Evidence of natal habitat preference induction within one habitat type

Abstract

Natal habitat preference induction (NHPI) is a mechanism for habitat selection by individuals during natal dispersal. NHPI occurs in wild animal populations, and evidence suggests it may be a common, although little studied, mechanism for post-dispersal habitat selection. Most tests of NHPI examine the influence of distinct, contrasting natal habitat types on post-dispersal habitat selection. We test the hypothesis that NHPI can occur within a single habitat type, an important consideration for habitat specialists. The Mount Graham red squirrel (Tamiasciurus hudsonicus grahamensis) is an endangered forest obligate restricted to a single mountain primarily within mixed-conifer forest. We test for NHPI by comparing intra-individual differences in natal and settlement habitat structure and composition to expected random pairwise differences. Dispersing juveniles appear to select settlement locations that are more similar to natal areas than expected in several forest structure and composition variables that include canopy cover and live basal area. Our results provide support for NHPI as a mechanism for post-dispersal habitat selection in habitat specialists that occupy a single vegetation community type.