Gray wolves once roamed across the United States from deserts to grasslands to forests and even the arctic tundra, but decades of overhunting and habitat loss had nearly driven them into extinction. In a remarkable conservation success story, however, the Endangered Species Act and other efforts helped gray wolf populations rebound.
Nevertheless, the iconic predators remain at a critical crossroads. The Trump administration's decision to strip wolves of their federal protections was widely viewed as a betrayal by the many people who have spent years — and billions of dollars — bringing them back from the brink of extinction.
One of the ways researchers and wildlife managers try to understand wolves' complex relationship with humans is by tracking their movements. A recent study, for example, followed a single wolf that traveled over 4,200 miles in 18 months, from Michigan through Wisconsin and Minnesota to North Dakota and then on into Manitoba, Canada. Researchers tracked the wolf by analyzing its howls and comparing them to a database of recorded calls.
For instance, the howls of different wolves carry different frequencies, and this information can be used to identify which individual is calling. However, the researchers also found that examining howls for their amplitude was equally important. By incorporating amplitude into their analysis, they improved the accuracy of howl identification by about 75 percent.
As wolves continue to reclaim their historic range, they're posing a new challenge for farmers and ranchers. A recent study showed that wolves may have a bigger impact on deer and elk herd size than other factors, such as weather conditions and disease.
