title: Landscape corridors can increase invasion by an exotic species and reduce diversity of native species.
abstract: Landscape corridors are commonly used to mitigate negative effects of habitat fragmentation, but concerns persist that they may facilitate the spread of invasive species. In a replicated landscape experiment of open habitat, we measured effects of corridors on the invasive fire ant, Solenopsis invicta, and native ants. Fire ants have two social forms: polygyne, which tend to disperse poorly but establish at high densities, and monogyne, which disperse widely but establish at lower densities. In landscapes dominated by polygyne fire ants, fire ant abundance was higher and native ant diversity was lower in habitat patches connected by corridors than in unconnected patches. Conversely, in landscapes dominated by monogyne fire ants, connectivity had no influence on fire ant abundance and native ant diversity. Polygyne fire ants dominated recently created landscapes, suggesting that these corridor effects may be transient. Our results suggest that corridors can facilitate invasion and they highlight the importance of considering species' traits when assessing corridor utility.
authors.forename: Julian
authors.initials: J
authors.lastname: Resasco
authors.forename: Nick M
authors.initials: NM
authors.lastname: Haddad
authors.forename: John L
authors.initials: JL
authors.lastname: Orrock
authors.forename: DeWayne
authors.initials: D
authors.lastname: Shoemaker
authors.forename: Lars A
authors.initials: LA
authors.lastname: Brudvig
authors.forename: Ellen I
authors.initials: EI
authors.lastname: Damschen
authors.forename: Joshua J
authors.initials: JJ
authors.lastname: Tewksbury
authors.forename: Douglas J
authors.initials: DJ
authors.lastname: Levey
mesh_terms: D000818:Animals; D001000:Ants; D001522:Behavior, Animal; D044822:Biodiversity; D003710:Demography; D058865:Introduced Species; D013022:South Carolina; D013045:Species Specificity