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SUCCESSFULLY SPAWNING AND RAISING
THE BLACKBANDED SUNFISH (Enneacanthus chaetodon)
By Peter R. Rollo
In their native habitat in South Central New Jersey, spawning generally
begins in May or when the water temperature approaches 70 F. On June 20,
1994 I collected two dozen Blackbanded Sunfish, ranging in size from
juvenile to adult. No pregnant females were caught so I assumed I missed
spawning. With two dozen fish I was sure I had several pairs. The water
conditions found at the time of collection were no measurable hardness,
pH of 6.0 and a temperature of 75 F.
From the literature the spawning process proceeds in typical sunfish
fashion. The males construct a nest in the substrate and await a ripe
female. With the approach of a female, the male begins to display with
fins fully extended. The pair circle each other and after a short time
the pair stops circling, the female releases her eggs and the male
simultaneously fertilizes them. The males then remain on their nests to
fan and guard the eggs. I maintained the Blackbanded Sunfish for the
summer in a "community" style 29 gallon aquarium in the house. The 29
gallon tank is equipped with a Whisper 1 power filter with a home made
water current dissipator at the discharge. In their natural habitat
there is virtually no water current present. I am able to get adequate
filtration with minimal current. Aeration is provided by a bubble wand
attached to the back of the tank. There is about two inches of gravel on
the bottom and except for a flower pot turned on its side and a few
rocks, the bottom is bare to facilitate cleaning and fry collection (I
will cover this later). To help satisfy their requirement of lower light
levels, the light is attached to the back of the aquarium stand above the
tank and a thick growth of Water Sprite is maintained on the water
surface. This arrangement reduces the light intensity significantly
while still providing enough light for adequate viewing. The adult
Blackbanded Sunfish will be wintered outside in my shed and housed in a
20 gallon high aquarium. Filtration is provided by an adjustable flow
Visi-Jet 100 internal power head attached to a sponge filter and an air
driven sponge filter. Lighting is provided by a florescent tube
suspended above of the tank. The light intensity can be lowered to
appropriate levels by adjusting the distance the light is above the tank.
An inch and a half of gravel is provided along with the aquatic plant
Elodea or Anacharis as it is sometimes called. This plant grows
especially well during the winter when the water temperature is below 50
F. Minimal heating is provided using a submersible heater set on a
timer. This arrangement prevents freezing or major drops in temperature.
The heat is manually controlled and used only when excessively cold. In
the summer this tank is attached to a chiller and maintained at an
optimal temperature of 70 F for spawning and raising of fry during the
hot summer months. Filtration is provided by a sponge filter attached to
the chiller intake line and by a power head attached to a sponge filter.
The shed is also equipped with a thermostatically controlled exhaust fan
to prevent heat buildups.
Initially I tried to acclimate the Blackbanded Sunfish to my tap water,
which is hard and has a pH of about 6.8. They started off doing well but
within two weeks their health started to decline. Their appetites
decreased and the most noticeable change was that they lost most of their
color. Since it was clear they would not thrive on my terms I went to
work turning their tank water into a close duplicate of their natural
habitat. On July 8, 1994 my efforts began. The first problem to solve
was how to soften the water with the least effort. I decided to use a
rechargeable ion exchange softening pillow, which is placed in the filter
box. Using a five gallon container and an extra power filter, I softened
the water to levels that could not be measured by my test kit. I also
added Blackwater Extract to the softened water. The softening process
takes about one and a half to two hours per five gallons. Prepared water
is stored in five gallon bottled water containers with lids. When I had
prepared enough water, I changed the water and observed any changes.
Within 48 hours the fishes natural color returned and they became active
and hungry again. Softening the water appears to be a very important
factor for maintenance of healthy fish.
The next problem was how to acidify the water. While softening the
water, I added pH Down to the water till I reached a pH of 6.0 to 6.2.
The fish were slowly acclimated to this new water. Once completely
acclimated I sampled the tank water pH and found it to be 6.8 instead of
6.0. I had neglected to consider that my tap water has a high buffering
capacity and the pH will rebound to higher levels unless you exhaust the
buffering capacity of the water. The next time I made water and adjusted
the pH to 6.0 I waited several hours and checked the pH again. It had
rebounded as it had in the tank. The pH was adjusted again and let to
sit overnight. This time the pH remained the same. As an aid to the
acidification and conditioning process, I also filter the water through
peat prior to storage or use. The completed water is tea colored, as it
is in their native habitat, and takes a day to make five gallons of
water, but with the results I have gotten it is worth the trouble. In
the summer the sunfish in the house are fed moderately every other day,
and in the winter, when they are in the shed, they are fed sparingly
every three or four days whenever the water temperature rises above 50 F.
Below 50 F the food in their stomachs digests so slowly that it can
actually spoil before digestion is complete, killing the fish. Besides,
I am trying to recreate their natural environment, and minimal feedings
in the winter is part of it. The foods offered in the summer include
fresh hatched brine shrimp, frozen and freeze dried bloodworms, frozen
glassworms, small live crickets, small live cut up garden worms, live
daphnia, frozen shrimp, live mosquito larva, live cyclops, live black
worms and any other small insect I can catch. The winter diet for these
fish will be the same as that in the summer except for some of the live
foods that cannot be cultured indoors, caught or bought. As with my
experiences with breeding Green Sunfish, the fish endured an average
summer temperature (in the house and shed) of about 80 F and will
experience average winter temperatures of about 40 F in the shed.
Thirty-three percent water changes are made once a week spring, summer
and fall. Twenty-five percent water changes are made about once a month
in the winter (when water temperatures are consistently below 55 F).
Don't be lax with water changes. These fish may be small but they have
big appetites and produce large amounts of waste. It is extremely
important that all water added to the aquarium during water changes be
the same temperature, pH and hardness as the water in the aquarium or you
run the risk of stressing or killing the fish. It is now early August
and all is going well. On August 8, 1994 I noticed that two of the
Blackbanded Sunfish appeared to be fanning eggs and were chasing the
other fish away from their designated territory. No nests were formally
constructed. They simply chose natural depressions already existing in
the gravel. I immediately began to consider the possibility that they
were spawning but had to be sure. The next night I noticed several fish
approach the guarded territories slowly and deliberately. Some were
immediately chased away and some were not. It appears rival males and
unripe females are chased away immediately while ripe females are allowed
to approach. To all approaching fish the guarding fish, or the male,
reacts by extending his fins and then seems to look over the approaching
fish. If the male does not chase away that fish the odds are very good
that it is a ripe female. The male then starts nudging her belly area
with his mouth and body while swimming in a circular path, with fins
fully extended, around the female at a 45 degree angle. The female stays
mostly upright in a normal swimming position during this process. The
male was devoid of color, but the females' color was intense. After a
few moments of this behavior they stop swimming, the female quivers, eggs
are released and simultaneously fertilized. The male then chases the
female away. Even during the spawning process, sex determination is
virtually impossible. Granted, there are color differences during
spawning, but immediately after spawning the colors of the male and
female return to normal and the sexes can no longer be distinguished.
During spawning when I briefly knew who was who it appeared the female,
when viewed from above, was broader across the top of her body than the
male. This is by no means very accurate but does serve as a guide in
approximating the sexes, especially when spawning is near. This spawning
process continued till the next day. The eggs are amber colored and
extremely small (no larger than 1/32 of an inch) and adhesive. Close
examination of the nesting areas showed eggs covering the nearby rocks.
The rocks were removed and placed into the rearing tank. I now anxiously
waited for the eggs to hatch. No chemicals were added for egg
protection. Clean, well filtered and aerated water is sufficient. Based
on my reference books the eggs of this type of sunfish hatch in 3-5 days
depending on temperature. The Blackbanded Sunfish eggs hatched in two
days on August 11, 1994 at a water temperature of 76 F and a pH of 6.2.
The wigglers were entirely clear and no visible markings could be seen.
Within 24 hours eye spots became apparent and the wigglers started to
take the form of fish 24 hours after that. Twenty-five percent water
changes are made every week and so far all is well.
With regard to how long it takes for the wigglers to become free
swimming, my references estimate a few days to about one week depending
on water temperature. By August 15, four days after hatching, all
wigglers were free swimming. I offered a very small quantity of brine
shrimp but none were taken. I fed them infusoria for the next two days.
Three days after all were free swimming brine shrimp were again offered
and accepted. Further experience has shown that infusoria is not
necessary. One to two days after the fish are free swimming they will
accept newly hatched brine shrimp. Feedings began twice a day, once in
the morning and once in the evening. The feedings require that the
aeration and filtration be turned down to a minimum. This prevents the
shrimp from being sucked into the filtration system and aids the somewhat
uncoordinated fry in catching their food. The young fry cannot
successfully capture the moving shrimp in moving water. With still water
it takes them several attempts before they can capture the shrimp. This
will quickly pass as the fish grow and become proficient swimmers. It is
easy to determine which fry are feeding. Since their bodies are still
transparent, consumed shrimp give the fry orange bellies. For variety
the fry are also given fresh hatched mosquito larva, live cyclops and
microworms. I estimate I have about 100 to 150 Blackbanded Sunfish fry.
The Blackbanded Sunfish have continued to spawn every week through the
first week of September, stopped spawning for the remainder of September
and have spawned twice in the first week of October. The last few
spawnings occurred in the flower pot and in one case they spawned in the
root mass of the floating water sprite due to the fact that the flower
pot was occupied by a male guarding eggs. He was not about to let any
others spawn anywhere on the bottom of the tank. It appears that the
Blackbanded Sunfish are adaptable and not particular about where spawning
takes place. In all Blackbanded Sunfish spawnings I removed as many of
the eggs and/or wigglers as possible to ensure that none would be eaten
but on one occasion I decided to let the male guard the eggs and fry to
see what would happen. He did as good a job as devoted cichlid parents.
He continuously fanned the eggs and chased away any fish that came close
to his area. Any wigglers that strayed to far were picked up in his
mouth and spit back into the nest. Once the fry were free swimming they
both went their separate ways.
Once the fish are transferred to their winter quarters spawning will
quickly stop as the water temperature drops. This will be a welcome
relief because all my available tank space is devoted to the rearing of
the Blackbanded Sunfish fry at various stages of development. This
spawning behavior is contrary to the literature which states that "The
Blackbanded Sunfish has a non-protracted spawning season and low lifetime
reproductive potential."1 The spawns have been small to moderate,
averaging about 15 to 75 eggs, and have hatched in two to three days.
When I notice a spawn area it is covered with sheer material supported by
a plastic frame (6" long x 5" wide x 4" deep) to prevent the eggs from
being eaten. The males can still see through it, continue to guard the
eggs and in one case spawned again on top of the egg guard. The wigglers
adhere to the inner walls of the material and the entire egg guard with
wigglers is carefully removed and placed in the rearing tank. So far
this is the best method I have devised to collect fry from the
Blackbanded Sunfish Community tank. Several months have passed and a few
of the fry are now between ª to ® inch, but most are about ª inch. The
fry are still dependent on brine shrimp, live cyclops and microworms and
attempts will be made to wean these fish off the live foods as soon as
they are large enough. I was successful in doing this with the Green
Sunfish and hope I will be able to succeed with these fish.
As they have aged, the young sunfish are beginning to show physical
attributes of adult fish. The Blackbanded Sunfish have developed a
horizontal black spot on the caudal peduncle and a vertical dark band
through the caudal fin. They also are developing black vertical stripes
and the two tone black and salmon colors on their first dorsal spines
(The first three dorsal spines are black and the fourth is salmon
colored) and front edge of their ventral fins. Their overall background
body color is gold-silver. From my experiences with breeding Green
Sunfish, cannibalism of the smaller fry by the larger fry began at about
this time. So far the larger fry have not attacked the smaller fry, as
did the Green Sunfish. My feeling is that their mouths are too small to
cause any damage at this age, let alone swallow their smaller tankmates.
The Green Sunfish were much more aggressive and equipped with large
mouths capable of easily swallowing their smaller tankmates. This group
of fish will be overwintered as naturally as possible in my shed as
described earlier, and I look forward to spring when I hope to experience
additional spawnings of the Blackbanded Sunfish.
REFERENCES
1.Wujtewicz, Donald. 1982. The Feasibility of Utilizing Minnows as Forage
in Farm Ponds. IV. A Life History of the Blackbanded Sunfish Enneacanthus
chaetodon in Hudson Pond, Delaware. Natural Resources Report No.3. 12
pp. Delaware State College, Dover, DE.
2.Thompson, Peter. 1985. Thompson's Guide to Freshwater Fishes.
Houghton Mifflin Company. 205 pp.
3.Quinn, John R. 1990. Our Native Fishes. The Aquarium Hobbyist's Guide
to Observing, Collecting and Keeping Them. Countryman Press. 242 pp.
4.Raasch, Maynard S. & Altemus, Vaughn L. 1991. Delaware's Freshwater and
Brackish Water Fishes. A Popular Account. Claude E. Phillips Herbarium.
Delaware State College. Dover, DE. and Society of Natural History of
Delaware. 166 pp.
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