ORIGINAL PAPER Relationship between the presence of House Sparrows (Passer domesticus) and Neotropical bird community structure and diversity Ian MacGregor-Fors Æ Lorena Morales-Pe ´rez Æ Javier Quesada Æ Jorge E. Schondube Received: 28 February 2008 / Accepted: 12 January 2009 / Published online: 29 January 2009 Ó Springer Science+Business Media B.V. 2009 Abstract Invasive exotic species pose an important threat to biodiversity worldwide. However, there is little information on the effects that specific exotic bird species have on native biota. The House Sparrow is an excellent ecological model to evaluate the effect that an invasive exotic species has on native bird communities. Our study describes the relationship of the presence and abundance of House Sparrows with the structure, diversity, and composition of native bird communities in West Mexico. We used two approaches to compare House Sparrow invaded and non-invaded bird communities: (1) at a small geo- graphic-scale that allowed us to evaluate shifts in avian communities with presence of the House Sparrow under similar environmental conditions; and (2) at the landscape-level to evaluate the effect of this species under a scenario of greater environ- mental heterogeneity. Results from both approaches show that areas invaded by House Sparrows have heavily-dominated avian communities with low species richness, while non-invaded areas exhibit highly-even and species-rich bird communities. Spe- cies turnover analysis indicates that the decrease in the number of bird species in House Sparrow invaded areas is caused by species loss, rather than a shift in species composition. Our results indicate that the invasion of an area by the House Sparrow, through synergistic interactions with human activities, deter- mines the composition, structure, and diversity of native bird communities. Keywords House Sparrow Á Exotic species Á Human-altered ecosystems Á Urban ecology Á Bird communities Á Biodiversity Introduction The anthropogenic introduction of exotic species represents a significant component of global change (Zaret and Paine 1973; Vitousek et al. 1997; Smith and Knapp 2001). Successful invasions of exotic species often cause major changes to native ecosys- tems (Wilson and Belcher 1989; Hawkes et al. 2005; Gritti et al. 2006). Exotic species can affect native biota at different ecological levels, modifying spe- cies population dynamics, community structure, or even ecosystems level processes (Kalinoski 1975; Gowaty 1984; Fritts and Rodda 1998). Humans have I. MacGregor-Fors (&) Á L. Morales-Pe ´rez Á J. Quesada Á J. E. Schondube Centro de Investigaciones en Ecosistemas, Universidad Nacional Auto ´noma de Me ´xico, Campus Morelia, Apartado Postal 27-3, 58190 Morelia, Michoaca ´n, Me ´xico e-mail: ian@oikos.unam.mx J. Quesada Institut Catala ` d’Ornitologia. Museu de Cie `ncies Naturals de la Ciutadella, Passeig Picasso s/n, 08003 Barcelona, Spain 123 Biol Invasions (2010) 12:87–96 DOI 10.1007/s10530-009-9432-5