title: Invasive plant species alters consumer behavior by providing refuge from predation.
abstract: Understanding the effects of invasive plants on native consumers is important because consumer-mediated indirect effects have the potential to alter the dynamics of coexistence in native communities. Invasive plants may promote changes in consumer pressure due to changes in protective cover (i.e., the architectural complexity of the invaded habitat) and in food availability (i.e., subsidies of fruits and seeds). No experimental studies have evaluated the relative interplay of these two effects. In a factorial experiment, we manipulated cover and food provided by the invasive shrub Amur honeysuckle (Lonicera maackii) to evaluate whether this plant alters the foraging activity of native mammals. Using tracking plates to quantify mammalian foraging activity, we found that removal of honeysuckle cover, rather than changes in the fruit resources it provides, reduced the activity of important seed consumers, mice in the genus Peromyscus. Two mesopredators, Procyon lotor and Didelphis virginiana, were also affected. Moreover, we found rodents used L. maackii for cover only on cloudless nights, indicating that the effect of honeysuckle was weather-dependent. Our work provides experimental evidence that this invasive plant species changes habitat characteristics, and in so doing alters the behavior of small- and medium-sized mammals. Changes in seed predator behavior may lead to cascading effects on the seeds that mice consume.
authors.affiliation: Department of Natural Sciences, Life University, 1269 Barclay Circle, Marietta, GA 30060, USA. hpdutra@yahoo.com
authors.forename: Humberto P
authors.initials: HP
authors.lastname: Dutra
authors.forename: Kirk
authors.initials: K
authors.lastname: Barnett
authors.forename: Jason R
authors.initials: JR
authors.lastname: Reinhardt
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Marquis
authors.forename: John L
authors.initials: JL
authors.lastname: Orrock
mesh_terms: D000818:Animals; D048293:Didelphis / Q000502:physiology*; D017753:Ecosystem; D005247:Feeding Behavior; D020387:Food Chain; D058865:Introduced Species; D031239:Lonicera / Q000254:growth & development*; D008923:Missouri; D010542:Peromyscus / Q000502:physiology*; D011821:Raccoons / Q000502:physiology*; D014887:Weather