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Elassoma
evergladei: Dwarf Pygmy Sunfish
Sallie
Boggs
GPASI
Journal , Fall
1985
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For
several years I have wanted to obtain some Elassoma evergladei
and made my desire known to friends in Madison, Wisconsin, where I
spent ten delightful months on sabbatical leave. I had heard that
these little fish, ranging in nature from North Carolina to Florida,
were real gems in the aquarium. Much to my surprise and joy, Rick
Ivak presented me with an adult pair as a going away present when
I left Madison in November '84.
Small fish that mature at one inch to one and a half inches, the E.
evergladei reportedly can survive temperatures from freezing
to just under 80 degrees F. At spawning time, the male is a velvet
black with numerous shining turquoise scales scattered in the black,
and the female is golden to reddish with intermixed shining gold scales.
When they are frightened, both sexes can take on a drab, mottled color
pattern that makes them almost invisible in a natural aquarium. Their
"invisibility" is compounded by their habit of staying motionless
at odd angles.
Although they undoubtedly would prefer an outdoor pond, they can live
apparently happily in a small tank. Another Madison friend, Matt Hirvonen,
had a pair that spawned in a five-gallon tank, so I placed mine in
a "5" and added an overdose of live daphnia. This kept them
fed and the tank clean while I finished packing up for a two-day car
trip back to Pittsburgh.
When the car was stuffed to the gills with clothing, boxes, and fish
tanks, I set off, the E. evergladei snug in their bags in
a styrofoam box in the back of the car. As the trip progressed, temperatures
dropped, and when we arrived in Pittsburgh the next day, I took the
fish to the only place where I knew of an available tank, Ed Redgate's
laboratory at the University of Pittsburgh. When I arrived with my
chilly fish, Ed seemed unimpressed by the evergladei. Even
I had to admit that they looked rather plain and somewhat shaken.
In order to make them feel at home, we set them up in a five-gallon
tank on the window sill, with a three-inch-thick block of styrofoam
to shield them from direct sun. The cold metal window sill would keep
them cool.
The tank was decorated with floating plants and plants rooted in 1
to 2 inches of brown sand (fine gravel). A few chunks of petrified
wood provided shelter, which they seemed to appreciate. There was
no filtration, air, or heater provided. Livebearing snails were added
to keep the sand clean, and ramshorn snails to keep down the algae
and clean up excess food. The fish at first were seldom seen except
at feeding time, but they seemed to thrive, even though their water
temperature dropped low into the 50s in January and February.
Although the fish ate flake food, they seemed to hate it. They really
perked up when the ponds thawed and daphnia and ice worms were available.
They had a curious way of eating. The fish would sit motionless in
the water until a daphnia came near; then it snapped it up with a
sideward motion of its head. The combination of live food, lengthening
light periods, and warming temperatures seemed to bring on spawning
condition, and the female began to fill with eggs. The male turned
black and started following the female around the tank, flirting with
her. In trying to attract the female, he went through some really
exaggerated gyrations of body and fins. He waved his dorsal fin in
rapid rhythm, made back and forth body movements and alternate backward
and forward "walking" movements of ventral fins. The female
often assumed a head-up, tail-down stance.
All of this prespawning ritual went on for the months of March, April,
May, and June. Although I never saw an actual spawning, I did see
small numbers of larval fish about 1 mm long, hanging from tank walls
and furnishings. These took several days to become free swimming.
When they did, they disappeared among the floating plants and swam
in rapid dashes followed by sitting motionless. The young were very
shy and were all but invisible. Some survived and grew up in the tank.
Others were fished out, and fed on sponge grunge and green water.
Later, they ate live baby brine shrimp. They grew slowly, but seemed
hardy. All fry were colored similarly to the female.
By July, all the E. evergladei had been put out in my pond,
and by the end of July the young were half grown. The males were already
beginning to show darker coloration.
There are several descriptions in the literature of the spawning of
this species. Reference 1 says that they are not nest builders; that
their eggs are attached to plants and other objects. They spawn many
times at two-week intervals, with a few eggs at a time. They reportedly
spawn in late spring and early summer and post-season eggs are not
released but are reabsorbed. Conditioning depends on the speed of
the increase in temperature. They are said to hibernate at <10
degrees C, in deep water, and to spawn in warmer water.
Reference 2 tells where they were found and says they prefer quiet,
well vegetated waters, and eggs are laid on aquatic vegetation. The
egg incubation time is 65 hours at 25.5 degrees C. There are 25-30
eggs, and fry eat copepods in nature.
These fish have endearing ways and are so attractive that they remain
my favorites even though I have already bred them. They have convinced
me to have a cold water fish room for native fish.
References
1. Breder, C.M., and Rosen, D.E., Editors, Modes of Reproduction
in Fishes: How Fishes Breed. TFH. Pages 425-426.
2. Lee,et al, Editors; Atlas of North American Freshwater Fishes.
No. Carolina Biol. Survey, New York State Museum of Nat History, 1980-12,
page 584. |
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