Congo Killies - PageSuite

to their new surroundings, spawning
should commence within a week.
The other option is to over-winter
them in captivity, which was the
method I chose. Over-winter conditioning
entails a reduced photoperiod and
lowered water temperatures, preferably
into the 45–55°F (7–13°C) range for
up to two months; however, I successfully
conditioned them by dropping
the temperature down to the low
60s Fahrenheit. Exposure to indirect
outdoor light is beneficial, and based
on my initial experiences this exposure
to natural photoperiod fluctuations is
a more important conditioner than a
large drop in temperature. Many of the
references to darter breeding that I have
read list water temperature as an important conditioning
factor for Rainbow Darters, but the water temperature in
my spawning tank did not get below 60°F (16°C). The
aquarium was exposed to natural lighting from southfacing
windows, so the fish were exposed to natural fluctuations
in the photoperiod. The females still became
visibly swollen with eggs and the males colored up.
I look forward to testing limited temperature drops
and exposure to natural light cycles on other native
fishes from my area.
Post-spawning
behavior in the
author’s Rainbow
Darter aquarium.
her, but once she starts eyeing the substrate he becomes
very interested and rushes to her side with his fins fully
extended. The female dives head first into the gravel and
pushes forward until just her snout and the top of her
tail are exposed. She lays a small number of eggs in the
The making of new gems
Spawning is initiated when the female enters the
spawning area. The male may or may not display to
Rainbow Darter
eggs with prominent
eyes developing.
Inset, newly hatched
Etheostoma
caeruleum fry.
AMAZONAS
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