How to translate text using browser tools
11 December 2019 Application of Ground-Based Lidar and Gap Intercept Measurements to Quantify a Shrub Configuration Metric within Greater Sage-Grouse Nesting Habitat
Khodabakhsh Zabihi, Kenneth L. Driese, Ginger B. Paige, Ann K. Hild
Author Affiliations +
Abstract

Vegetation composition (i.e., relative proportion of species) and configuration (i.e., horizontal and vertical arrangement of the plant components) in sagebrush-steppe ecosystems are fundamental determinants of the suitability of nesting habitat for Greater Sage-Grouse (Centrocercus urophasianus). The spatial arrangement of shrub and herbaceous canopy cover conceals Greater Sage-Grouse from predators and protects the nest from natural hazards, and gaps in vegetative cover provide escape routes for hens. Most sage-grouse habitat studies quantify vegetation composition, but few quantify habitat configuration at fine scales. We used ground-based lidar (light detection and ranging) data from Greater Sage-Grouse nesting habitat to test the applicability of a metric calculated from the traditional canopy gap intercept measurements to quantify shrub canopy configuration (shrub patchiness). Vegetation surveys were conducted on 30 randomly selected nest and non-nest sites (15 of each); we acquired high-resolution ground-based lidar data for 12 plots at 3 nest locations. Variation in canopy gap size was used as a metric to represent shrub configuration characteristics. We measured the variability in gap size among shrubs within lidar point cloud data sets using a lacunarity index at multiple scales. We measured variability of gaps from line transects by calculating the variance to mean-square ratio of gap size. Correlations (r) between measures of gap size variation from the 2 techniques ranged from 0.76 to 0.83 (r2 = 0.58–0.69). Our results support the use of canopy gap intercept measures to quantify configuration (patchiness) of shrub cover and thus complement vegetative composition metrics. Gap sizes were more variable at nest sites than at non-nest sites, suggesting that gap size variability may be a useful vegetative configuration metric to characterize sage-grouse nesting habitat. The fine-scale habitat metrics we evaluated provide a more refined tool for land managers to characterize local variation in wildlife habitat within shrubland ecosystems and can be derived from the existing gap intercept data.

© 2019
Khodabakhsh Zabihi, Kenneth L. Driese, Ginger B. Paige, and Ann K. Hild "Application of Ground-Based Lidar and Gap Intercept Measurements to Quantify a Shrub Configuration Metric within Greater Sage-Grouse Nesting Habitat," Western North American Naturalist 79(4), 500-514, (11 December 2019). https://doi.org/10.3398/064.079.0404
Received: 4 August 2018; Accepted: 30 April 2019; Published: 11 December 2019
RIGHTS & PERMISSIONS
Get copyright permission
Back to Top