Elk forage response to prescribed fire in Boyes meadow, Prairie Creek Redwoods State Park, California

Abstract

Prescribed fire should increase plant and forage biomass for herbivores in meadows, but the response is likely to be influenced by environmental conditions. Across 15 years prescribed fires occurred every two to four years in September in Boyes meadow, Humboldt County, California. We measured the presence or absence of prescribed fires in September, climatic conditions one month later, Roosevelt elk (Cervus elaphus roosevelti) abundance, and the biomass of elk forage in January. From analysis of a linear mixed effects model we found that prescribed fires increased forage biomass the first January post-burn and even more so a year after the burn. Forage biomass two years post-burn decreased but was still more than three to four years post-burn. October precipitation had a positive effect on forage biomass but we detected no influence from low temperature in October or elk abundance. Given that prescribed fire increased elk forage biomass two years later, continuing to burn Boyes meadow on a three to four year rotation is suggested.

Keywords

• california
• forage biomass
• herbivory
• precipitation
• temperature