The 7-day LC50 of chlordimeform to bobwhite (Colinus virginianus) chicks was 2835 ppm (95% CI = 2169-3705 ppm). Bobwhite chicks fed 1000 ppm (~ LC4) chlordimeform for 7 days ate less, weighed less, travelled farther from a fright stimulus in an avoidance test, and had significantly more groups make >10 light beam interruptions in an open-field test at 8 days of age than bobwhite fed 0, 1, 10, or 100 ppm chlordimeform (P< 0.05). Groups fed 100 ppm (P <0.05) and 1000 ppm (P = 0.11) for 7 days crossed more often from the shallow to deep side of a visual cliff at 8 days of age than birds fed lesser concentrations of chlordimeform. Bobwhites were retested at 15 days of age, after being fed untreated diets for 7 days following the chlordimeform diets. The 1000 ppm group still travelled greater distances in the avoidance test (P < 0.05). But open-field and visual cliff performances were similar to controls and other treatment groups. Chlordimeform concentrations causing behavioral abberations in bobwhite were appreciably higher than environmental concentrations following field applications of chlordimeform.
