NATIONAL PARK SERVICE Sonoran Desert National Park, Arizona: A Proposal

Threats to Park Resources

The integrity of a significant portion of the study area is greatly endangered. This is a result of grazing and mining activities which are presently authorized in the existing Organ Pipe Cactus National Monument.

Although the grazing resource in the Monument is adjudged by ecologists to be of marginal value, cattle raising has been carried on, presumably at a profit, since around 1919. When the Monument was created in 1937, Mr. Robert Gray and his three sons were issued a permit which provided that the Gray partnership, during the lifetime of the four individuals, could continue grazing 1,050 head of cattle on accessible lands within the boundaries. The three sons survive. One of them owns 157.67 acres of patented land and leases two sections of State land, all within the Monument.

There is clear and long-standing evidence that grazing is a critical factor in many of the dramatic vegetational changes that are taking place in the Sonoran Desert. Research at both Saguaro and Tonto National Monuments has shown that grazing in these areas has had a marked decimating effect upon stands of saguaro cactus, by limiting reproduction of the species. It is reasonable to assume that the same inhibitory effect operates at Organ Pipe Cactus National Monument upon the saguaro and two other notable species of columnar cacti: organpipe and senita. Botanical authorities state that these cacti are just one class of many native plants so affected.

Opinions and inferences by recognized authorities regarding the effects of grazing upon unique vegetational types at sites well within their range of distribution suggest that such effects occurring at the outer limits of the ranges are even more severe. This is apparently the case in the National Monument. Grazing induced changes may well be taking place in the biota which will threaten their existence and defeat the purpose for which the Monument was established.

As can be expected, grazing is heaviest in the vicinity of the watering places. Naturally these wells were located in the heavily vegetated areas and, as a result, grazing damage in these areas is serious. This is highly regrettable because these areas are of great importance to the native wildlife and are also of the most interest to visitors.

Researchers in range management have established that an average size cow will consume about 20 pounds of dry forage per day if available, or a total of 7,300 pounds per year.* In desert country such as this, forage is, of course, not readily available, but it would be safe to assume that a cow in the desert would consume at least one-fourth of this amount. At this conservative rate, the 1,050 head of cattle covered by the existing permit would consume nearly 1,000 tons of native vegetation per year. The situation would not be nearly so serious if this consumption were spread evenly over the entire area and if it included equal portions of all plant species. This is, of course, not the case at all, and it is inconceivable that the removal of this much highly selective vegetation each year in this area of relatively sparse plant cover would not adversely affect the important biological balance which the Monument was established to preserve.

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*Range Management Handbook, U.S. Forest Service.

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This condition is aggravated by the fact that, like other ranchers in the desert country, the permittees have, during times of drought, cut trees and burned cholla free of spines to provide stock feed.

Adverse effects are not confined to the biological values. The safety of visitors is endangered by cattle grazing under "open range" practices that extend to the unfenced road right-of-way of State Route 85 within the Monument. During the past two years, car-cow accidents have averaged 25 per year; in 1963 many people were injured and one person was killed.

Nuisance factors incident to grazing include intrusion of thirsty cattle into developed areas such as the visitor center grounds, campgrounds, and residential areas where they inconvenience visitors and damage facilities to such an extent that fencing at Government expense is necessary. Dead cattle are seen at times along the road and have polluted water holes. In addition, grazing is a source of embarrassment to the Service because visitors question the propriety of allowing cattle in a Monument which was established primarily to preserve natural biological values.

At the present time there is no grazing in the Cabeza Prieta Game Range except for one legal allotment in the eastern end in the vicinity of Ajo. Part of this lies in the small segment of the Range that was excluded from the study area. Prior to February 1965 there was widespread trespass grazing on the eastern portion of the Range by the Gray partnership, but this has now been terminated by order of a Federal judge as a result of suit brought by the Bureau of Sport Fisheries and Wildlife.

Prospecting and mining are also permitted in Organ Pipe Cactus National Monument. This marked departure from the normal policy concerning mining in the National Park System is the result of an act of Congress — of October 27, 1941 (55 Stat. 745) — which specifically authorized prospecting and mining in the Monument. In part, this was brought about by the nationwide search for minerals in connection with the national defense emergency at the time.

To most people, "prospecting in the desert" brings to mind a lonely, bearded old man with a pick and shovel and his trusty burro. If this were the case, prospecting on the Monument would not be much of a problem. However, today's methods involve bulldozers, drag lines, power shovels, earth movers, drilling rigs, dynamite, and innumerable trucks. In addition to damage on the claim itself, rather substantial roads are dozed out. When the claim is abandoned for lack of a find, as is usually the case, the scars remain, along with the trash, the tailings, and the debris generated by the effort. In this fragile desert country, the scars do not heal and serious erosion invariably results.

Geological investigations in the Monument reveal that only about one-tenth of the area is mineralized, and there the deposits are sparse and occur chiefly in small, irregular veins. Principal commercial ores are low-grade copper and modest amounts of gold and silver. No mineralization occurs in the area resembling in any respect the large copper deposit at the New Cornelia Mine near Ajo, 33 miles north of the Monument headquarters. This find is singular. In general the occurrence of commercially significant metallic or nonmetallic deposits in this part of Arizona is low in comparison to that in the more mountainous sections of the State. A known possibility within the Monument is at Copper Hill. Since 1941 three major companies have explored there by geophysical techniques and core drilling to a depth of 2,000 feet, but apparently the findings are not promising, as the companies have not exercised their options.

Although prospecting has been permitted in the Monument for more than 23 years, there has not been a single mining venture that has proven profitable. The actual record of negative showings is much longer, for despite intensive prospecting over the past 200 years, no significant mineral discovery has ever been made in the Monument area. Yet the embers of hope are never quite extinguished, and the practice of prospecting, with all its destructive effects, continues on as long as it is legally authorized. The total number of claims is unknown, but none is being actively operated at present. From the foregoing, it can be honestly concluded that the complete elimination of prospecting and mining from the National Monument would probably cause no economic hardship to individuals, companies, or the region.

As perhaps no other form of land use is more destructive to the natural values of the National Monument, every effort should be made to extinguish existing claims and terminate prospecting at the earliest possible time.

Military Use of the Game Range

An important factor affecting the feasibility of an expanded park area concerns the military use of the Cabeza Prieta Game Range. Almost all of it is overlapped by the Williams Bombing and Gunnery Range, and at the present time the air space over most of this portion of the study area is used by the Air Force and Marine Corps for air-to-air gunnery practice and missile firings. Although there are no facilities or targets on the ground and no air-to-ground firings, there is danger of falling hardware and spent projectiles. As a result, the area is closed to public use of any kind except on most weekends and, with special permission, during the brief periods when it is not being used for military purposes.

Although no formal inquiries have been made to the military authorities, available information from local sources strongly indicates that the Defense establishment would be extremely reluctant to relinquish any part of this air space, which currently involves an area three times as large as the Game Range. In fact, it is reported that additional space is being sought.

The apparent hopelessness of the outlook, however, should be countered by recognizing that weaponry techniques and concepts are changing rapidly, and the possibility cannot be dismissed that the existing pattern of military use over the Cabeza Prieta Game Range could become obsolete. Moreover, there is precedent for the abandonment of Defense use of an area brought into the National Park System — as at Padre Island, Texas, parts of which were formerly used as naval air target ranges. Eventually the gunnery purposes to which the Game Range and adjacent lands are subjected might just as well be accomplished over some sector of the Pacific Ocean. At any rate, these are matters which should be weighed in evaluating the feasibility of the National Park proposal.

On the bright side, the Game Range under its present joint use for wildlife and military purposes, to the exclusion of the public, is being afforded a high degree of protection. Its ecological integrity and natural condition are almost perfectly preserved. This is indeed fortunate, because such an inviolate status constitutes a kind of "deep freeze" which will keep the area intact, to be considered for National Park purposes if and when military use is terminated or modified for any reason.