Page 234 - Encyclopedia of Aquarium and Pond Fish, 3rd Edition

232 MARINE FISH: BREEDING

The male carries
REPRODUCTION IN CLOWNFISH the eggs until
they hatch,
If two clownfish spawn successfully, they are likely to continue breeding which is usually
about a week
throughout the year. In fact, well-fed specimens may spawn as regularly after spawning
as every month or six weeks. Not surprisingly, tank-bred clownfish tend
to reproduce more readily in aquariums than wild-caught specimens.
The clownfish choose
a spawning site near
the base of their host
anemone so that they
can retreat among
its tentacles if danger
threatens. After they
have cleaned the site,
the female lays her
eggs. The male releases
his sperm over the
eggs to fertilize them.

An adhesive coating
glues the eggs to the
spawning site. The male
is largely responsible
for guarding the eggs
and will attack any
would-be egg-stealers.
He fans the eggs with In Yellow-headed Jawfish,
his fins to improve the male undertakes the
water flow so that task of mouth-brooding the
they receive a good eggs. The fry initially live
supply of oxygen. close to the surface but
swim down to the bottom
when they are about three
The color of the eggs weeks old. Jawfish inhabit
changes from orange to burrows excavated in the
dark brown during the substrate, where they
incubation period. With spawn during the warmer
a diameter of ⁄32 in months of the year.
1
(1 mm), the eggs are
among the largest laid The female lays her eggs in the male’s abdominal pouch, where
by any marine fish, and
far larger than those of they are fertilized. The fry hatch in the pouch and emerge as
egg-scatterers. The eggs free-swimming young. A few marine species practice internal
hatch after 7 to 10 fertilization (see p.61) and give birth to live young.
days, usually at night.
Removal of eggs and fry
The adults show no Eggs and fry make tasty meals for many tank occupants, fish
interest in the fry, and invertebrates alike, and generally stand a better chance of
which should be moved
to a rearing tank until survival when they are moved to less hostile surroundings. This
they are large enough is not as simple as it sounds. Egg-scatterers spawn at night, so if
to survive in the main you are not prepared for the event, most of the eggs may be
aquarium. It may take
three weeks for the fry devoured by the time you check the tank in the morning. If
to obtain their full you manage to reach the eggs in time, scoop them out with a
coloration. The juveniles cup and transfer them to a hatching/rearing tank. Clownfish
shown here are about
three months old. and other egg-depositors guard the spawning site, so there
is no need to move the eggs, and the protective behavior
of the adults is fascinating to watch. If you insist on moving

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