Developed PZP for use in 85 species
Jay Kirkpatrick, 75, for more than 40 years a leading developer of contraceptive vaccines for wild horses, deer, elk, and other wildlife, died on December 16, 2015 in Billings, Montana “from a brief but serious illness,” family and friends said.
Kirkpatrick, originally from Bucks County, Pennsylvania, spent seven years as a National Park Service ranger in Rocky Mountain National Park, Colorado, before earning a Ph. D. in reproductive physiology from the College of Veterinary Medicine at Cornell University in 1971.
Long resumé was the least of his achievements
From mid-1971 until 1994 Kirkpatrick taught biology and wildlife physiology at Montana State University in Billings, including seven years as dean of the School of Arts and Sciences. His professional biography also included post-doctoral affiliations with the University of Pennsylvania and University of California at Davis veterinary schools, as well as the Center for Reproduction in Endangered Species at the San Diego Zoo. In addition, Kirkpatrick was long affiliated with the Deaconess Research Institute, of Chicago, and in 1998 founded the Science & Conservation Center at ZooMontana in Billings, where research on wildlife contraceptives was partially funded by the American SPCA.
Further professional appointments included stints on the National Animal Damage Control Advisory Committee for the USDA; on the Contraceptive Advisory Group for the Association of Zoos and Aquariums; on the Montana Wolf Management Council; and as a frequent consultant for the Humane Society of the U.S.
Kirkpatrick turned to contraceptives research in 1971, at request of Bureau of Land Management horse management specialists Ron Hall and Gene Nunn.
Hall and Nunn enlisted Kirkpatrick’s help soon after passage of the Wild Free-Roaming Horses & Burros Act.
Recalled Kirkpatrick, on many occasions, “Two cowboys showed up at the door of my office, and asked, ‘Can you make horses stop reproducing?’”
Assigned to managing the Pryor Mountains wild horse herds, Hall and Nunn accurately anticipated that adoption demand for wild horses would be exhausted within 10 years, leaving the BLM with a perpetual glut of horses removed from the range with nowhere to go.
Porcine zona pellucida
University of Tennessee researchers hypothesized in 1972 that an effective contraceptive vaccine for hooved animals might be based on porcine zona pellucida, extracted from the ovaries of slaughtered pigs.
Following up, Kirkpatrick began field-testing the PZP-based product that became ZonaStat-H in 1987, with sufficient success that PZP use became common in zoos long before being introduced into free-roaming wildlife.
Even works in elephants
Zoos throughout the world now use PZP to limit births of about 85 hooved species, even elephants. Late in life Kirkpatrick participated in tests of PZP to control wild elephant populations in South Africa.
Kirkpatrick also tested PZP somewhat less successfully with non-hooved captive wildlife, including beaver.
Banned in Illinois
Opportunities to demonstrate PZP use among free-roaming wild horses, deer, and elk were restricted, meanwhile, despite success in captive animals, partly by the difficulty of administering adequate doses often enough, but mostly by political opposition.
Hunters, in particular, have for decades seen contraceptive wildlife control as a threat to hunting opportunities, and the pretense that hunting is a necessary part of wildlife management. Illinois, one of the states where surplus deer populations are most often culled, even prohibiited using contraceptives in wildlife.
The National Park Service, however, in 1994 began allowing Kirkpatrick to use ZonaStat-H among the wild horses of Assateague Island, Maryland. The application was successful, helping to stabilize the Assateague Island horse population at about 100.
The first such vaccine approved and registered by the EPA, ZonaStat-H finally entered use as Hall, Nunn, and Kirkpatrick had originally intended when in 2011 it was injected into about 1,600 free-ranging mares across the U.S., including the Pryor Mountains of Montana and the McCullough Peaks region of Wyoming. The Bureau of Land Management found that the introduction of ZonaStat-H reduced the rate of growth of the Pryor Mountains wild horse herd, a particularly politically and ecologically controversial population, by more than half.
Recalled Suzanne Roy, founding director of the American Wild Horse Preservation Campaign, after a long tenure with In Defense of Animals, “I knew Dr. Kirkpatrick for a long time, since the day we hiked the tule elk range at the Point Reyes National Seashore [in northern California] together over 20 years ago. I remember clearly the day I met him and thinking that truly this man was different––here was a scientist with a heart. Thanks to Jay and another wonderful scientist/humanitarian, Dr. Susan Shideler of UC Davis, whom we lost eight years ago, we got the National Park Service to implement a birth control program that saved 40 female elk from being shot and killed each year by park sharpshooters. Those were only some of the thousands of wild animals––from wild horses to deer to bison and elephants––whom Jay prevented from capture or killing through his development of PZP vaccines for use as an alternative to lethal management.
“Huge heart for animals”
“Jay had a huge heart for animals,” Roy continued, “and was funny, smart, sometimes curmudgeonly, always lovable. He navigated the difficult political waters of wildlife management with humor and wisdom. To claims made by his critics and supporters alike, he had six words, ‘What is your evidence for that?’ Good science was always his guiding principle and he put it to use for the benefit of wild animals everywhere.”
Agreed Return to Freedom’s American Wild Horse Sanctuary founder Neda Stram, “Jay was a trusted friend and mentor, always generous with his time to help Return to Freedom create the least invasive and humane management possible for the wild horses at our sanctuary, so that they could live as natural a life as we could provide within our fences. He was an active and accessible member of our advisory board.”
Stram recalled “a trip Jay and I took to propose a solution for some 500 wild horses on a 600,000-acre private ranch. As we were driving through the vast area, one of the range managers shot a mother coyote. Jay went silent until we got back to the lodge. He was deeply disturbed, stating emphatically that the shooting was not true conservation, that the death of that coyote mama meant a den of pups would suffer as they starved to death.”
Said BC Deer Protection Society founder Colleen Bailey, “I only had a few interactions through the years with Jay, but all were filled with amazing growth for me. He was a fountain of scientific information and fun stories. Most of my interactions with him were through my work against urban deer culls here in British Columbia. He was an amazing resource and supporter of non-lethal methods to control populations of all kinds of species finding themselves in trouble with humans.”
One of Kirkpatrick’s last trainees
Testified Wild Horse Education founder Laura Leigh, “I was one of the last people who will ever be trained by Jay. Jay devoted his life to preservation of species with a focus on humane management. He was an unpretentious man who rode a moped and always wore the same sweater. Regardless of the rumors out there, Jay never patented his work. It was a gift to the animals and to those trying to protect them.
“I have witnessed more wild horses removed from the range in the last six years than any other observer, public or government,” Leigh continued. I have seen tens of thousands removed by helicopter roundup with my own eyes. Fertility control [developed by Kirkpatrick] has been used safely and successfully in wildlife populations of multiple species for decades. It is the only approved vaccine that is reversible that does not interfere with hormonal cycles (behavior). It can be administered without capture or handling. It can stabilize, or reduce, population. It is simply an isolated animal protein, not a chemical or synthetic concoction,” with “no environmental risk,” which Leigh strongly endorses after years of observation of both PZP use and of the alternatives.
“Jay told me how much he hated roundups and commented that I must have a ‘stomach of steel,’” Leigh continued. He was extremely excited about the things we were working on, broad areas with strong data collection. He was saddened that so many refuse to look at facts and correct mistakes. The ‘bash’ campaign against his work,” conducted by opponents of wild horse fertility control, “hurt him as a person. Jay’s work was for humane and sane management, yet he is often not treated with the respect he deserves.”
“Not a bunny hugger”
Explained Kirkpatrick himself to National Geographic in 2009, “I’m not a bunny hugger, but I’ll never attend another gather as long as I live. They’re flat-out inhumane. There are three reasons why these gathers are an unsatisfactory solution to the problem of numbers. Firstly, it’s genetically irresponsible to be constantly pulling off young horses whose genes will never get expressed. Secondly, every time you pull horses out, the reproductive efficiency of the horses who remain increases. And thirdly, the behavioral consequences for the horses are profound.”
Elaborated Kirkpatrick to Jeremy Cox of the Salisbury (Maryland) Daily Times, “Everything has an impact. Three white-tailed deer will have an impact on Assateague. The question you have to ask is, ‘What is an acceptable impact?’”
Among Kirkpatrick’s most controversial contentions, detailed in the 2001 Fund for Animals video El Caballo: The Wild Horses of North America, directed by Doug Hawes-Davis, was that wild horses should be regarded not as an introduced species, as historical and genetic evidence indicates and as the Wild Free-Roaming Horses & Burros Act incorporated into law, but rather as a native species which was temporarily displaced.
Kirkpatrick explained in El Caballo that whatever happened to the native North American horses 11,000 years ago, when they vanished from the fossil record until Spanish conquistadores brought them back barely 500 years ago, appears to have occurred even more abruptly than the extinction of the dinosaurs. Since there are as yet no archaeological sites showing evidence that horses were killed and eaten by humans, who were just then invading North America from Asia, the horses were apparently not hunted to extinction, Kirkpatrick added.
Arrived already well-adapted
Kirkpatrick hypothesized that horses might instead have been extirpated from North America by a fast-moving introduced disease. He noted that the glaciers which had covered most of what later became the North American wild horse range were then in retreat, and that there have not been any big ecological changes in the American west since then, other than the recent changes associated with human settlement.
Kirkpatrick went on to outline in detail the rapid reclamation of the ancestral horse range by the first escaped Spanish horses and their descendants, who obviously were already supremely well-adapted to the conditions they found.
Finally, Kirkpatrick mentioned the hypothetical possibility that the Spanish horses might have met and mingled with a few hardy bands of survivors from the extinction event of 11,000 years earlier. The absence of recent fossils of horses, Kirkpatrick explained, does not necessarily mean horses had not survived in North America; it merely means that they had not survived in great numbers on soils conducive to forming fossils. Many other species known to have persisted here throughout the same epoch also left little fossil trace.
Kirkpatrick, unlike some other wild horse advocates, did not try to take his hypothesis into court as a pretext for stopping roundups. Characteristically, Kirkpatrick awaited the discovery of physical evidence before trying to further advance what he saw as a theoretical likelihood.