Band-tailed Pigeon (IMAGE) University of California - Davis Caption Three band-tailed pigeons perch in Santa Barbara County. Researchers at UC Davis and the California Department of Fish and Wildlife have identified trichomonosis as a key factor in winter die-offs and the population decline of this native migratory game bird. Credit Courtesy Dianne Ricky Usage Restrictions Provide credit. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.