Vegetation phenology can be captured with digital repeat photography and linked to variability of root nutrition inHedysarum alpinum

Abstract

AbstractQuestionCan repeat (time‐lapse) photography be used to detect the phenological development of a forest stand, and linked to temporal patterns in root nutrition forHedysarum alpinum(alpine sweetvetch) an important grizzly bear food species?LocationEastern foothills and front ranges of theRockyMountains inAlberta,Canada. The area contains a diverse mix of mature and young forest, wetlands and alpine habitats.MethodsWe deployed six automated cameras at three locations to acquire daily photographs at the plant and forest stand scales. Plot locations were also visited on a bi‐weekly basis to record the phenological stage ofH. alpinumand other target plant species, as well as to collect a root sample for determination of crude protein content.ResultsRepeat photography and image analysis successfully detected all key phenological events (i.e. green‐up, flowering, senescence). Given the relation between phenology and root nutrition, we illustrate how camera data can be used to predict the spatial and temporal distribution and quality of a key wildlife resource.ConclusionsRepeat photography provides a cost‐effective method for monitoring vegetation development, food availability, and nutritional quality at a forest stand scale. Since wildlife responds to the availability and quality of their food resources, detailed information on changes in resource availability helps with land‐use management decisions and furthers our understanding of grizzly bear feeding ecology and habitat selection.