Water-bait Egyptian fruit-bat Rousettus aegyptiacus α-chlorohydrin antifertility controlThe Egyptian fruit-bat (Rousettus aegyptiacus) is a serious vertebrate pest that lives in riverine and agricultural habitats of the Nile Delta and Valley of Egypt. The present work evaluates the acceptability and effect of a water bait of α-chlorohydrin (ACH), which is a well-known species-specific male chemosterilant, on the fertility of males of this bat species. A dose of 85.7mg/kg consumed by captive males for four consecutive days has damaged their testicular tissues, caused a significant decrease in sperm count and motility and a significant increase in sperm abnormalities. Preliminary results of the study of the reproductive cycle of this bat species in one of the districts of Greater Cairo Area showed that males had reached peak sexual activity during autumn mouths. For best control results, it is suggested that control campaigns be implemented during these months. It is recommended that ACH water-baits be set in roosting caves and near fresh water courses where bats used to drink.