
Spawning the Pumpkinseed Sunfish (Lepomis gibbosus)
By Joanne Bockstael
reprinted from American Currents, June 1984
We, as aquarium hobbyists living in Canada and the United States, are really very
lucky, for within the boundaries of continental North America is to be found a vast wealth
of fish (and other aquatic) life. We have an incredible number of fish species of which we
can boast, but among them is one species which we rarely mention. This fish is the humble Lepomis
gibbosus, the Pumpkinseed Sunfish.
The Pumpkinseed is one of the commonest sunfish. Perhaps it is because of this that we
tend to overlook or ignore it, and in doing so we are doing the Pumpkinseed and ourselves
a great disservice. In general appearance, Pumpkinseeds present a typically cichlid-like
profile and are quite colorful even outside the spawning season. The Pumpkinseed's basic
ground color is a dull greenish-gray with darker vertical bars. This is overlaid by a
yellowish to orange cast which deepens in hue on the belly. The eyes are red with a black
pupil which is bisected by a black bar, The head region is decorated by several dark,
more-or-less horizontal bars which are separated by light "electric-blue"
zigzagging lines which extend to the edge of the operculum. The operculum is decorated by
a "Sunspot," a prominent black spot edged in red around part of its
circumference. The Pumpkinseed is further decorated by numerous red dots over its body and
flanks. These may extend in a vague checkerboard pattern into some of the fins, though
this seems to be a regional characteristic, and is totally absent in specimens from many
areas. (I mention it since my own Pumpkinseeds do show a strong pattern of red dots on
most of their fins, while individuals I have seen which were collected from an area less
than 400 miles from where I live showed no red whatsoever on the fins and only a sparse
scattering of red dots on the upper part of their bodies.)
If collecting for the home aquarium, it is best to start with young Pumpkinseeds less
than 4" in total length. They must have plenty of space in their new home, as these
fish will reach a total length of some 8-10" at maturity and will be far less
belligerent when fully grown if they haven't been overcrowded from the start. I found I
got the best results if I kept no more than six fish in a tank of not less than 40
gallons. The tank I used was equipped with an undergravel filter while the young fish were
growing, but as they matured they began to show a very cichlid-like habit of
"redecorating" their tank. The U.G. filter was then replaced by two DynaFlo 150
power filters. The gravel I used was a mixture of a nearly fine grade of crashed dolomite
in a dark gray color and a coarse grade of "roadside" gravel (a mix of granite
and slate commonly used -in road-bed construction in Canada). A couple of pieces of
driftwood and several large rocks (granite mainly) completed the decorations. Plastic
plants may be used, but live plants really take a beating. Be sure to leave a few large
open areas for swimming, as sunfishes (of any species) are not prone to hide. Also, they
will need these spaces later for spawning. Pumpkinseeds are not fussy when it comes to the
water in their tank, but they cannot tolerate dirty water for long. As coldwater fish,
they need more oxygen than small tropicals, so be certain your filtering system is
adequate and always working well. The pH of their water should be alkaline, but with
regular water changes and no sudden drastic moves by your local water company, they will
adapt themselves to anything from 6.7 to 8.2; however, extremes should be avoided.
Pumpkinseeds are heavy eaters and need even more than usual if they are to spawn. I
feed mine on raw beefheart which has been mixed with flake food, oatmeal (small amount, as
it clouds your water when there's too much; use not more than one cup to two pounds of
meat), some unflavored Knox gelatin, and (if I can get lots, as in summer or fall) nearly
as many earthworms by weight as I have of the beefheart. This mixture is put through a
blender (do not blend to a fine texture; leave the meat in small bits!), then packed in
thin layers (up to 1/2") in freezer "'Zip-loc" bags and frozen. I need only
break off what I need in small chunks and feed directly into the tank. The gelatin will
help hold the food in lumps from which the fish can easily bite mouthfuls, which makes
removing the leftovers much easier. I feed as much of this plus frequent meals of chopped
earthworms as the fish will eat in five to ten minutes, as often as four to six times
daily. These are fish which can really eat!
To bring these (like most) native fish into spawning, it is necessary for them to go
through a "cooling period." I am lucky in that my bedroom is quite cool all
winter (due to drafts) and cool in summer too (thanks to an air conditioner). It is here
that I keep whatever natives I have. Beginning at any time of year, I either open the door
to a balcony or hike up the air conditioner so that the room and the fish are chilled for
a few hours a day until I can't tolerate the cold any longer!). Gradually over a few
weeks, they are chilled, then warmed, over and over, every day. Simultaneously, the length
of time the tank lights are kept on is gradually increased from 10 to 14 hours a day. With
heavy feeding, it isn't long before the fish come up to spawning condition and begin to
think of setting up housekeeping,
If all goes well, once your fish are from six to eight inches in length, they should
begin pairing off. The males will show a much deeper orange on the belly and they will set
up territories within the confines of the tank. (Having lots of room at this stage will
keep the scrapping down to a minimum, and these fish can and do fight hard!) The females
will definitely look and be heavier in the ventral area, and they will tend to keep near a
central point such as a piece of driftwood more or less in the middle of the territories.
Unless you have several large tanks prepared in advance, it is best at this stage to
remove all but one pair (or trio) from the aquarium. More than one male, and few if any
fry will be produced, as the males will fight with each other and with the females. Extra
pairs can be kept apart (permanently) or given away.
For a time, the male will flirt with his mate(s). Between such bouts, he will choose an
open area of tank bottom, and, using his tail, will dig a fair-sized pit (hence the need
for room). Fairly fine gravel is necessary, first of all so that the male does not
lacerate his tail while "digging," and also, if the gravel is too coarse, the
male will become discouraged and no spawning will occur. Once the pit is ready, the female
is nudged over to it, and, with the fish side by side, the eggs are laid and fertilized.
When spawning is completed (often with more than one female), she (they) should be removed
or she (they) will be at risk of being killed. Her (their) part is over and her (their)
continued presence serves no purpose. For two or three days until the eggs hatch, the male
will guard the pit, fanning and often even mouthing the eggs. Once the eggs have hatched,
though, the male should also be removed, You can try feeding the male while he is "on
guard," but usually the male will not eat, and you just run the risk of polluting the
tank. I would suggest you not have an undergravel filter in a spawning tank because of
their method of spawning. When a spawning seems imminent, you should shut off power
filters and substitute a couple of sponge filters run by a strong pump.
The fry of the Pumpkinseed Sunfish will thrive on a diet of newly hatched brine shrimp
nauplii right from the start. After a week or so, microworms can be added. Soon after
this, feedings of the adult diet "blenderized" to a very fine grade can begin.
The fry grow rapidly. From one female of 7-8", you can expect to get at least 300
eggs. Likely, it will be 500 or even more if your breeders have been well conditioned and
are two or three years old or older. Most of these eggs will hatch and the fry will
survive, so that a roomy tank (or tanks) is necessary.
How many people want Pumpkinseeds? More people should, as they are great fish--easy to
keep and to spawn. And not everyone has them.
Used with permission. Article copyright retained by author.
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