Summer and winter transects were run throughout the range of the red wolf (Canis rufus) along the Texas Gulf Coast utilizing a handcranked siren to elicit howling. The red wolf could be distinguished from the coyote (C. latram) by its patterns of vocalization. Slight confusion was caused by wolves which, located close to the siren barked like domestic dogs. No significant differences were detected between the effectiveness of the technique in winter or summer or between two or four-mile spacings of the howling posts along transects. Heavy fog did cause a significant decrease in the number of responses and high winds probably limited the effectiveness of the technique. Many areas thought to be occupied by red wolves were found to contain only coyotes. The coyote appears to be expanding its range into the marshes and coastal prairies which are the last stronghold of the red wolf. Isolated wolf populations were located in Harris and Brazoria Counties along with the major population grouping in Liberty, Chambers and Jefferson Counties. Highest densities of wolves are found on the prairie. There appears to be no genetic linkage between Texas and Louisiana populations because of a canid-free zone surrounding Lake Sabine. Populations of wolves appear to be rapidly disappearing and without rapid protection and aid it is likely that the species will become extinct in the wild within the decade.
