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September 12, 2022

Line-transect distance sampling (LTDS) surveys are commonly used to estimate abundance of animals or objects. In terrestrial LTDS surveys of gopher tortoise (Gopherus polyphemus) burrows, the presence of ground-level vegetation significantly decreases detection of burrows of all sizes, but no field or analytical methods exist to control for spatially heterogeneous vegetation obstruction as a source of variation in detection. Here we propose the addition of a simple measurement of ground-level vegetation that serves as a covariate for the detection function. We present a Bayesian hierarchical model in which covariates burrow width and nearby vegetation height help to account for detection bias and improve precision of estimated density.

Citation Information

Publication Year 2022
Title Vegetation_LTDS
DOI 10.5066/P9B9DAFU
Authors Moore Clinton , Heather Gaya
Product Type Software Release
Record Source USGS Digital Object Identifier Catalog
USGS Organization Cooperative Research Units