Listening In On Wildlife

We have been curious about other animals for a very long time—probably for about as long as we have been—but we have had remarkably little success in satisfying this curiosity. We can better predict the movements of the planets than we can those of most of our terrestrial coinhabitants.

The difficulty of collecting data is apparent to anyone who has tried, even casually, to become better acquainted with feral animals.

Telemetry involves equipping an animal with a small radio transmitter that sends either intermittent or constant signals. These signals are picked up and followed by means of mobile receivers with directional antennas. An animal can be located at distances of up to five miles, depending on the power of the transmitter, above or underground, in heavy brush, water, treetops or the air. Thus, its movements can be monitored.

Basic radio-tracking techniques were devised during World War II for military purposes. The miniaturization of equipment made it feasible for use in wildlife research. In this country the first field studies, which involved wolves, porcupines and rabbits, were made in the early 1960s. Since then everything from bats to bears and mice to moose has undergone telemetric investigation. At first the subjects were generally medium-to-large mammals, which could be fitted with neck collars to which transmitters were attached. Further state-of-the-art advances have greatly expanded telemetric possibilities. Now the technique is regularly used to track birds with transmitters in breast harnesses, or on their legs or pinions. Implantation—putting radios inside animals, as was done with the Missouri otters—has expanded during the past five years. It was made possible by developments in veterinary surgery and radio miniaturization and is employed with creatures that cannot be fitted easily with external transmitters. Now, in addition to otters, there are minks, skunks and ground squirrels carrying radios next to their innards.

Because of telemetry, there has been a substantial increase in our knowledge about many species, particularly as to territorial movement and activity patterns. As an example, by using radiotelemetry on just a few bobcats, which are secretive, nocturnal creatures rarely observed by humans, scientists in Idaho were able to plot the animals' movements and make an accurate estimate of their territorial needs, which led, for the first time, to an educated guess at the state's bobcat population. An advantage of telemetry is its cost-effectiveness. Traditional marking or banding requires a greater initial outlay of time and money; for a significant sampling, more individuals need to be captured and identified, since the percentage of specimens recovered or sighted is relatively small. With telemetry, nearly every animal equipped with a transmitter is traceable. However, now that the newness of implantation has worn off there are practitioners who admit that the technique has at times been overused for faddish reasons; some fairly trivial information has been collected by professionals largely to demonstrate their professionalism or to produce interoffice memos and dissertations of little consequence to other men or beasts. "I've seen too many telemetry studies in which the only real purpose seemed to be to use telemetry," says Dale Strickland, assistant chief of the game division of the Wyoming Game and Fish Department. Alan Sargeant, a federal biologist working out of the Northern Prairie Wildlife Research Center in Jamestown, N. Dak., is a pioneer American telemetrist, having used the technique for nearly 20 years in his studies. "Telemetry is an extraordinary tool," he says. "Because of it we can do things that were previously impossible. But people have played biological games with it, used telemetry because it was available, when it was unnecessary or inappropriate."

Astronomers peering at Mars through a telescope have, so far as we know, no effect on the planet. If they play games—use their time and equipment to little purpose—it's of no significance to anyone but themselves. The situation is different in the zoological sciences in which the nature and activity of the observer are apt to change the activity of the thing observed. Radiotelemetry can be reasonably defended on the ground that beyond satisfying curiosity, the data collected enable us to better manage and protect species and populations of wild creatures, nearly all of which are now wards of man. However, the individual animals that are subjects of telemetric studies are never benefited. Their lives are always disrupted; sometimes they are shortened. Says Sargeant, "Other things being equal, I prefer to use external rather than internal transmitters. We have had good success with implantation, but any surgery obviously increases the risks for the animal." By extension it is also obvious that no telemetry is safer for a creature than any telemetry.

An animal bearing a transmitter may be only minimally inconvenienced in the wild; the process of rigging it for telemetric study is the chief danger. Even if only an external transmitter is used, the creature must be trapped, handled and almost always either tranquilized or anesthetized, all of which, along with such things as conducting physical examinations, taking blood samples and giving immunizing injections, is called, in the jargon of this trade, "hands-on research." The benefits for research are generally thought to outweigh the risks to the animals studied, but rare creatures raise difficult questions about how much research of this sort is necessary. The debate has been intensified because of several unfortunate incidents involving highly publicized endangered species. During the past 10 years five black-footed ferrets and one California condor (respectively, the most endangered mammal and bird in the country) have died as a result of hands-on research—though not directly because of telemetry.

At present the only native ferrets known to exist—some 50 animals—are living in an isolated area of northwestern Wyoming. Before their surprising discovery a year ago, the last sighting of wild ferrets was in South Dakota in the early 1970s. For administrative and political reasons the responsibility for managing these animals has been transferred from the federal endangered-species program to the state. In consequence, Strickland has become one of the working public guardians of these animals. He feels that, among other things, they need protection from overzealous researchers. "The first priority is to preserve this population and to try to determine what environmental factors have allowed it to survive," he says. "I'm going to be very careful about giving any permits for hands-on research and this definitely includes telemetry. Simply calling a project research doesn't automatically make it desirable."

The same issue has become a confrontational one in California. A few months ago the fish and game commission there announced it was terminating permits to researchers from the U.S. Fish and Wildlife Service and the National Audubon Society to conduct telemetry studies on the surviving condors.

The essential questions about telemetry are similar to those raised by many other high-tech devices and processes. The tool itself is an extraordinary one, so extraordinary that it sometimes addles us, making us act as if having powerful means justifies whatever ends they make possible.