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Crenicichla marmorata:
Observations in nature
by Oliver Lucanus
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| A Crenicichla
marmorata breeding pair in their natural habitat. |
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It is not unusual to see Crenicichla among the discus
schools because they both occupy the few tree trunks in the shallows.
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| The lake is fed by several small
clear water streams before overflowing through a short canal into the
main stream of the Amazon. Beyond the canal, none of the cichlid
species found in the lake and in the feeder streams occur in the main
channel of the Amazon. |
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| This tiny stream drains water from
nearby hills. The stream is just 6 feet (1.8 m) wide and only up to 8
feet (2.4 m) deep. |
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| The stream has a fast flowing under
current, and there is little sediment on the fine white silica sand.
Thousands of cichlids from a number of species swim into the onrushing
current feeding on insect larvae, shrimp, and other food items carried
downstream. |
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| Where the stream enters the lake
large amounts of debris are deposited. The water in this area is much
warmer and moves slower. Many cichlids breed in this region. |
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| Pairs of Crenicichla marmorata use branches
stuck in the bank to burrow caves beneath. Eggs are laid against the
underside of these branches and the larvae are at first kept in the
cave burrowed in the soft substrate. |
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| Wild-caught pair of Crenicichla marmorata in the
aquarium. |
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| Males guard the perimeter around the
nest; they defend a circle of about 6-10 feet (1.8-3 m) from the
spawning site against potential predators and conspecifics. Species not
regarded as a threat, such as the smaller tetras and even the
Geophagine cichlids, are usually tolerated very close to the nest until
the young are free swimming. |
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| When the young hatch, the female
leads them through the shallow water to feed. The survivors of the
numerous larvae will remain with the female for the first year. |
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