Experimental reduction of a primary nest predator fails to decrease nest predation rates of sagebrush songbirds

Predator removal comprises one management strategy to increase the reproductive success of a prey species of concern, particularly within human-altered landscapes. The efficacy of such an approach, however, depends partly on the extent to which predation risk is additive or compensatory, which remains unknown for many systems. We experimentally reduced the local abundance of deer mice (Peromyscus maniculatus), a primary nest predator of three sagebrush-obligate songbirds (Brewer’s Sparrow [Spizella breweri], Sagebrush Sparrow [Artemisiospiza nevadensis], and Sage Thrasher [Oreoscoptus montanus]) during May ̶ August 2019 in western Wyoming, USA to assess whether nest predation risk was additive or compensatory and whether nest predator removal could comprise a potentially effective management tool. Deer mouse removal did not affect the daily nest survival of songbirds between experimental and control plots, despite a reduction of 68 ̶ 85% in deer mouse abundance within treatment areas. N...