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a transect along a rainfall gradient through the Negev desert. As in more mesic environments, these patterns appear to be driven in turn by the underlying patterns of plant productivity and species richness.

On the whole, it was agreed that a number of aspects of desert ecology would benefit from a more formal experimental approach. One area that was singled out was the role of herbivorous animals in the popula- tion biology of desert plants. Exclu- sion experiments with vertebrate, in- sect and molluscan herbivores in factorial combinations would prove most illuminating, not least because seed limitation rather than microsite limitation is more likely to be of over- riding significance in deserts.

Finally, we were reminded that deserts are unique in that they are one of the very few types of habitat that are actually increasing due to Man’s activities. The problem of desertification was discussed exten- sively in the session on landscape ecology. Joy Belsky (Cornell Uni- versity) illustrated that small changes in water availability have disproportionately large impacts on the vegetation of semi-arid African savanna ecosystems, when com-

pared to similar changes in more mesic habitats. Edith Allen (Utah State University) suggested that the absence of mycorrhizal associations in the colonizing annual plant spe- cies of deserts tends to reduce rates of recovery following disturbance. Once mycotrophic plants begin to colonize, or sites are artificially in- oculated, then recovery of ground cover is more rapid. Mycorrhizae may have a large role to play in future attempts at desert restoration.

The irreversibility of many changes in arid ecosystems was stressed by Mark Westoby (Mac- quarie University). The conventional range-management paradigm that grazing is a process essentially simi- lar to succession, but acting in an opposite direction, simply does not apply in arid environments. When grazing presssure is relaxed, the sys- tems often remain stuck where they are.

In his summing-up, Larry Slobod- kin (Stony Brook) suggested that although the same basic physio- logical machinery is used by organ- isms that live in deserts, it is usually modified to cope with either the rich but episodic resources, or the more continuously available low-quality

resources, that characterize desert ecosystems. In this context it would be interesting to know more about speciation in and around deserts; in particular, to discover whether they act as sources of, or sieves for, evo- lutionary novelties.

Although it is clear that we have a great deal to learn about desert eco- logy, what little we do know does not lead us to an optimistic prognosis. Because things tend to happen very slowly in deserts, they bear the scars of past activities for many hundreds of years. It was no coincidence that the Dead Sea Scrolls survived as long as they did. Whereas an old desert may contain a rich abundance of species that have evolved to sur- vive its conditions, a new desert tends to contain little more than the starving humans who helped pro- duce it.

References 1 Tilman, D. (1982) Resource Competition and Community Structure, Princeton University Press 2 Emlen, S.T. and Oring, L.W. (1977) Science 197,215-223 3 Cody, M. (1986) Trends Ecol. ho/. 1, 76-78

Recall to the Wild: Wolf Reintroduction in Europe and North America David S. Wilcove

Generations of ‘Little Red Riding Hood’ stories - accompanied by guns, traps and poisons - have taken their toll on the wolves of Europe and North America, In the face of considerable resistance, steps are now being taken to restore wolves to at least a fraction of their original range.

In a remote section of the Alligator River National Wildlife Refuge in North Carolina, eight red wolves (Canis rufus) are being held in large pens. Sometime this spring the doors of the pens will be opened, and for the first time in a decade the red wolf will exist as a wild species.

Red wolves were once distributed over most of the southeastern United States. Predator control pro- grams, coupled with the steady

David Wilcove is at The Wilderness Society, 1400 Eye Street NW, Washington DC 20005, USA.

146

erosion of the region’s wildlands, gradually narrowed the species’ range, until by the 1970s it was con- fined to the coastal wetlands of west- ern Louisiana and east Texas’. The Endangered Species Act was suf- ficient to protect the remaining wolves from human persecution, but insufficient to protect them from the amorous intentions of coyotes (Canis larrans), which hybridized with the red wolves. A Dunkirk-like rescue in the mid 1970s brought the last genetically pure red wolves into captivity.

Among large predators, it would be difficult to find a more benign animal than the red wolf. Solitary and shy, it feeds primarily on small mammals. Yet the US Fish and Wild- life Service has had to make a num- ber of important concessions to gain public approval for the reintroduc- tion program. When released, the Alligator River wolves will be classified as a ‘nonessential experi-

mental population’, which means that when not on refuge property they will lack the full protection of the Endangered Species Act. The agency also has promised promptly to recapture any animals which stray off the refuge. A special regulation states that there will be no penalty for the incidental take of red wolves in the course of otherwise lawful hunting, trapping, or other activities on the refuge’. Since the Alligator River National Wildlife Refuge en- courages both hunting and trapping, this last provision strikes some people as a dangerous precedent for future reintroduction programs for other endangered species.

However, the problems associated with the reintroduction of the red wolf are minor compared to those associated with the gray wolf (Canis lupus). The gray wolf is, after all, the villain of the bedtime stories. It is also a pack-hunting predator that has been known to take livestock. At one time, gray wolves occupied most of the Northern Hemisphere, including Great Britain, Europe, northern Asia, and North America from Alaska south to Mexico. Centuries of persecution have resulted in one of

0 1987. Elsevier Publmt,ons Cmbrtdye 0169-5347 X7'$02 00

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the greatest modern range contrac- tions of any extant species of mam- mal. It was exterminated in Europe, with the exception of small popula- tions in northern Spain and Italy, Germany and Eastern Europe. Wolves persist in India and the Near and Middle East, while the Soviet Union is believed to have a large population. The number of wolves in China is unknown*. In North Amer- ica, gray wolves are now largely restricted to Alaska, Canada, and parts of Minnesota.

In Great Britain, Derek Yalden, a zoologist at Manchester University, has proposed3 that gray wolves be reintroduced to the Island of Rhum, a national nature reserve in the Heb- rides. The last gray wolf in Great Britain was killed in 1743 in Scotland4. Rhum would appear to be an ideal place for wolf reintroduc- tion: it is separated from the coast of Scotland by about 14 miles of sea, its only human inhabitants are Nature Conservancy Council staff, and it has an overabundance of red deer. To prevent overgrazing and starvation, the Nature Conservancy Council culls one-sixth of the red deer (about 250 individuals) every year, By Yal- den’s calculations, that cull would support a pack of about 19 wolves3. Whether his plan will come to fru- ition remains to be seen.

In the United States, scientists and conservationists are awaiting release of the US Fish and Wildlife Service’s revised recovery plan for the gray wolf in the Northern Rockies. That plan is expected to contain a de- cision regarding a proposal to rein- troduce gray wolves to Yellowstone National Park. Between 1914 and 1926, rangers and federal predator control agents killed at least 136 wolves inside the park5. By the 193Os, the wolf was gone not only from the park, but also from the adjoining national forests and pri- vate lands.

For many biologists and conserva- tionists, the case for reintroduction is compelling: the gray wolf is the only living mammal known to be missing from the region; it was once the master predator of Yellowstone’s un- gulates; and the park and surround- ing wilderness areas have a suf- ficient prey base to support a viable population of wolves. However, there has been fierce resistance from livestock interests, concerned about the potential loss of stock and added restrictions on their ability to control coyotes.

Wolves and livestock, however, need not be mutually exclusive. In Minnesota, for example, a popula- tion of about 1200 wolves shares its

30 000 square-mile range with nearly 250 000 cattle and 90 000 sheep. Dur- ing 1979-1981, verified losses to wolves averaged 5 cows, 15 calves, and 56 sheep per year, or about one cow or calf lost for every 12 500 grazed and 6 sheep lost for every 10 000 grazed6. A program to control depredating wolves and to compen- sate farmers for losses due to wolves has been in effect in Minnesota for a number of years. In contrast, the density of domestic livestock in the Yellowstone region is lower, and most of the grazing occurs at the periphery of what would become wolf habitat.

A different sort of objection has come from some state agencies and hunters, who worry that the reintro- duction of the wolf would result in lower numbers of important game animals such as elk and deer.

For these reasons, if the gray wolf is returned to Yellowstone, it may be as an ‘experimental population’. Managers will then have to wrestle with the issues of controlling wolves that stray outside the park and com- pensating ranchers for livestock los- ses attributed to them.

Elsewhere in the United States, natural recolonization is occurring. In the fall of 1985, a pack of gray wolves from British Columbia crossed the international boundary and spent the winter in the northwest corner of Glacier National Park in Montana. In the spring of 1986, a female from that pack produced a litter of pups, the first documented case of wild gray wolves breeding in the western United States in half a century2. A few small packs, dispersing from Minnesota, have established a pre- carious foothold in the more remote regions of northern Wisconsin and Michigan.

Thus, little by little, it appears that the wolves are beginning to regain some of the ground they have lost over the centuries. Yet deeply in- grained attitudes are difficult to over- come. The government of British Columbia has recently resumed its wolf control program despite the objections of scientists, who point out that the province has already seen its wolf population drop from 23 000 in 1975 to only 7000 five years later7. When wolves began to recol- onize a portion of their range in Sweden, the response of some of the local people was to form a Society for the Destruction of the Wolf*.

Ironically, our dislike for wolves does not seem to extend to their congener, the dog. The Humane Society of the United States reports 11 human fatalities caused by domestic dogs during 1986 (R. Lock- wood, pers. commun.). In contrast, there has never been a documented case of a wild, non-rabid wolf injur- ing - much less killing - a human in North America.

References 1 US Fish and Wildlife Service (1986) Federal Register 51 (223). 4179041797 2 Robbins, J. (1986) Natural&tory May, 6-15 3 Price, C. (1986) Christian Science Monitor December 30 4 HRH The Prince Philio and Fisher. J. (‘l~~O)a)dlife Crisis, dowles Book’

5 Reese, R. (1984) Greater Yellowstone: the National Park and Adjacent Wildlands, Montana Magazine 6 Tilt, W., Norris, R. and Eno, A. Wolf Recovery in the Northern Rocky Mountains Briefing Book, National Audubon Society (in preparation) 7 Burns, J. (1987) New York Times, March 3 8 Mills, S. (1987) Oryx21,92-96