Have you ever wondered where a stream starts? Well, the answer is much more complicated than you might think! Stream length changes both seasonally and even year-to-year. In fact, here in Alabama over 50% of our mapped streams dry on a regular basis! Some years, like during the 2016 drought, even more than half of our streams go dry. Delaney Peterson, PhD student in our lab, is mapping flowing stream length on a seasonal basis at the Tanglewood Biological Station. To do this, Delaney and a small army of volunteers (see picture below) walk all of Tanglewood’s headwater streams and take measurements every 100 meters.