Failure of dieldrin to affect color vision in juvenile mallard ducks

Abstract

COMMUNICATED BY LOUIS LY KKENNine mallard ducks were raised artificially from eggs and fed the same long-term doses of dieldrin as their parents (0, 4, or 10 ppm); in addition, three ducks from 10 ppm parents were raised on 50 ppm. The parents had been on dieldrin-treated feed for two years. The juvenile ducks were tested at approximately two months of age. Each duck was trained to respond (key peck) differentially to light wavelengths of 552 m/.t (S +) and 610 m/2 (S-) and, subsequently, was presented 13 different wavelengths, in random order. Differential responding was analyzed for stimulus generalization. No significant differences (p < .05) were found between the control and treated groups' mean stimulus generalization gradients. Only the group receiving 50 ppm in their feed had a mean whole-brain dieldrin residue significantly larger (p < .05) than that of the control group. These results indicate that the ingestion of dieldrin, under the test conditions used, does not have a measurable effect on light wavelength discrimination in mallard ducks.Recently, interest in the sublethal effects of pesticide chemicals has focused on possible behavioral aberrations which possibly are deleterious to the survival of the individual or population. Ogilvie and Anderson (1965) exposed Atlantic salmon (Satmo satar) to sublethal doses of DDT ranging from 5 to 50 ppb; they found that the fish which received low doses selected colder water while those which received high doses selected warmer water. Warner et al. (1966) demonstrated that toxaphene reduces the ability of several fish species to avoid conditioned shock. Cooke (1972) noted that frog (Rana ternporaria) and toad (Bufo bufo) tadpoles, when exposed to 0.5 ppm of dieldrin in amphibian saline for 24 hours, showed hyperactivity followed by "resigned" behavior. Dieldrin was shown to affect the performance of sheep (Ovis aries) on both a vigilance task (Van Gelder et al. 1969) and a visual discrimination task (Van Gelder et al. 1970). Baxter et al. (1969) found that pheasant chicks (Phasianus colchicus) hatched from eggs laid by hens which had received 8 mg of dieldrin per week chose the deep side of a visual cliff (Tallarico and Farrell 1964) significantly more often that did control chicks. 1present address: