Philip K. Evans

Transects established to measure whitewing nesting success have revealed that doves are subject to heavy (50-75 percent of the eggs laid) nesting predation. Prior research (Blankinship's study in 1964-1965) has indicated that whitewing (Zenaida asiatica) production can be increased 100 percent if boat-tailed grackle (Cassidix mexicanus) numbers are controlled during the nesting season. This project was initiated in the Lower Rio Grande Valley of Texas in 1967 to determine the effects of grackle control on white-winged dove and grackle nesting success. Work with poisons as a grackle...

A ten-year study of the reaction and adaptability of the introduced Aoudad sheep (Ammotragus lervia) in the Palo Duro Canyon of Texas was begun in the winter of 1957-58. At that time, forty-two sheep from the McKnight Ranch, Picacho, New Mexico, were released into the halfmillion acre Palo Duro Canyon. The exotic sheep were introduced into the canyon to fill a separate ecological niche and to share the vast reaches of the canyon, noncompetitively, with native mule deer. The aoudad, a hardy big game animal, was to become a real challenge to sportsmen in the rugged terrain of the Palo...