Visibility and Vigilance: Behavior and Population Ecology of Uinta Ground Squirrels (Spermophilus Armatus) in Different Habitats

Difficulties in Monitoring Conspecifics Mediate the Effects of Visual Obstruction on the Level and Synchronization of Vigilance

“…Visual obstruction can thus interfere with vigilance and increase predation risk (Lima, 1987). Observational studies with naturally-occurring visual obstacles and experimental studies, in which the field of view is altered by the researchers, have typically documented an increase in vigilance with visual obstruction (Lima, 1992;Arenz and Leger, 1997;Lima and Bednekoff, 1999;Blumstein and Daniel, 2003;Whittingham et al, 2004;Butler et al, 2005;Ebensperger and Hurtado, 2005;Fernández-Juricic et al, 2005;Devereux et al, 2006;Bednekoff and Blumstein, 2009;Iribarren and Kotler, 2012) although there are exceptions (Lima, 1987;Foster-McDonald et al, 2006;Hannon et al, 2006;Hall et al, 2013).…”

Restoring habitat for the northern Idaho ground squirrel (Urocitellus brunneus brunneus): Effects of prescribed burning on dwindling habitat

“…However, the prescribed burn decreased BURN understory height by 16 cm, which resulted in levels similar to CONTROL units. Understory height in CONTROL units could allow a ground squirrel to utilize both antipredator strategies: cover and visibility (Hannon et al, 2006). In sand shinnery oak habitat, visual obstruction was significantly reduced one year post-burn but recovered to control levels within five years post-burn (Harrell et al, 2001).…”

How will the greening of the Arctic affect an important prey species and disturbance agent? Vegetation effects on arctic ground squirrels

“…Secondly vegetation stature can affect the type of predator, predator foraging strategy (Gillis et al 2005a), or predator density. Tall vegetation may, however, also have positive effects by providing cover for foraging herbivores (Hannon et al 2006).…”

“…This variety of vegetation effects may have complex interplays. In Uinta ground squirrels (Urocitellus armatus, Kennicott 1863), shrubs may have antagonistic effects as both visual obstructions and as beneficial cover, with the result that effects on forage are likely to determine the net effect on the squirrels (Hannon et al 2006). Understanding the contributions of these different roles of vegetation stature and forage to the distribution and local abundance of alpine and arctic small herbivores is key to understanding the likely impacts of future vegetation change.…”