The thing to know about spawning red shiner -- and virtually any Cyprinella
-- is that they're crevice spawners, depositing their eggs in crevices in
submerged logs, loose bark on fallen trees, tree roots, and other woody
debris, or in the cracks between rocks and boulders.
Another interesting tidbit: Unlike most other minnows, in which the females
deposit most or all of their eggs at once, Cyprinella are "fractional
spawners," so called because females deposit only a fraction of their eggs
during each spawning act. As a result, the Cyprinella breeding season can
last from the spring through summer, and even into autumn in some areas.
Fractional spawning is said to increase reproductive potential by reducing
the number of larvae that compete for food and space at any one time. It's
also a wise strategy for fishes that are choosy about where they spawn;
since the number of appropriate crevices in any given stream may be limited,
fractional spawning allows Cyprinella to reuse the same sites week after
week after week.
Artificial spawning crevices can be constructed out of two terra cotta tiles
stacked one on top the other. Separate the tiles with a piece of felt or a
few silicone beads, and offset them so that the bottom tiles protrudes a
centimeter or so. Studies have determined that a 3 mm-high crevice is
preferred by red shiner over other heights. Robert J. Goldstein reports red
shiner spawning between the pleats of Magnum canister filter cartridges.
After spawning, move the filter cartridge to a wide-mouth glass jar with
vigorous aeration. Newly hatched red shiner require small food items such as
rotifers, infusoria, and green water for the first two or three weeks. Fry
can start taking powdered flake food at half an inch, and whole flakes at
In addition to spawning crevices, captive red shiner should spawn in just
about anything: green acrylic yarn (simulating a bed of plants) anchored on
the aquarium bottom, Java moss, and in artificial gravel piles constructed
out of variously sized glass marbles. If you use a non-creviced spawning
medium, be sure to remove the parents after spawning as they will eat the
eggs. As fractional spawners, red shiner will spawn in captivity as
frequently as every 48-72 hours. Spawning occurs most often in the early
morning, almost immediately after the aquarium lights are switched on. One
scientiist has hypothesized that if the lights are never turned off,
sexually mature red shiner will continuously produce eggs and spawn until
Don't know what to say about your male red shiner looking like as if he's
got something in his mouth. Maybe he's eaten eggs or fry. Or maybe he's just
displaying...to attract females and to scare of competing males.
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