Born Free, Living Free: Wild Horse Scientists by Kay Fry

Jay knows he’s close enough now. Silently, in one fluid motion, he lifts the loaded rifle to his shoulder, takes aim, and squeezes the trigger.

A muffled pop then, a whoosh of compressed air. There’s no deafenng explosion, because this gun doesn’t fire bullets. It’s a lightweight .22, modified for a small dart containing PZP at close range.

The mare’s head flies up, more from the sound than from the sting of the needle. The dart pops back out almost immediately, as it is made to do. The wild horse trots off to the comfort of her band, no more concerned than if she’d been stung by a large, pesky horsefly.

PZP is what makes it possible for wild horses to continue living free on Assateague Island today.

In this latest addition to their notable nonfiction series, Scientists in the Field, Kay Frydenborg’s Wild Horse Scientists (Scientists in the Field Series) (Houghton Mifflin Harcourt, 2012), the author follows two scientists engaging in ground-breaking field research – Dr. Jay Kirkpatrick, whose original specialty was embryonic transplantation, and Allison Turner, of the National Park Service, assigned to monitor the wild herd on Assateague. For  more than twenty years, these two had engaged in detailed observations and laboratory studies to devise a radically new birth control vaccine for wild horses, to be used both on the barrier islands of the Atlantic coast and in the American West.

With the demise of natural predators, the single greatest threat to North America’s wild herds has been overpopulation. The only intervention then available to those who wanted to perpetuate the wild herds had been annual drives to round up the horses, pen them up, and cull the bands by roping the foals and finding adoptive owners. But the stress and danger to the horses and an increasing backlog of unadopted horses convinced horse lovers that they needed a more benign form of population control, one that was 100 per cent effective and non-invasive, one that even enabled the affected mares to live longer, healthier lives in the wild.

Enter our intrepid animal behavior scientists, whose meticulous documentation of the individual horses, collection of specimens which analyzed hormone fluctuations in the native horse population, and careful experimentation under difficult conditions–intense heat, storms, damp, misty cold, swarms of mosquitoes, and dense vegetation – allowed for eventual proof of the efficacy of cutting-edge vaccines.

Frydenborg’s text is clear and highly readable, even suspenseful at times, and the color photographs of America’s iconic wild horses stud the pages with illuminating illustrations that amplify the text. Numerous text boxes provide middle readers with background information – on the evolutionary history and color variations of horses, archaeological findings, and intriguing Fast Facts – and extensive appendices with glossary, bibliography of books, web sites and other media, and a detailed index make Wild Horse Scientists (Scientists in the Field Series) not only fascinating reading for horse enthusiasts but a great source of inspiration for young would-be scientists who may be attracted to active outdoor field study.