Analysis of Piebald Madtom (Noturus gladiator) diet

Abstract

The Piebald Madtom, Noturus gladiator, is found in tributaries of the Mississippi River from the Obion River in northern Tennessee to the Big Black River in central Mississippi. The species is currently petitioned for listing under the federal Endangered Species Act of 1973, and is of conservation concern in both Mississippi and Tennessee. Yet little is known about the feeding ecology of the species. To this end, diets were extracted from stomachs and intestinal tracts from available formalin-preserved museum specimens (n = 57). These specimens came from the Hatchie River, Wolf River, Yazoo River, and Big Black River of Mississippi or Tennessee. All diet items were identified to the lowest possible taxonomic level, and contribution characterized as percent composition by number, total number of prey items, proportion of diets containing a prey item, frequency of occurrence, and prey-specific abundance. Twenty-one different diet items included larval trichopterans with sand cases, teleost scales, ostracods, and larval odonates (primarily Macromiidae). The relationship between prey-specific abundance and frequency of occurrence was described using an Amundsen plot, and revealed that trichopteran larvae and larval odonates are of high importance, and suggesting the species may forages on both sandy substrates and leaf packs.