Date of Award
Honors College Thesis
David C. Beckett
This survey was conducted at the Lake Thoreau Environmental Center in Hattiesburg, MS. It began with four benthic samples taken in the deep area of the lake as well as four taken in the lake’s shallow area. Samples were taken with a 6”x6” Ekman Grab Sampler and filtered through a U.S. standard 30 mesh sieve (openings = 0.6 mm). The samples were initially stored in formaldehyde for 24 hours, and then transferred into ethanol. In the laboratory, macroinvertebrates were picked out of the samples while viewing the samples through a dissecting microscope. High densities of the phantom midge Chaoborus larvae were found in all four of the deep water samples, along with mites, a few copepods, and an amphipod. Within the shallow water samples there were high densities of oligochaetes (Phylum Annelida). Also present were Heleidae representatives, chironomid larvae, mites, and copepods. Only a few Chaoborus larvae were present in the shallow water samples. The changes in fauna found between the shallow water areas (ca. depth = 1.5 m) and the deep water areas (ca. depth = 4.5 m) are likely the result of anoxic conditions that occur near the bottom of the lake in deep areas during the summer and early fall, and perhaps at other times of the year. In contrast the bottom of the lake in the shallow area always possesses relatively high amounts of oxygen. By distinguishing the fauna in the Lake Thoreau environment one can see how biodiversity and density fluctuate across the lake during at least the fall portion of the year.
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Dobronski, Elizabeth A., "A Survey of Lake Thoreau’s Benthic Invertebrate Community" (2017). Honors Theses. 519.