Journal Article

Characteristics of shrub morphology on nest site selection of Greater Sage-Grouse in high-elevation sagebrush habitat/Caracteristicas de la morfologia de arbustos en la seleccion de sitios de anidacion en el urogallo Centrocercus urophasianus en habitat de Artemisia spp. a elevacion alta

Cutting, Kyle A, Schroff, Sean R, Mcnew, Lance B, Frisina, Michael R, Sowell, Bok F, Carr, Craig A

2018

Overview

Selection of nest sites directly influences reproductive success for Greater Sage-Grouse (Centrocercus urophasianus); thus, regional evaluation of how this species selects nest sites is necessary for effective habitat management. We evaluated fine-scale nest site selection of Greater Sage-Grouse in the Centennial Valley of southwest Montana. We conducted vegetation surveys at nest sites (n = 90) of radio-tagged Greater Sage-Grouse and paired random locations across 2 breeding seasons (2014-2015). The majority of nests were located under mountain big sagebrush (Artemisia tridemata ssp. vaseyana), three-tip sagebrush (A. tripartita), and basin big sagebrush (A. tridentata ssp. tridenlata) shrubs. We used generalized linear models and information theory to evaluate competing hypotheses about nest site selection. Our top model indicated that nest site selection was primarily associated with nest shrub morphological characteristics and cover provided by the nest shrub. Mountain big sagebrush and three-tip sagebrush provided twice the amount of lateral cover that basin big sagebrush shrubs provided. Our results suggest that herbaceous cover was unimportant at fine scale nest site selection of Greater Sage-Grouse in our study area. Managers should focus on conserving large intact stands of mountain big sagebrush and three-tip sagebrush habitats because they provided the most lateral cover and supported the majority of nest sites. Received 2 June 2017. Accepted 30 January 2018. Key words: Artemisia spp., Centrocercus urophasianus. Greater Sage-Grouse, herbaceous cover, nest site selection, sagebrush, shrub morphology. La seleccion de sitios de anidacion influencia de manera directa el exito reproductivo del urogallo Cenfrocercus urophasianus. Por ello, necesitamos una evaluacion regional de como seleccionan sitios de anidacion para lograr un manejo efectivo de habitat. Evaluamos la seleccion de sitios de anidacion del urogallo a escala fina en el Centennial Valley en cl suroeste de Montana. Hicimos reconocimientos de la vegetacion en sitios de anidacion (n = 90) de urogallos marcados con transmisores de telemetria y en localidades aleatorias pareadas a lo largo de dos temporadas reproductivas (2014-2015). La mayoria de los nidos fueron encontrados debajo de los arbustos Artemisia tridentata ssp. vaseyana, A. tripartita y A. tridentata ssp. tridentata. Utilizamos modelos lineales generales y teoria de la informacion para evaluar la competencia entre hipotesis acerca de la seleccion de nidos. Nuestro modelo con mejor soporte se asocia principalmente con caracteristicas morfologicas y la cobertura provista por el arbusto de anidacion. Los arbustos de Artemisia tridentata vaseyana y A. tripartita proveen el doble de la cantidad de cobertura lateral que el provisto por A. tridentata tridentata. Nuestros resultados sugieren que la cobertura herbacea no es importante a escala fina en la seleccion de sitios nido de este urogallo en nuestra area de estudio. Quienes manejan estos habitats deben enfocarse en parcelas grandes e intactas de Artemisia tridentata vaseyana y A. tripartita porque proveen la mayor cobertura lateral y dan soporte a la mayoria de los sitios de anidacion. Palabras clave: Artemisia spp., Centroeercns urophasianus, cobertura herbacea, morfologia de arbustos, seleccion de sitios nido.

• Publisher: Wilson Ornithological Society
• Subject: Big sagebrush / Habitat selection / Nest building / Ornithological research / Sage grouse / Sagebrush / Sagebrushes