Estimating Nest Density When Detectability is Incomplete: Variation in Nest Attendance and Response to Disturbance by Western Meadowlarks

The condor

Matthew D. Giovanni¹ 

关键词: Bayesian hierarchical model;    detection error;    false-negative errors;    nest attendance;    nest density;    Sturnella neglecta;    Western Meadowlark;   

DOI  :  10.1525/cond.2011.100076

学科分类：动物科学

来源: Central Ornithology Publication Office

【 摘 要 】

Abstract. Researchers commonly model nest density as a function of ecological variables, but nests, like birds, can be undetected while present. In the Nebraska Sandhills in 2007, we used the rope-drag method on previously located Western Meadowlark (Sturnella neglecta) nests to model nest-detection error and nest density. Detecting nests by rope dragging (commonly used for nests of grassland birds) is conditional on two primary sources of nest availability, adults attending nests and adults flushing from nests in response to disturbance from the rope, the behavioral cue necessary for nest detection. On the basis of our trials with rope dragging, the probability of adults attending nests was 0.46. The probability of trials eliciting flight responses from adults was 0.19, indicating that observed estimates of nest density were subject to detection error and negatively biased. We compared our ability to detect differences in nest densities between two habitat types with a statistical power analysis, using (...

【 授权许可】

CC BY