The History of the Introduction Of Pronghorn Antelope to Lana`i
In 1959, the state Department of Agriculture and Conservation (later bifurcated into the Department of Agriculture and the Department of Land and Natural Resources) undertook to introduce pronghorn antelope to the island of Lana`i. The events that followed were described in a brief report by Lyman Nichols, a wildlife biologist. Portions of Nichols’ report, “The History of the Antelope Introduction on Lana`i Island, Hawai`i,” follow:
On November 30, 1959, 56 pronghorn antelope were trapped by the Montana Department of Fish and Game. These animals were to be shipped to the island of Lana`i, Hawai`i, as a part of a program designed to increase the wildlife resources in the islands by the Division of Fish and Game, Department of Agriculture and Conservation. They were to be the first introduction of pronghorns outside the continental limits of North America.
The rugged canyons and ridges of the one 3,000 foot mountain peak on Lana`i are occupied by a herd of wild (feral) goats which are managed as game animals and hunted in annual open seasons. The lower slopes of the island, usually below 500 feet in elevation, form the habitat of the Axis deer, which are highly regarded as game animals and carefully managed for hunting. Part of the intermediate slopes below the 1,200 foot central plateau are not well suited as Axis deer habitat and have been stocked with the mouflon sheep, which appear to be flourishing and increasing.
Approximately 35 square miles of the upper slopes of the island are open grassland — too open for deer and not generally suited to the mouflon. Feed in the form of grass, forbs, and low shrubs is abundant, but the area was practically devoid of game mammals, and none of the big game already on Lana`i showed any tendency to occupy this open range. There is no livestock on the island, with the exception of a few private saddle horses.
When the author arrived on Lana`i in late 1957 as resident wildlife biologist, he noted that this unoccupied, open range appeared very similar to pronghorn antelope country in eastern Colorado and Wyoming, and investigations were begun into the suitability of this area as pronghorn range, and into the possibilities of procuring antelope from one of the western states for a trial introduction. It was eventually decided to go ahead with the experiment, and the Montana Department of Fish and Game agreed to furnish the animals.
The 56 antelope which were trapped were checked for signs of disease and parasites in Montana, and then shipped by truck to Seattle and thence by freighter to Honolulu, being accompanied by James McLucas, trapping foreman for the Montana Department of Fish and Game. The animals were shipped in plywood crates measuring 4 x 4 x 8 feet in dimensions, and five or six antelope were in each crate.
When they arrived in Honolulu on December 9, 1959, there were 44 antelope remaining, the rest having died en route of injury or pneumonia due to cold and rainy weather on the way. These were then sprayed with Malathion as a preventative to the introduction of ectoparasites into the islands, and then trucked to Hickam Air Force Base, where they remained overnight. Four antelope were given to the Honolulu Zoo; the remaining 40 were flown to Lana`i for release. Two more died between Honolulu and Lana`i. The 38 animals reaching Lana`i were released from their crates into a small holding pen which was located on a large, grassy flat on the northeast side of the plateau at about 1,700 feet elevation. When they were all out of the crates and grouped in a single herd, the gate was opened and they were eased into the open and freedom.
There are no natural water holes or streams on Lana`i, so artificial water units were established for the antelope. However, one factor was overlooked in the release, and was to cause serious trouble almost immediately: the antelope had never seen salt water, and were used to large fresh water lakes in which to quench their thirst. They took one look at the large, blue “lake” several miles down slope from the release area, and headed directly for the Pacific Ocean! Unfortunately, they bypassed the water units placed in the release area. Sometime during the first night following their release, they found their way through the heavy algaroba forest lining the coast and came out on the narrow sand beach between the forest and the sea.
The next day, they were found wandering disconsolately up and down the narrow beach, searching vainly for drinking water, and unable to return to the cooler, open country above because of the solid forest which they refused to enter. A crew of volunteers was immediately rounded up and the antelope, now suffering from lack of water, were herded up the beach to an open ridge that led to the higher rangeland and water units. During the drive, some of the animals became confused and took to the water, swimming out over the reef towards the open sea; however, the surf turned them, and they returned to shore with no losses. A few became lost in the trees and did not make it up the ridge with the main herd. Most of these were subsequently chased — or captured and carried — up to the open range of the release area, but at least two died on the beach, probably from the effects of drinking salt water.
The majority regained the release area and found the water units. They remained there for a number of days before commencing to wander. By January 20th, the known number of survivors had been reduced to 18. A number had died from the effects of having their eyeballs punctured by the thorns on the algaroba trees while they were at the beach, and others had wandered from the main herd and could not be found. Most of the 18 were suffering from scours, probably brought on by the severe change in diet, and it is possible that some losses were caused by this.
No more known losses have occurred since mid-January, and the 18 survivors gradually regained their health and high spirits, and recovered from the scours. after the end of February, they began wandering over a large part of the available range, splitting into several smaller groups which constantly shift back and forth, making an accurate count difficult. Although they found and used most of hte water units put out for their benefit, their wanderings took them away from any water source for days at a time, and they apparently subsisted entirely on dew water. At the elevations where the antelope range, heavy dews occur nightly even throughout the dry season and the forage is moderately to soaking wet each morning, thus providing a minimal source of fresh water for big game. The antelope appear to subsist very well on this dew water alone, judging by their occasional long trips away from standing water.
Of the 56 antelope that were shipped from Montana, only seven were adult does; the rest were short-yearling buck and doe fawns. One of the mature does died en route, but the six that reached Lana`i have survived the release with no loss. This fact should be well worth remembering in any fugure introductions — that mature antelope seem to be able to withstand the drastic changes in climate and diet much better than young animals.
Sometime in late May or early June, five of the adult does gave birth to eight fawns — three sets of twins, and two singles. These were not discovered until late June due to the wildlife staff having been tied up with other duties. At the time of this writing (August 20, 1960), the fawns are about three-quarters the size of their mothers, and all appear healthy. In fact, all of the antelope seem healthy and fat and well acclimatized at present.
It is still too early to say whether r not the introduction has been a success. At present, all indications do point to success. There is one hurdle, however, that they will soon have to face: the game-bird hunting season which begins in November. The antelope range covers too large a portion of the available bird hunting area to be closed to hunting in the face of local pressure. The danger is not so much in the bird hunting per se, but in the fact that most of the hunters use bird dogs which can easily get out of control, chasing the antelope hither and yon. There is not much that can be done about this, unfortunately.
The interest of local sportsmen — as well as Fish and Game staff members — has been intense ever since the pronghorn introduction program was announced. Most realize that it is still in the uncertain, experimental stage, and could yet fail, and that even if successful, will provide only limited hunting due to the small area involved, which can never support enough animals to provide sufficient hunting for all sportsmen each year. However, if the introduction does succeed, local hunters will someday have a chance to take an outstanding trophy that they might otherwise never have seen, and from an area that would probably have remained barren of big game.
Postscript: In the second edition of his informative text Mammals in Hawai`i, P. Quentin Tomich relates what happened to the pronghorn antelope in later years. “The herd as counted in October 1964 had increased to 129. An allowable herd size of about 250 was reached in 1966, and some hunting was permitted for the first time…
“It was thought that adaptation of the pronghorn to Lana`i, if carefully studied, could provide keys to restoration of this species in parts of its formerly extensive range in western North America. But after more than 20 years the pronghorn has not adapted well to Lana`i, probably because of nutrient deficiencies in the available range, which result in poor production and survival of kids.
“An independent study of the population was initiated in 1971, but faltered for unexplained reasons. Meantime numbers have dwindled. As of 1983 the population was reduced to less than a dozen and moving toward extinction. Thus it is of no further active interest for management as a game animal.”
According to biologists with the state Department of Land and Natural Resources’ Division of Forestry and Wildlife, the last pronghorn on Lana`i was seen in the mid-1980s.
For further reading, see P. Quentin Tomich, Mammals in Hawai`i, second edition (Bishop Museum Press, 1986). The cited text is from pages 136 and 137.
Volume 9, Number 7 January 1999
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