Colorado River Toads (also known as Sonoran Desert Toads) are widespread and common in much of southern and central Arizona, but ironically are now absent from much of their Colorado River distribution. Although they are large and conspicuous when they are active, they spend much of the year underground, making them difficult to study.  Department biologists have partnered with the Bureau of Reclamation to develop new, efficient methods for monitoring this species along the Colorado River.  This summer, we are evaluating the efficacy of using remote data loggers to listen for calling toads.  These units prove valuable due to their ability to collect data non-stop and allow busy Department biologists to effectively sample a larger area at lower cost.

Ryan P. O’Donnell, Wildlife Contracts Branch

Monitoring equipment used to detect Colorado River Toads.

Monitoring equipment used to detect Colorado River Toads.