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Pass it on....

              THE GREEN SUNFISH (Lepomis cyanellus)
                       By Peter R. Rollo,
                        2308 Cedar Lane,
                           Secane Pa,
            North American Native Fishes Assossiation

In  Southeastern Pennsylvania, spawning begins in early  June  or
when  the  water temperature approaches 70 F.  In the  summer  of
while  on  a  fishing  trip in mid June, I was  able  to  observe
Bluegill,  Pumpkinseed,  and Redbreast Sunfish  performing  their
spawning  ritual.   The  spawning species were  verified  when  I
caught  a few of the fish on my fishing rod.  I was not  able  to
observe  the  nest  building process, as the  males  had  already
completed  this  task  and were guarding  their  nests  from  all
intruders.   The  nests were constructed in water  less  than  12
inches  deep  and closely spaced (the edge of the nests  touching
adjacent  nests).  In the spawning ritual, females  approach  the
males  and  begin  circling each other with fins fully  extended.
After  a short time the pair stops circling and the female  tilts
her   body   to   a  45   angle.   The  eggs  are  released   and
simultaneously fertilized by the male.  The females rarely  spawn
with  only  one male.  They generally move on to other  males  to
complete spawning while the males remain on their nests to  guard
the eggs.

Throughout  the summer of 1992 I collected several green  sunfish
for  my aquarium.  Some had to be returned to their original body
of  water due to conflicts with the other sunfish already in  the
tank.   Eventually I was able to collect two individuals  of  the
same size that got along with minimal fighting.  A third juvenile
green sunfish and brown bullhead catfish, about the same size  of
the   others,  found  in  a  local  pet  shop  were  also  added.
Amazingly, all four fish got along.  Being juveniles I had no way
of accurately sexing the sunfish, but I hoped that I had captured
a pair.  In Pennsylvania, my understanding is that Sunfish can be
legally  collected with a fishing rod and valid fishing  license.
Instead  of  taking  them home to fillet, they  accidently  found
their  way  into  my aquarium.  As long as the fish  are  cleanly
hooked  in the mouth, they suffer no ill effects and are  feeding
by the first or second day.

I maintained the fish all summer in a "community" style 20 gallon
high  aquarium in my outdoor shed.  The shed is equipped  with  a
thermostatically controlled exhaust fan to prevent heat buildups.
The average summer temperature of the aquarium water was about 80
F  with  a pH of 7.0.  No other attempts to alter water chemistry
were  made.  Filtration was provided by a Fluval 3 internal power
filter connected to a spray bar and a Penn-Plax Clear-Free corner
filter  (Model  CF-1).  Drift wood, small  rocks,  a  flower  pot
turned  on  its side and about an inch and a half of gravel  were
provided  along  with  the aquatic plants Vallisneria,  Ludwigia,
Sagittaria, Bacopa and Elodea (Anacharis). Anacharis  grows  wild
in  the  waters  where  I  caught the  sunfish.   The  plants  do
moderately well in the summer, but really thrive and grow quickly
in  the winter when the water temperature is below 50 F. The tank
is  enclosed  in a plywood box with removable lid insulated  with
styrofoam. An air space of about 4 inches surrounds the sides and
top  of  the tank.  Minimal heating is provided using  a  voltage
regulator connected to heat tape.  The heat given off by the heat
tape  warms the air space.  This warm air is pumped into the tank
by  the air pump and effectively prevents freezing or major drops
in  temperature.  The heat is manually controlled and  used  only
when excessively cold.

In  the  summer the sunfish are fed moderately heavy every second
or third day and in the winter 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 slowing 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 include fresh frozen mummichogs, grass  shrimp
and  Atlantic silversides, grasshoppers, crickets, nightcrawlers,
chicken  heart, freeze dried krill, freeze dried daphnia,  freeze
dried  shrimp,  dry cichlid pellets and any other  insect  I  can
catch. The Mummichogs, grass shrimp and Atlantic silversides were
caught with a minnow trap and net while vacationing at the beach.
These  foods  are their staple winter diet when the regular  live
foods are not available.

There  are  no provisions to chill the water in the summer.   The
endure  an  average summer temperature of 80  F  and  an  average
winter  temperature of about 40 F.  Forty percent  water  changes
are   generally  made  once a week in the  spring  and  fall  but
usually every few days in the summer.  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 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  as
the  water in the aquarium or temperature shock to the fish  will

This group of fish were overwintered as naturally as possible  in
the hope that they will be properly cold conditioned and ready to
spawn  in  the  spring.   As soon as the weather  began  to  warm
another  20  gallon high spawning tank was set up  in  the  shed.
Except  for the gravel and sponge filter the tank was kept  bare.
A  chiller  unit was utilized to maintain an optimum  temperature
(70 F) for spawning and raising fry during the hot summer months.
In  April, 1993 as the water temperature slowly increased two  of
the  sunfish  began to swell with eggs but the remaining  sunfish
did not exhibit any male behavior or female egg development.   By
the  end  of  June,  1993 nothing had changed and  I  decided  to
release  that  fish to its native waters and attempt  to  capture
another  fish in the hope I could find a male.  Fishing was  poor
the  day  I  went out and was only able to catch one  beautifully
colored  juvenile  green  sunfish.   I  was  hoping  its   bright
coloration meant it was a male because none of the other  fish  I
captured  showed such color.  As the fish matured (he  more  than
doubled  his size in three months) I realized it was a  male  and
hoped it could be induced to build a nest and spawn.

October  approached  and by this time I was  becoming  frustrated
because I had already put a year and a half of effort and alot of
money  into  this experiment and did not want to wait  till  next
spring  to  see if spawning would occur.  November began  and  no
interest  to  spawn  was  shown by the fish.   The  beginning  of
November  was  warmer  than normal and  the  temperature  in  the
community  sunfish tank spiked about 8 F in a short time  period.
The  male  sunfish began excavating gravel in all  areas  of  the
community  tank.   When  male sunfish are ready  to  spawn  their
colors intensify, they excavate a nest in the gravel and await  a
receptive  female.  Even though the male sunfish appeared  to  be
excavating  a  nest  and I noted his colors  were  brighter  than
normal I paid no attention to what he was up to.  On November 15,
1993  I  checked on them at 10 PM and every thing  seemed  as  it
should.   However, when I went out to check on them at 10  AM  on
November 16, the male was stationed in the middle of the nest and
had  all the other fish pinned in the opposite corner of the tank
and  would not let any of them out.  I thought this odd  behavior
but  I still had not realized what had occurred.  I looked at the
larger  female who the night before was loaded with eggs and  saw
that  she was as thin as a rail.  When I quickly looked  back  at
the male I noticed eggs, hundreds of eggs.  They had spawned over
night and the male was protecting the eggs.  The fertilized  eggs
are  adhesive, perfectly round, colorless and approximately  1/16
of an inch in diameter.

I  quickly removed all the fish except the male and put  them  in
the  spawning  tank.  The spawning female was a bit  ragged  with
torn  fins and the other fish were all in good shape.  The fluval
filter and spray bar were removed and replaced with an air driven
sponge  filter to ensure that none of the eggs or  fry  would  be
sucked  into  the filter.  Air flow was high enough  to  cause  a
light  current in the aquarium.  The current prevents any harmful
material  from settling on the eggs and wigglers.   A  25%  water
change  was  also made.  The community tank was not intended  for
spawning and was in need of a change anyway.

On November 17 I noticed that any eggs kicked up by the male were
quickly  eaten  so I took him out and put him in with  the  other
fish.   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
sunfish  eggs  hatch in 3-5 days at 80 F and  quicker  at  cooler
temperatures.  On November 19 the eggs finally hatched.  It  only
took  3  days  at a water temperature of 65 F and a  pH  of  7.0.
There   were  no  apparent  problems  with  bacterial  or  fungal
infestations  of the eggs as evidenced the large number  of  eggs
that hatched.  With a little care and the heat tape turned way up
I was able to maintain the tank to within plus or minus 2 F of 65
F  to ensure proper incubation of the eggs and development of the
wigglers into fry.  The wigglers were entirely clear, no  visible
markings could be seen.  Within 24 hours (November 20) eye  spots
became apparent and the wigglers started to take the form of fish
24  hours  after  that  (November 21).   Fifteen  to  twenty-five
percent water changes are made every day and so far all is well.

With  regard to how long it takes for the wigglers to become free
swimming my references estimate about one week.  On November 25 I
noticed  a  few  fry making their first attempts at  swimming  on
their  own.  I offered a very small quantity of brine shrimp  but
none  were  accepted.  No further offerings were made  until  the
27th.   This  was the eighth day since hatching and  dozens  were
free  swimming.  I again offered a very small quantity  of  brine
shrimp  and  for  the first time the fry began feeding.   By  the
ninth  day all were free swimming and 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  because  the  fry   are   somewhat
uncoordinated they 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.

Two  months have passed and the majority of the fry are  now  1/4
inch  or  larger.   The remaining fry number  about  one  to  two
hundred.   The fry that were unable to swim properly and/or  feed
consistently  quickly  died.  At first  several  fry  were  dying
daily,  but now virtually none are dying on a regular  basis.   I
figured  I  lost  about  100  fry to what  I  will  call  natural
selection.  At any rate, their survival is by far better than  it
would  be in their natural habitat.  Due to limited space,  I  am
experiencing  cannibalism of the smaller fry by  the  larger  fry
because  I  am unable to provide the tanks necessary to  separate
out the larger fry as needed.  The fry are still mostly dependent
on  brine  shrimp, but will be weaned off the shrimp as  soon  as
they are large enough and can be persuaded to accept other foods.
Even after two months most of the fry still do not resemble their
parents,  i.e. their pelvic fins are not yet visible (dorsal  and
anal  fins  are  faintly  visible) and  their  bodies  are  still
substantially  transparent.  I will consider them juveniles  when
their body shape and coloration resembles adult sunfish.  This is
expected to occur in the next one to two months.  This experience
has  been  very rewarding and helpful in understanding  the  life
cycle of the Green Sunfish as well as Sunfish in general.  I look
forward  to spring when I hope to experience another spawning  of
the Green Sunfish.