to the mix. This worked well as I have never noticed the two species interacting at all, and admittedly, I enjoy some diversity in my displays. As of late I have housed them with another unusual tilapiine, Oreochromis esculentus. Again, the species are not bothered by one another and add to the allure of the aquatic environment. I will add that none of the three species have bothered the live plants which are thriving as well. I would think that some of the smaller Coptodon species such as C. bythobates would make acceptable tank mates as well. | |
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The International Union for the Conservation of Nature has given a red list category of VU (vulnerable) to A. grahami, A. latilabris, and A. ndalalani and EN (endangered) to A. alcalicus. This ranking is mirrored by the C.A.R.E.S. Preservation program. I am aware of several hobbyists that are actively working with A. alcalicus and successfully propagating it. Ideally, there will come a time in the near future where captive stocks might just outnumber wild fish. Hopefully we will get a chance to prove our mettle with the other three species of Alcolapia but until that time, I am extremely privileged to have worked with such a unique fish and share a bit of satisfaction knowing that my breeding success has allowed others to enjoy the species as much as I have. Now, to get some breather bags to Lawrence…. Albrecht, H. (1968) Freiwasserbeobachtungen an Tilapien (Pisces, Cichlidae). Ostafrika Zeitschrift fur Tierpsychologie, 25: 377–394. Seegers, L. & H. Tichy. (1999) The Oreochromis alcalicus flock (Teleostei: Cichlidae) from Lakes Natron and Magadi, Tanzania, and Kenya, with descriptions of two new species. Ichthyol. Explor. Freshw., 10: 97–146. |
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