On 13 October 2002, as part of the Year of Clean Water's National Water
Monitoring Day, NANFA members sampled four stream sites in the Bayou Pierre
drainage of western Mississippi. On 05 October 2003, as part of the
data-acquisition effort for World Water Monitoring Day, two of those members,
Tyler Strange (LA) and Jan Hoover (MS) re-sampled those same four sites.
(Click on a thumbnail image to display a larger image)
Lower White Oak Creek at Highway 18 shows pronounced bank erosion. Water was
clearer than last year and pH higher.
Water levels were substantially lower than the previous year creating riffles,
backwaters, and flowing side channels. A large gravel bar was exposed....
....that contained numerous fossils of marine invertebrates....
....including this bryozoan.
Tallahalla Creek, a major tributary to White Oak Creek, was sampled at
Highway 27. Water levels here were also appreciably lower than last year.
Turbidity (opaqueness) of the water was
measured with a turbidimeter. Temperature, pH, and dissolved oxygen were
measured with a Hydrolab multi-parameter water quality probe. Water was
clearer and pH higher than in 2002.
Upper White Oak Creek was sampled at Low
Water Bridge Road. Like the the other sites, water was lower, clearer, and more
alkaline than in the previous year. After recording water quality data, fishes
were collected by seining and a species list compiled. Composition of the fish
community was similar to that of last year: striped, longnose, and blacktail
shiners, harlequin and redfin darters, brindled madtom, and longear. Also
collected (and carefully released) was a single specimen of the endemic and
federally endangered bayou darter.
The tiny, unnamed, springfed tributary to
White Oak Creek was also re-sampled. Water quality and fish community were
similar to those of last year. Effects of flow on dissolved oxygen and fishes
were pronounced. Normally, two small waterfalls provide flow to two pools of
equal size and depth (in the photo - ahead of and on each side of Tyler). Water
level this year, inches lower than usual, provided flow only to one of the
pools. The stagnant pool, with a dissolved oxygen of only 1.37 ppm (< 4 is
considered hypoxic) was inhabited by a single striped shiner. The flowing pool,
with dissolved oxygen of 6.83 ppm, contained several striped shiner and creek
chub, as well as a creek chubsucker, bluegill, longear, and blacktail shiner.
Effects of lower water levels in the Bayou
Pierre drainage on water quality were pronounced demonstrating the need for
repeated and spatially extensive sampling necessary to detect any long-term
changes in water quality. NANFA members have a strong commitment to the
conservation of aquatic resources and a broad geographic distribution. As such,
they are ideally suited to participate in the ongoing efforts of World Water
Monitoring Day to increase public awareness of water issues and to build a
meaningful, volunteer-generated database.
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