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Saving the
Longeared Sunfish
By Fred
Hamilton
Sunfish are members of the
family Centrarchidae -- the ecological equivalent of the
cichlids, which belong to the family Cichlidae. The most
familiar of all game fish, the Bluegill, Lepomis macrochirus,
is a sunfish. Locally, we are fortunate to have one of the most
beautiful representatives of the family, the longeared sunfish, Lepomis
megalotis (Fig. 1). This article relates my experiences in
keeping and breeding this beautiful fish, and how I came to make an
effort to conserve this species (and the pumpkinseed sunfish, Lepomis
gibbosus ) (Fig. 2) with the help of the Cleveland Metropark
Zoo.
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Fig. 1. Longeared
Sunfish, Lepomis megalotis

Fig. 2. Pumpkinseed
sunfish, Lepomis gibbosus
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Unfortunately, the longeared sunfish is an endangered species over
much of its former range. It is officially listed as
"threatened" in Wisconsin, Pennsylvania, and New York, and
as a "Species of Concern" in North Carolina. Illinois
populations have been recognized as being in decline since 1979, and
the species is become extinct in Iowa. The Ohio Department of
Natural Resources website notes significant threats to the species
caused by habitat destruction in western Ohio. As a result of these
and similar pressures, the longeared sunfish is now absent from all
of southwestern Ohio, except for two populations in Clermont County,
one at scattered points in the Little Miami River, and another in a
tributary of the Ohio near the Moscow, Ohio Zimmer power plant. I
have collected young fish from each of these populations, and around
Christmas, 1997, a pair finally spawned.
Longears are typical of members of the genus Lepomis, and
breed in nests formed by the males, which fan a depression in gravel
by standing upright, using their tails as a "broom."
Groups of transparent adhesive eggs (typically 100-300 in captivity)
are expelled by the female who is literally pressed to the substrate
by the amorous male. After spawning, the female is driven away:
after the fry become free-swimming, the male also loses interest.
Fig. 3 shows the male enticing a female into a nest created in a
terra-cotta flowerpot base. Fig. 4 shows the young at about three
years. The size variation between young male and female longeared
sunfish is dramatic: Fig. 4 shows a young adult male of about four
inches TL, surrounded by smaller females ranging in size from
1" to 2.5".
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Fig. 3: Romance in Longeared
Sunfish

Fig. 4: Three-year-old Fry
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Raising newborn sunfish is difficult -- but only for the first month
or so. Fry must be fed newly-hatched brine shrimp during this
period, but thereafter will eat virtually anything you care to feed
them, including flake food, trout chow, worms, mosquito larvae, and
especially frozen brine shrimp. My first spawn was raised in a
55-gallon, then a 125 gallon, and finally, in a 1,000 gallon
concrete tank (an article about the 1,000 gallon tanks appears
elsewhere at this site). Below (Fig.5) is a photo of the
"grow-out" tank containing about 200 longears which
survived to three years of age.
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Fig. 5: Thousand
Gallon Grow-out Tank
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Word of these fish spread around the internet, and with the help of
the North American Native Fishes Association's mailing list, I was
able to share about 50 fry with collectors in Idaho, Florida, and
Ohio.
In September, 2000, I received an e-mail from Nick Zarlinga, an
Aquarium Biologist at the Cleveland Metropark Zoo, inquiring about
the possibility of obtaining longears and pumpkinseed sunfish for a
65,000 gallon outdoor display (with underwater viewing window).
Needless to say, I was thrilled (and relieved -- note that 200
longears eat a lot of frozen brine shrimp!). So, one
Saturday, a van from the Zoo, with the Zoo's Curator Don Kuenzer,
arrived at the door of my fishroom in Kennedy Heights (Fig. 6-7).
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Fig. 6. Don Kuenzer
(Left) and me (in Volunteer Uniform)

Fig. 7. Zoo Logo on
"Fishmobile"
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The prior day, I had removed one ton of creekstone from the 1,000
gallon tank (Fig. 8). This simplified the capture of 75 longears of
a suitable size for display and their transfer into the van, which
was equipped with two transport tanks of about 200 gallon capacity,
and electrically-powered air pumps (Fig. 9).
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Fig. 8. One Ton of
Cincinnati Rock from Grow-out Tank

Fig. 9. Sump Pump
Transferring Shipping Water
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After a brief cooperative effort by me and Don, the first batch of
three-year-old longears were ready for shipment (Fig. 10). A second
effort netted eight assorted-size Pumpkinseed sunfish obtained from
an Idaho breeder -- also destined for the Zoo's display (Fig. 11).
Fig. 10: 3 year olds -
ready to ship, Lepomis megalotis

Fig. 11: Yearling
Pumpkinseed, L. gibbosus
I have worked with many species of fish,
but the longeared sunfish is probably one of the easiest -- and
certainly one of the most beautiful -- species which I've had the
pleasure to know. More importantly, it is one of many native species
which need our our attention and our help in order to survive in the
new millenium. Hopefully, thanks to efforts of Nick, Don and the
staff of the Cleveland Zoo, the public will become more aware of
this endangered "hidden gem" which graces our local
waterways.
Interested in educational efforts aimed
at safeguarding our aquatic resources?
The Wave Foundation at the Newport Aquarium is accepting
applications for volunteer educators.
Call Jenny Yee, Volunteer Coordinator, at (606) 815-1441
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