by Clio Smeeton*
Swift fox conservation has been beset by
uncertainties of
their taxonomy against a history of habitat loss. Their future in
Canada
relies on reintroduction.
The tiny arid land foxes unique to the North American Great Plains have gone through such a multiplicity of name changes since their first discovery by Europeans in 1823 that the Oglala Sioux name of Mee Yah Chah, meaning "the lousy one", must be the only constant one.
Mee Yah Chah, the swift fox, is a delicately beautiful animal, its grey-buff and ochre coat blending into the prairie landscape with only the black tip to its tail and black patches on either side of its muzzle standing out.
The smallest of North American canids, the swift fox weighs only 2.3 kg as an adult and must rely on something other than weight, fangs and muscle to survive. Its den preserves it; speed protects it and ensures its hunting success. Swift foxes can cover shortgrass prairie at more than 25 mph.
From the time of its first description by Say as Canis velox, and transferral by Audobon & Brachman to the genus Vulpes in 1823, the swift foxµs taxonomic status has always been in dispute. As the Europeans expanded westward across North America the arid land and Great Plains foxes were given an increasing number of taxonomic descriptions: Vulpes macrotis (Merriam 1888), Vulpes velox hebes, V. macrotis neomexicana, V. muticus (Merriam 1902), V. Arsipus (Elliot 1903), V. macrotis devius (Nelson & Goldman 1931), and V. macrotis zinseri (Benson 1938).
Finally, in an attempt to organise the proliferating nominal Taxa descriptions they were all grouped under two headings and recognised as subspecies of, or synonyms for, Vulpes velox or Vulpes macrotis, the swift and kit fox (Seton 1929, Benson 1938, Grinnel 1933). The arguments for and against subspecies recognition have never been settled, in most part because the foxes described have been extirpated over most of their range. By the time the swift fox (Vulpes velox, or Vulpes velox hebes) was recognised as a species, it had vanished from its Canadian locale.
This uncertainty has affected many attempts to conserve the threatened populations of this tiniest Great Plains canid, and has made it difficult to establish population numbers. It has also produced a paradox in that the North American swift and kit foxes are harvested in the US where remnant populations still occur, whilst being protected in Canada, where they are extinct.
In the USA there have been no national, or State by State swift fox surveys. Within the swift fox range, three States list it as an endangered species and provide protection: North Dakota, where it is extirpated, South Dakota where there is an estimated population of 50-100 animals, and Nebraska where the unknown population is believed to declining over most of the State. In Montana, where no swift fox other than radio-collared animals from the Canadian reintroduction programme have been sighted, it can be hunted, poisoned, and trapped outside the closed season. In Wyoming the swift fox can be trapped, shot and poisoned at any time of the year.
In the remaining seven States it is classed as a "furbearer", governed by hunting and trapping regulations applicable to other commercially harvested species. In Minnesota and Iowa no sightings have been reported for many years. In Oklahoma, Texas and New Mexico the population status is unknown, and both Vulpes velox and Vulpes macrotis are lumped together as one. In Colorado, where its status is classed as "not common", the swift fox is hunted and trapped. In Kansas the status is guessed to be "common", and furbearer hunting/trapping regulations apply.
In Canada the species is classed as "Extirpated". The last swift fox was sighted in Saskatchewan in 1930.
Merriam's 1902 subspecies classification of Vulpes velox and Vulpes velox hebes could well be substantiated by current genetic research, if funding to collect the blood samples from the South Dakota population is obtained before that population declines completely.
The recent and ongoing genetic DNA research of Dr. Robert Wayne has shown that the swift fox (Vulpes velox) of the Northern high Plains and the kit fox (Vulpes macrotis and Vulpes macrotis mutica) of the Southern Plains and the San Joaquim valley are distinct from each other. Although no overall population surveys have been done on the United States' swift and kit foxes, Dr. Wayne's findings in dividing swift from kit fox will have halved the guesstimated numbers of these animals in the wild.
All the time that these little foxes (under any of their names) were being added to the scientific lexicon of North American species, their habitat was being rapidly changed.
In less than 150 years a sweeping landscape, dominated by grasses, the prairie dog (Cyomys) and the North American bison (Bison bison), was transformed into a severe patterning of chequerboard grain crops. The low western wheatgrass, buffalo grass and blue grama grass had gone, their place taken by squares of tawny gold or black ploughed land filled with fertilizers, herbicides and pesticides. A land where, in the "dirty thirties", dust devils and the ever-present prairie wind had whirled the humous of thousands of years into the air to drop in measureless tons on New York and the Eastern Seaboard.
The ideas of two Illinois inventors of the mid 1800s, Johne Deere and "Uncle Joe" Gliddon, have had a profound effect on the survival of the swift fox. John Deere's prairie plough made it possible for a farmer and three-horse team to break an acre of virgin prairie in a day. The three-horse team has given way to huge tractors pulling ten-bottom ploughs which have torn off the delicate membrane of tough rooted grasses shielding the soil from the wind. The stripping metal bow of the ploughshare delved into and destroyed the foxes' earths.
Swift foxes use their earths year round. The earths are expanded from a vacated prairie dog burrow, abandoned American badger's sett, or coyote's hole. The many entrances, 18-23 cm in diameter, lead 76-90 cm below the surface into a tunnel system extending from 4.5-9 m. One earth alone is not sufficient for a swift fox's needs. These elaborate earths shelter the swift fox against people, coyotes and eagles. The insulating earth protects them from the soaring heat of summer, the bitter winter cold, and from the ever-present winds. John Deere's invention stole that shelter and left the swift fox unprotected.
"Uncle Joe" Gliddon was granted a patent for barbed wire on 8th December 1874, and the prairie biome was changed for ever. Barbed wire protected the land from the plough, preserving it for cattle. In the eye of the rancher the prairie dog, the prairie wolf and the coyote threatened his cows, and poison was his answer.
The intensive poisoning programmes for coyote and wolf decimated the swift fox. The eradication programmes to remove the prairie dog wiped out the black footed ferret and swift fox too, removing in one fell swoop protection, shelter and food source. The poisoning programmes for the "control" of prairie dog towns in the US are still in operation. In Kansas, for example, if a rancher does not want to poison prairie dogs on his own land for environmental reasons, the state has the right to come in, poison the prairie dogs, and send the rancher the bill.
In Canada it was the Saskatchewan Natural History Society which, in the 1960s, pushed for the protection of the last of Canada's prairie dogs. They started a groundswell of public opinion resulting in the 1990s' acquisition of land and establishment of the Grassland's National Park. Grassland's National Park, once completed, will be the last substantial representation of prairie grasslands left in North America; prime swift fox habitat preserved in perpetuity.
Where prairie dog towns are established they form the prey base for the swift fox, supplemented by thirteen lined ground squirrels, pocket mice, kangaroo rats and other small rodents. In late summer and autumn the foxes' diet widens to include grasshoppers, newly fledged flying ants, army worms, crickets, frogs, lizards, horned toads, small passerine birds, berries and grass. The swift fox breeds from December to February, depending on latitude; later in the North, earlier in the South. At this time the foxes are very vocal, calling through the long cold nights. The gestation period is c. 50 days. After whelping, the vixen will stay within the den with the cubs, while the dog fox hunts and feeds her. Three weeks after they have been born the cubs begin to explore the entrances of their earth and by the fifth week will be spending several hours above ground each day, with both parents providing food for them. Should the vixen be killed at this time the male will raise the cubs on his own. The family stays together as a unit, moving from earth to earth, pressured by parasites and prey availability, until the early autumn when the cubs disperse.
The attempt to reintroduce the swift fox to Canada began in 1971. The Cochrane Wildlife Reserve, founded in 1964, has bred swift foxes for reintroduction since this time, seven years before the species was declared extirpated in Canada in 1978. The Cochrane Wildlife Reserve now holds the largest breeding colony of the swift fox.
In 1970, when the first two pairs of swift fox arrived at the Reserve, sent from a Wildlife Rehabilitation Centre on the Wyoming/Colorado border, the swift fox was of no interest to either of the countries encompassed by its range.
The first pairs bred at the reserve in 1971, and soon were joined by 8 animals from the Pawnee National Grasslands, 5 foxes from the Pine Ridge Indian Reservation in south Dakota, and 2 more whose capture point is unknown. Founder foxes have continued to be added to the breeding colony almost yearly. In 1978, when the swift fox was designated by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) as extirpated, their ownership was changed by the stroke of a bureaucrat's pen from the Smeeton family to the Canadian Wildlife Service. This change of ownership was a paper transaction only, although from 1978-1990 the Canadian Wildlife Service was able to contribute $9,000 per year towards the costs of the breeding programme.
As the colony slowly grew, the Calgary Zoo, Moose Jaw Wild Animal Park and the Edmonton Valley Zoo became participants in the programme, the Calgary Zoo undertaking all veterinary work for the Cochrane Wildlife Reserve as well as studbook management for the programme. Although the swift foxes are owned by the Crown, no government funds are earmarked for captive breeding so the Canadian Government, both Provincial and Federal, relies upon the breeding institutions to find all the funding for the swift fox captive breeding programme, veterinary care, tattooing, studbook management, pathology for both captive animals and release deaths, and transport to and from release sites. Federal and Provincial funds have been expended on research into suitable release habitat for the foxes and on monitoring after release.
Swift foxes have bred in the wild in the release sites since first released in 1983. The estimated survival rate in the release sites for reintroduced captive raised cubs of the year is 33%. Estimated survival rate for first year cubs in South Dakota is 20% and in Bakersfield it is 15-17%. Known yearly recruitment in the release sites seems to outweigh known mortality, although only a very small percentage of the released foxes have been radio-collared. Numbers of animals released initially were small, but by 1990 the breeding facilities were able to produce between 67 and 110 animals for release per year. In the last 10 years, a total of 500 animals has been released over 4 large release areas in two provinces, Alberta and Saskatchewan.
The Cochrane Wildlife Reserve brought the first swift fox back to Canada and it is their aim to be permitted to comply with the IUCN's Mace Lande Criteria for a minimum self-sustaining population in at least two of the release sites and thus to have reintroduced successfully an extirpated species into its original Canadian range.
Since the European invasion the Great Plains have been ravished; between ploughing, irrigation, over-grazing, within a very short time the prairie ecosystem has become one of the most extensively altered in the world. In Canada, the rescue of a small part of the grasslands which once spread their richness before the wagons of the settlers has started with the establishment of Grassland's National Park, the protection of the prairie dog and the reintroduction of the swift fox.
* Clio Smeeton inherited a determination to conserve swift foxes from her parents who had created the Cochrane Wildlife Reserve in 1964. She now collaborates with the Canadian Wildlife Service in the Grassland National Park project to recreate the plains ecosystem. Most recently the Fauna & Flora Preservation Society has purchased kennels for her fox translocation.
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