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Continued
from previous page
Let's,
then, focus on the second and third group:
Cichlids
of the Rift Valley, mostly Tanganyikans, can be found in both groups
while up to now only one egglayer (namely Tilapia rendalli) is known
among Malawians. I must note that I'm less "sure" about
Victorians.
I
use - even if not FULLY correct - the terms egglayer
when referring to fishes (cichlids) that "lay" eggs on a
substrate. They should be called "substrate
spawner" and divided in
further groups according to the substrate they use: leaves, sand,
stones, bogwood and so on; but I do not feel the need to complicate
things that much; and mouthbrooders
referring to fishes that perform the "WHOLE" act from egg
fertilization to fry release "inside", generally speaking,
the female's mouth (some american cichlids, among them Geophagines,
are "partial" mouthbrooders,
meaning that not all the process takes place in mouth). My
experience with egglayer results from having spawned both Americans
("real" substrate spawners) and Tanganyikans (including
the shelldwellers, endemic to this lake, which reproduce inside
empty shells laying on sandy bottom). Since I referred to this group
let's go into further details:
Neolamprologus
brichardi:
Once a pair has settled (see below how to "get" a pair and
what risks are to be avoided) reproduction is almost
"unavoidable" if given some easy to get minimal
requirements. My shell dwellers spawned on or under stones, bogwood
and even on the tank's glass (!). Guard of eggs and fry is
"furious", with an amazing behaviour: whenever an
"enemy" comes close enough, one member of the pair attacks
him, thus while the enemy tries to escape this attack by turning to
the left or right, immediately the second of the parents attacks the
intruder who can't avoid being hit! Following generations remain
with the parents, cooperating in the defense of the younger ones,
while the "main" pair will only produce eggs and take care
of intruders. In the long run this fish can "overcrowd" a
tank to such a degree that there is really no room left for anyone
else. Once the center of the colony with passing generations has
become too large, a new pair is formed and settles down starting a
new colony… I had to get rid of my pair because of the lack of
space to host their fry!
Neolamprologus
brevis/multifasciatus:
Those both are egglayers that reproduce inside empty shells laying
on the sandy bottom. (See "fast
facts" sheet on the
latter).
Labidochromis
caeruleus "Electric Yellow" (LM), Ophtalmotilapia
ventralis "Mpimbwe"(LT), Haplochromis nyererei (LV)
(See "fast facts" sheet
on H.nyererei
and O.ventralis)
and all the other mouthbrooders, regardless of the lake they came
from, have reproduction habits which show a great degree of
similarity. Among them, courting and spawning in the so called
"circling position" (referring to position of members of
the pair). Eggs are layed in a sand nest or on a flat rock with the
notable ecception of the "real" Copadichromis chrysonotus
which spawns in the Malawians manner in open water (I have a pair
who layed eggs few times but, sad to say, with no
"results"). Either way the eggs are fertilized by the
male, picked up by the female (to my knowledge there are biparental
mouthbrooders although only among Tanganyikans). The collected eggs
are kept in the buccal cavity and "chewed" (to oxygenate
them) till, after a period of up to four weeks, the result of this
unbelievable effort is "spitted": a group of "scaled
sized" fishes similar in all but size to their parents! Because
of the well known aggression of most of these species, the fry at
birth they show the female colour and pattern. After release - for a
period of several days to a couple of weeks - the whole fry stays in
a group, which (in case of "danger") is
"swollowed" by their mother. I observed this behaviour
only once in my tanks by a female H. nyererei (out of two). Only
after they're too big to fit in their mother's mouth the males of
the group begin to (slowly) get their "true" colour,
pattern and temper! Sexual maturity is reached at about one year of
age.
Finally
let's review how to get a (possibly)
spawning pair of cichlids, their spawning needs and note the most
common mistakes that occur when trying to spawn cichlids. The most
common mistake and, at the same time the simplest to avoid is :
Not
meeting the Minimal requisite to get a spawning.
Despite
of all your best efforts a tank is, for lot of reasons, something
"different" from the real environment our friends come
from (this topic is of high importance when it comes to keeping and
/ or spawning F0 specimens). Nevertheless it is possible to spawn
almost every cichlid. Some are more difficult to spawn than others
or claimed to be so like Discus while with others it is almost
"unavoidable". Anyway, the spawning requisites can be
resumed like this:
-
Give'em
enough room (imagine keeping a pair of Nimbochromis in a 80 lt
tank) in a "correctly aquascaped" tank,
-
Give'em
well cycled and managed water with temperature and water
chemistry that fits to their own requests,
-
Feed them
according to their needs.
Most
common difficulties, and mistakes.
Odd
as it may seem, in some cases having a "real" pair is NOT
that easy (!) Luckily enough it's not that difficult with Malawians
but many other cichlids have a less detectable sexual dimorfism and
dichromatism - if any at all.. Generally speaking, the way to go is
to choose a group of young specimens, grow them up in a
"community" tank and once a pair is detected move it to a
spawning tank. Needless to say, this is a time and space consuming
process but with most americans it is almost the only way to go (the
other way is "venting" them which means inspecting their
pelvic area to see who's who). Other (less precise) ways to detect
sexes are more pointed fins, bigger size, brighter colours (in
males) but this allows much room for mistakes. It worths noting
that, few years ago, I grew up 6 Geophagus
brasiliensis to their full size (over 30
cm, or 1 foot each) only to see them turning into six males! The
idea of putting together two specimens of definite opposite sexes
will usually work with africans from the Rift Valley, while it is
less "sure" with others. However, I tried it with T. Meeki
and worked perfectly! To make things worst, cichlids, by
themselves, now very well what to do (and most of them have a REALLY
high genetic compatibility) which leads us to the worst
"mistake" a serious cichlids keeper can make. Producie,
possibly fertile, hibryds with low - if any - relationship with
specimens living in the wild.
Finally
a suggestion: whenever an (African) mouthbrooder is carrying you
should resist the idea to "strip" her after two weeks or
so of incubation (which means force her to spit the
"cargo" once the fry is big enough to survive). This is a
practice followed in order to get the maximum possible results (in
number) but this will likely result in "weaker" males and
females with the possible bad attitude of spitting / swollowing
eggs. Must add that not all cichlid keepers agree on this point but
that's what I prefer when things go on "naturally". If
you are really interested in high numbers of fry just
"net" the female, move her to another tank (you can try
two females, of different but "suitable" species, in the
same tank, provided you can have a, constant, close look to them to
be sure there is nothing going wrong with them …) and leave her in
peace till her time has come. She knows pretty well what to do, and
needs no "helping hand" at all! I arrived to this decision
through my personal experience (of actual stripping) in the
beginning of my story of cichlid keeping. Any way, keep in mind that
in a correctly set up tank a survival rate of 10-15% is almost
normal. Provided you have enough room allow the female to recover
her fitness for two - three weeks before bringing her back to the
male. This point is crucial if this specific fish is kept as a pair
and not a charem! |
