Long-term effects of fire on sage grouse habitat

Abstract

This study documented the long-term (> 10 years) impact of fire on sage grouse (Centrocercus urophasianus Bonaparte) nesting and brood-rearing habitats on the Upper Snake River Plain in southeastern Idaho. The habitat of the study area is primarily mountain big sagebrush (Artemisia tridentata vaseyana Rydb.)-grassland. Twenty different-aged burns were sampled from 1996 to 1997, ranging from wildfires which burned during the 1960s to prescribed fires set during the 1990s. Canopy coverage and height of vegetation, and relative abundance of invertebrates, were estimated at burned and unburned sites within burns. Fourteen years after burning, sagebrush had not returned to preburn conditions. No difference was detected in forb abundance between different-aged burns. Relative abundance of ants and beetles was significantly greater in the 1-year old burn category but had returned to unburned levels by 3-5 years postburn. No benefits for sage grouse occurred as a result of burning sage grouse nesting and brood-rearing habitats. Burning created a long-term negative impact on nesting habitat because sagebrush required over 20 years of postburn growth for percent canopy cover to become sufficient for nesting.