This site is primarily about the African annual fishes of the genus Nothobranchius, however I have included some content on some semi-annual fishes. There are a few articles on fish and livefoods, book reviews as well as a fish and egg list, but the majority of this site is made up of photographs of Nothobranchius, (part 2)
Annual fishes, as the name suggests, complete their life cycles within a year, their eggs requiring a dry period to develop fully. These fish occur in temporary pools in certain areas of East Africa and South America, areas that are subject to seasonal rainfall- creating these bodies of water. As the year progresses, the water levels drop, and after several months dry up completely. Unlike fish such as the lungfish, which survive the dry season, annual fish bury their eggs in the substrate, and die when the pool evapourates. A few months later the rains come again, bringing life to the pool, and allowing the now fully developped embryos to hatch. The weather is always unpredictable, so the fry must grow quickly, reach maturity and reproduce before the pool dries up again. In general they are fast growers, reaching adulthood after a few weeks. Sometimes the fish won't make it, however, but this does not spell the end for the population. The eggs go through several distinct stages in their growth, including resting periods called diapauses. A few of these embryos will either stop, or at least slow down significantly their development- they will not be ready to hatch for some time after their siblings. In this way there are always eggs ready to hatch, whenever the rains come.
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