The Mountain Lion dietary supplementation program

Arizona Game & Fish Department is reintroducing Bighorn Sheep to the northern Santa Catalina Mountains in an effort to restore a population which died out in the 1990s.

Joe Sacco of AZGF gave an update to an audience of docents at the Arizona-Sonora Desert Museum on March 5, 2014. He was joined by Dr. William Shaw of the University of Arizona.

Of the 31 Bighorn Sheep introduced last November, 15 have died: 13 were killed by mountain lions, one by a bobcat, and one died from the stress of relocation. AZGF will do two more phases of the program, each introducing an additional 30 Bighorns over the next two years. Sacco says the program is not supported by tax dollars, but by donations, especially by hunting groups. The purpose of the program, according to Sacco, is to restore the natural diversity of the area.

The Bighorn population of the Santa Catalinas began dropping drastically in 1986. AZGF admits that it does not know why, but offers these possible reasons:

Urban encroachment;
Recreational stress, i.e., hikers or hunters with dogs stressed out the Bighorns;
Habitat changes;
Genetics, the small remaining sheep became inbred.

As far as I can see, not much has changed, except much brush has been removed by the Bullock and Aspen fires of 2002 and 2003 which cleared about 115,000 acres.

AZGF does not have a specific set plan, but will use “adaptive management” to try to make the program a success. Sacco noted that the collars on the sheep are not working as well as hoped. It cost about $100,000 to collar the 31 sheep.

Mountain lions prey upon deer, javelinas, and turkeys in the Santa Catalinas. The lions need the equivalent of one deer per week. The introduction of Bighorns has added to their dietary variety.

AZFG has come under fire because they objected to the dining etiquette of the mountain lions and had two of them killed. Such extreme action by AZFG has spawned controversy and objections from many people because AZFG is punishing the mountain lions for their natural behavior. What did AZFG expect? I agree with those who object to killing of mountain lions. AZGF says it will hunt down only those mountain lions that become Bighorn “Specialists” but even that does not sit well with the public.

From their observations in the Kofa Game Range, AZFG claims that only a few mountain lions become Bighorn “specialists,” preferring them to any other game.

Dr. Shaw, who favors the Bighorn reintroduction program, gave a more general assessment of such projects. He says that most fail for a variety of reasons including that the reintroduced animals don’t know the territory and that captive-bred animals don’t have the necessary survival skills.

As far as I can see, all the factors that may have led to the demise of the Bighorns in the 1990s are still in play. It remains to be seen whether AZGF or the mountain lions will prevail.

Arizona Game and Fish Big Horn Sheep Website.