Brett
Albanese, Lucas Hix, and Chris Yator from Georgia Department of Natural
Resources and Evan Collins of TNACI.
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Last
week TNACI biologists Bernie Kuhajda and Evan Collins met Georgia Department of
Natural Resources biologists Brett Albanese, Lucas Hix, and Chris Yator on the Cahaba
River in Alabama in search of federally threatened Goldline Darters (Percina aurolineata); this species gets
its name from the gold line above the black blotches along its side. It is
endemic to the Mobile Basin and is restricted to the Cahaba River in central
Alabama and the Coosawattee River in northern Georgia. The study is looking for
genetic differences between the Alabama and Georgia populations of this very
rare fish. A small piece of fin tissue was removed from each specimen that will
be used for genetic analysis by professor Steve Powers at Roanoke College in
Virginia. The group was able to catch 56 Goldline Darters from 8 localities,
most in shallow water flowing over gravel and larger rock (cobble). Forty
additional fish species were also collected; the Cahaba River is the most
diverse river for its size in the United States, with 130 species of fishes
recorded.
Goldline Darters (Percina aurolineata) with the lower specimen showing the gold line above lateral blotches. These six were all collected in one seine haul! |
Collecting
for Goldline Darters in the Cahaba River at Piper and in Schultz Creek.
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Our
first site was the Cahaba River in the town of Centreville, where 34 species of
fishes were collected, including several Goldline Darters. This site is very diverse for fishes as it sits
on the Fall Line, an area that separates the upland to the north (Valley and
Ridge province) with the lowlands the south (Coastal Plain province) and
therefore has both upland and lowland fish species. This is the most downstream
site for Goldline Darters. Other fishes collected are shown below.
Male
Greenbreast (above) and Rock Darters (below) (Etheostoma
jordani and E. rupestre) found in
shallow fast water with gravel and larger rocks.
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Nuptial
male Tricolored Shiner (Cyprinella
trichroistia)
with breeding
tubercles on top of head and snout.
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We
collected Goldline Darters upstream in the Cahaba River proper at four other
sites with the most individuals (20) collected near Helena approximately 40
miles upstream from Centreville. We tried to get Goldline Darters from their
most upstream site in the Cahaba (another 8 miles upstream from Helena) but
were unsuccessful.
Goldline
Darters were also found in all tributaries where they are known from, including
Schultz and Shades creeks and the Little Cahaba River. The largest population
is in Shades Creek (13 specimens collected), which was just discovered in 2006
along with federally endangered Cahaba Shiners (Notropis cahabae). Before this discovery Shades Creek had been
considered polluted and only a few tolerant fish species were known from
upstream localities.
Updates on the results of the genetics study will be posted when available!
We caught this Alabama Map Turtle making a nest and laying eggs. Very cool! |
Shades Creek site was just discovered in 2006 to have Goldline Darters as well as Cahaba Shiners! |
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