ALBUQUERQUE, N.M. -- It's back to captivity for a pair of Mexican gray wolves that federal wildlife managers had planned to release in Arizona's Apache National Forest.
The U.S. Fish and Wildlife Service announced Wednesday that the male and female wolves will not be released.
The pair had been transported from a captive breeding facility in New Mexico to southeastern Arizona in late April. The wolves have spent the last six weeks in a temporary pen so they could acclimate to their new surroundings.
Officials say the female was pregnant at the time of the relocation but the pups did not survive.
Another pack of wild wolves also acted aggressively toward the pair, suggesting that the release might prompt a battle over territory.
Officials say they will look for another opportunity to release the pair.