Clinostomum marginatum (Yellow Grub) Metacercaria in Black Bass from the Caddo River in West Arkansas

Seventy-two bass (Micropterus-spp.), mostly smallmouth, were collected from three areas of the Caddo River in west Arkansas and examined for the presence of Clinostomum marginatum metacercariae. Prevalence, mean abundance, and abundance for all fish were 68%, and 4.2 ±6.5, and 30, respectively. Fish from the upstream area near the headwaters were more heavily infested than those from further downstream. Agill/total body larval ratio of seven, was found for bass from another Arkansas stream, was examined as a predictor for total Clinostomum populations in stream bass. Using the formula gillparasites X seven divided by N (72), a value of 3.3 was found for mean abundance. The gill/total body ratio for Caddo bass was found to be higher at 8.9 but the ratio of 7 gives a reasonable estimate of Clinostomum burdens in a stream bass population. Use of this ratio allows bass hosts to be examined without necropsy thus preserving the host population in its environment.