Commentary by Robert Bauer
“…any devastation of western rangelands, is due rather to an overpopulation of cattle, which have been found to outnumber the wild horses 100 to 1…”
As a biologist, I have been involved in documenting the issues concerning this nation’s wild horses for years, along with many others. While keeping in mind the emotional effect that the wild horses have on millions, both in a negative and positive way, I have also devoted myself to understanding and communicating, from an objective and scientific standpoint, the truth about wild equine. Nature has proven herself to be able to maintain a thriving natural ecological balance, untouched and unmanaged, if allowed, without artificial intervention by mankind. This, also incorporates this nation’s wild horses. Wild horses and burros are not overpopulated as many have attested, nor are they a detriment, but rather an overwhelming benefit. On our western rangelands, indeed, any devastation of western rangelands, is due rather to an overpopulation of cattle, which have been found to outnumber the wild horses 100 to 1.
Photographic evidence has shown that the grazing habits of cattle, coupled with their physiological makeup, has caused an uprooting of vegetation, as well as the destruction of riparian habitats and other water sites. This in turn has had a destructive effect on wildlife, including the wild horses who use these same natural resources. The positive effects of wild horses on our western rangelands can be understood by reflecting on these following truths.
1. It must be realized that nature through its own mechanisms is fully able to maintain natural ecological balance, without human intervention. It does this through physiological differences, found within each species inside any given ecosystem. Each of those differences, contribute as a vital factor in a broad ecological equation, allowing each species, including wild equine to fill a vital niche in the balance of nature. It also accomplishes this through the numbers or density of any given species of animal or plant within that system, in conjunction with competitive species, and the carrying capacity of the land. Sterilization and or contraceptives have been proposed to check wild equine population growth disregarding the presence of its predators, natural environmental factors, and competitive grazers. Natural predation and environmental impacts are vital in regulating the numbers of ungulates and ruminants alike in any given area. Density dependent inhibition, however, must not be ruled out and plays an important role as well. In this scenario, the numbers or density of wild equine, versus competing ruminants, as the pronghorn antelope, will each fluctuate in response to the other based upon the carrying capacity of the land, yet always in perfect balance. The Pronghorn and other ruminants, therefore, need the presence of wild horses and burros and vice versa. Each population will have the effect of keeping the numbers of another competing population at levels that are ideal for the carrying capacity of the land. As an added note, it is deep in my heart to convey the truth that nature through its own mechanisms is fully able to maintain natural ecological balance, without human intervention to adjust it, even though it is necessary to monitor nature, communicate those facts, for the purposes of adjusting mankind to accommodate nature so that it can be itself.
2. Within the physiological and behavioral makeup of the wild horses and burros, there also exist what could be called self-regulating mechanisms. These mechanisms serve to govern reproduction and subsequent population growth or the lack thereof. An increase in the gestation period of wild horses, (delayed implantation), and spontaneous abortion come into play during periods of environmental stress within a system, as well as selective breeding by a stallion within a band, if indeed the stallion breeds at all. In short, environmental stress has the overall effect of limiting reproduction. Added to this are annual mortality rates established in a NAS study which range between 14% to 50% in wild horses up to 1 year, and 5% to 25% for horses older than this. These above mechanisms do, indeed maintain the proper density of wild horses in any given area, perfectly, in balance with competitive grazers and predators. It does this without sterilization, without the PZP contraceptive, and without roundups. It therefore establishes at any given time, nature’s own appropriate management levels, levels which nature adjusts continually, based on the above biological factors.
3. Also, what must be understood is that nature is dynamic, and not static. This infers that it continuously fluctuates and adjusts itself, through its own feedback loops, from the molecular, all the way up the scale of organisms. Because it is dynamic and not static means that its functions cannot be confined to finite thinking, and fixed statistics but must be allowed, through its own mechanisms to maintain itself, hands off, so to speak. In other words, nature cannot be limited at any given time to a given number, or average of numbers, that mankind deems appropriate. An example of this is the Bureau of Land Management’s, “Appropriate Management Level”, of wild horses in their legally designated lands. Mankind’s sole responsibility must be focused on keeping the restrictions off nature, so that nature can be itself, and not an offspring of man’s seemingly brilliance. The moment mankind seeks to alter nature according to a fixed number, or an average of numbers, is the moment that nature and balance itself begins to break down. At first it occurs little by little, yet as artificial alteration persists, the breakdowns become greater and greater. This has occurred in every branch of nature, where mankind has endeavored to manage natural balance, assuming nature to be static and not dynamic.
4. Another issue that must be considered is that the numbers of the wild horses remaining in the wild are not even in the teens of thousands anymore, contrary to the assertions to the contrary. This statement may seem bold yet is based upon Bureau of Land Management statistics, factoring in reproduction, PZP, adjustment of sex ratios, and the thousands of wild horses and burros that have been continually removed. Factored in also, are mortality rates, already mentioned above, both first year and adult, that nature herself applies. These issues combined, have driven numbers in most areas out west down to levels where genetic viability has been compromised and far below total numbers that the BLM have stated as still existing in the wild. Also, with continued use of the PZP contraceptive, population growth will be driven down even further. Reproduction will continue to decrease dramatically because of PZP, but mortality percentages will remain the same. With the use of the contraceptives, or sterilization methods, therefore, mortality will completely overwhelm reproduction, accelerating population decline in our wild equine.
5. It is said by some that because of the vast removals, nature compensates with a population explosion of wild horses, serving to reinforce the elevated population claims. Incorporated into this thought, are low levels of predators, in many areas. It must be remembered, however, that the varied mechanisms of ecological balance do not work independently of each other, but always in concert. Where one mechanism may lack, as the predators, other facets of balance will engage more vigorously yet always governed by the carrying capacity of the land. Predator, Prey studies and statistics have consistently affirmed that predator numbers and prey numbers follow each other. Simply speaking, when prey numbers are high, nature compensated by increased numbers of predator species. The opposite is true also. When predator species decrease, density dependent inhibition engages more vigorously, causing the prey species, in this case wild horses, to reach a limit based upon the carrying capacity of the land, and then decrease in number. Equine mortality on the range, as mentioned above is shown to be very high in the first year of life, not to mention adult mortality, again not all by predators. This and common sense reproductive facts of wild horses, oppose every allegation of population explosions in wild horses.
6. The free roaming habits and social behavior of the wild horses and burros, allow them to harmoniously coexist with every competing ruminant. Their physiological makeup coupled with continual movements have a revitalizing effect on soil and vegetation. This in turn positively impacts other grazers, and subsequently predators as well, who prey upon them. The presence of wild equine in a multitude of ecosystems has proven to result in a beneficial cascade effect, rejuvenating entire areas where they have been reintroduced, both in terms of flora and fauna. This has been documented in many geographical locations throughout the world. Noting these indisputable facts, the wild horses and burros can without question be considered a keystone species. Removing our native equine from their legally designated areas and or tampering with their numbers has and will continue to have a reverse and detrimental effect on our western rangelands.
Conclusion. The answer to ecological balance, therefore, in our western ranges doesn’t lie in experimentation, sterilizations, contraceptives, adjustment of ratios, the institution of removals, or mass euthanasia. The answer lies in the termination of all roundups and a release of the wild horses and burros, in holding facilities, back into the areas from where they were taken. All that is necessary for a “Thriving Natural Ecological Balance”, is to keep the restrictions off nature, and allow her to regulate herself untouched.
The wild horses and burros will continue as the powerful symbol of this nation’s freedom, yet vital components of ecological balance if, and only if, we allow nature alone, through its own dynamic methods to dictate the numbers in the wild that are to exist, at any given time.
Robert C. Bauer