Active Tracking of Wolf Populations Using Autonomous Embedded Systems Design
The gray wolf population in Idaho has substantially increased since wolves were reintroduced into central Idaho and Yellowstone National Park in 1995-96. Although Idaho wolves were recently removed from the Endangered Species list, accurate monitoring of wolf population status and presence levels remains a critical task for natural resource managers. A number of monitoring systems and techniques are available but each has its limitations (e.g., cost, reliability, personnel safety). The Howl Box is a new, autonomous monitoring system recently prototyped by researchers at Montana Cooperative Wildlife Research Unit in Missoula. This electronic system periodically broadcasts a wolf howl recording and automatically records audio responses (e.g, howls from nearby wolves) to the howl stimulus. Early results indicated this system was effective for detecting wolf presence and, via audio spectral analysis, useful in identifying wolf individuals for detailed monitoring of population status. The Howl Box prototype, however, was composed of a netbook computer, external speaker and microphones, battery, and solar charging system and thus was relatively heavy, bulky, power-hungry, and expensive to construct and remotely deploy. Our project goal was to develop a wolf monitoring system based on the Howl box concept but lighter, smaller, more power-efficient, and less expensive. We used low-power, embedded electronic components including microcontrollers, MP3 encoder/decorders, and microSD card data storage to develop our system, the Howl Box 2.0 design was intended to allow one person, in one outing, to easily carry and deploy several of these monitoring units into rugged, remote monitoring sites where they would operate autonomously for 3-6 months or more without servicing. By reducing costs and increasing efficiencies, the Howl Box 2.0 should allow increased wolf monitoring intensity while reducing the need for airborne radio-tracking flights and other wolf monitoring techniques with associated personnel safety issues.