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Originally published in Buntbarsche Bulletin # 153, December 1992,
One glance and you learn nearly all you need to know about pike cichlids. These are elongate, torpedo-shaped fish admirably adapted for life as piscivorous ambush predators. They have long snouts with large, teeth-studded protrusible mouths that enable them to grab and the swallow whole dietary fish. They take their common name from the ultimate ambush fish, the pike, Esox species, however, they are not at all related. They are cosmopolitainly distributed throughout South America in all three water types, and are found both in swift-moving rivers and streams (lotic habitats) as well as shallow, quiet inlets and backwater pools, even swamps (lentic habitats). Youngsters are frequently found in calm backwaters, mature adults in strong current, and brooding parents in slow-flowing bays and side-arms (Kullander, 1986). While many Crenicichla species are enormous, growing to total lengths of more than 18 inches (Lowe-McConnell, (1969) reports taking an of Cr. saxatilis from a trap that was this long!), there are a number of dwarf species in the 4-6 inch range. One gets no longer than 2 1/2 inches. There are also a number of rheophilic species from the torrential rapids with reduced swim bladder that hop rather than swim. Pike cichlids have successfully invaded most South American biotopes. Gut analyses suggest that they depend on a diet of insects, insect larvae, shrimp and, in the case of the non-dwarf forms, fish (Knoppel, 1970). Interestingly, a fair percentage of plant material , in some cases nearly 50%, was found amongst the meat in the stomachs of some pike cichlids! Observation in the wild suggests that some of the larger species are solitary in habit, which might account for their belligerence in aquaria, but juveniles, and some of the dwarf species are downright sociable: Kullander (1990) recently described Cr. hemera from the Rio Madeira choosing the specific epithet hemeros, a Greek adjective meaning tame , with reference to the docile behavior of the type series when collected. From that same paper: Curiously, most individuals observed could be approached very closely. They fled reluctantly and not very far . These observations have been corroborated for a number of species in the aquarium. Moreover, they are excellent and gentle parents often staying with their fry for many months (see below) So, the generalization that all pike cichlids are nasty just isn t so.
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