• High-Temporal Resolution Photography for Observing Riparian Area Use and Grazing Behavior

      Nichols, M.H.; Ruyle, G.B.; Dille, P.; Research Hydraulic Engineer, US Department of Agriculture (USDA)−Agricultural Research Service (ARS), Southwest Watershed Research Center; Professor, School of Natural Resources (SOC RANGE MANAGEMENT, 2017-07)
      Observation is a simple method of acquiring information and is a critical step in the scientific method for both developing and investigating testable hypotheses. Cameras have long played a role in observation, and as technology advances, new tools and methods for collecting, interrogating, and displaying large quantities of high-resolution images have evolved. We describe an automated digital time-lapse camera system and present an example field deployment to observe the temporal and spatial patterns of riparian use by humans and animals during a 3-mo period. We also describe software tools for image interrogation and visualization, as well as new information gathered through their use. The system was tested in 2014, in a 2.4-ha site within the ApacheSitgreaves National Forest in east central Arizona, United States where elk (Cervus elaphus nelsoni) and cattle grazed. Photographs were taken every 30 sec for 38 d, after which an electric fence was installed to restrict cattle access and the time step was increased to every 3 min. We observed that elk exhibited the unique behavior of standing in and traveling within the stream channel while grazing and tended to graze and lie in close proximity to the channel. Cattle drank from, but typically did not enter, the stream channel and tended to lie away from the channel. Recreational use by people had the distinct impact of dispersing elk from the riparian corridor. Zoomable time-lapse videos allowed us to observe that in contrast to the cattle, elk grazed while lying down. High-temporal resolution photography is a practical tool for observing phenomena that are important for local resource management. Published by Elsevier Inc. on behalf of The Society for Range Management.