Proceedings of the Vertebrate Pest Conference

Recognition of a gene in Norway rats, a result of mutation, that produces male sterility linked to white pelage on the head or abdomen, has been studied at the University of Oklahoma. At the age of 120 days, mutant males show no spermatogenic activity. In a controlled laboratory test situation, use of sterile males has been demonstrated to reduce population growth. Results from subsequent fields tests conducted thus far do not allow us to say that the Norway rat can be eradicated by introduction of sterile males; we do not yet have an adequate basis for devising a formula for release rates of sterile males. In future research, other heritable characters may be discovered that can be combined with the sterility gene to improve the sterile males’ competitive performance.