Technical Abstract: The Carl Hayden Bee Research Center is located near the northern edge of the Sonoran Desert and had been studying feral bee colonies in rock cavities. Locating and documenting the local feral bees began in 1987 and by 1991 we were recording information on 241 nest sites. Two hundred and sixteen of these feral colonies were sampled and initially they were genetically identified as European although 3 colonies had mitochondrial DNA from a mother line that was from N. Africa. In 1995, 2 years after they were first found in Tucson, the Africanized honey bee began swarming into the study area. Beginning about 1990, tracheal mites and then in 1995, Varroa mites infested, and then decimated, colonies in our study area. In 1998 the feral populations were reduced to 5% of their original numbers. They are now, in a "good" year, back to 48-50% occupation. Low levels (~7%) of Varroa mites were still found in most colonies. In this report, we present the GPS data for one representative colony at each of the locations.