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~ <;:> ---l Historic data (Tables 10 - 12) show fecal coliform r.rmtb.1y averages ranged ::.l' f~om 18 organisms/loa .~ in February at CR-16 to 10,973 organisms/lOa mU in July at CR-22. Further examination of historic data reveals that the standard deviation The source of the bacteria is unknow.n. variations may exist in numbers oE fecal coliform present at any sampling location. was greater t.~n the mathematical average Over 90% of the time indicating large Bioloaical of the r~ver bottom has not L~'en collected to date. Samples that have been The necessary qU3ntity of benthic samples needed to compare various stretches ccllected indicate different insect communities inhabit different types of river substrate. A diverse group of insect larva inhabited all areas where the River lar~a. In comparison, few organis~, both in species and number, inhabit the provides a rubble substrate; Caddis fly, Mayfly, Stone fly, beetle, and Dipt~ran pore-ions of the river substrate covered b~ sediments. Rocks that were Co~.ered by a tb.in brown sediment during the Fall provided suitable habitat for caddis flies of the family Hydropsychidae and mayflies of the genus Tricoryt.ia.des sp. Ever. fewer organisms, both in species and numbers, inlJ.3iJit the dense m:Jck found on the river substrate. One species of caddis fly (PhilCpctamidaeJ r.ct feund elsewhere in the River and two mayfly species, Thraulodes sp. and Cyni~ sp. -15- were found on the muck-covered rocks down to the dept.h where the muck turned black. The odoriferous black muck appeared to prOvide a suitable hdbitat Eor only two species oE C.llrono;r:idae (blood wor:~) Dipteran larvae. Both species possess a hemoglobin type blood, indicating a possible preference Eor an oXl;F;en poor er Oxygen lacki."'lg environment.