USE OF THE CHEMOSTERILANT ORNITROL IN FERAL PIGEON (\u3ci\u3eCOLUMBA LIVIA\u3c/i\u3e) CONTROL

The chemosterilant ornitrol was tested as a means of reducing egg production in feral pigeons on the central campus of Bowling Green State University. Ornitrol (0.1 % by weight), coated on whole-kernel corn, was baited on building rooftops for 1 O-day periods in 1982 and 1983. Weekly post-treatment nest monitoring indicated that ornitrol does not inhibit egg-laying, but 16-29% of all eggs laid were infertile. This increase in egg infertility over the pre-treatment period was significant. However, because pigeons breed throughout the year on campus, it is estimated that this reduction in productivity would have no major impact on the population. A limited laboratory trial indicated that pigeons feeding on untreated corn ate significantly more food than did treated birds. Egg-laying was inhibited in two of three pairs treated for 10 days and was nearly complete in three pairs treated for 20 days. However, pigeons in the 20-day group became lethargic, and one bird died after treatment. It appears that the chemical, at an average dosage of 0.3 g chemosterilant per bird, acted more as a debilitating agent than as a sterilant. The present ornitrol formulation cannot be recommended for use in pigeon control