Abstract
Urbanization is a major cause of biotic homogenization and habitat fragmentation for native communities. However, the role of urbanization on the success of biological invasions on a continental scale has yet to be explored. Urbanization may facilitate the establishment success of invasive species by minimizing niche differentiation between native and invaded ranges. In such cases, we might expect anthropogenic variables to have stronger influence on the geographic distribution of invasive compared to native populations. In this study, we use ecological niche modeling to define the distribution of non-native brown widow spider (Latrodectus geometricus) and three native black widows (L. hespersus, L. mactans, L. variolus) in North America and gauge the importance of urbanization on the geographic ranges of widows at a continental scale. We also quantify the geographic overlap of L. geometricus with each native widow to assess potential species and regions at risk of ecological impact. Consistent with our hypothesis, we find that the distribution of L. geometricus is strongly constrained to urban environments, while native widow distributions are more strongly driven by climatic factors. These results show that urbanization plays a significant role in facilitating the success of invasion, weakening the significance of climate on the realized niche in its invaded range.
Highlights
The Anthropocene is characterized by human impacts driving shifts in ecological processes, with biological invasions ranking as one of the major threats to biodiversity (Sala et al, 2000; Simberloff et al, 2013; Pievani, 2014; Russell and Kueffer, 2019; Pyšek et al, 2020)
Humans can aid in establishment success by sheltering species from climatic conditions that might lie beyond their climatic niche
We considered the role of urban environments, in addition to climate, in shaping the distribution of nonnative compared to native widows and compared geographic overlap of L. geometricus with each black widow species to assess potential areas and species at risk of ecological impact
Summary
The Anthropocene is characterized by human impacts driving shifts in ecological processes, with biological invasions ranking as one of the major threats to biodiversity (Sala et al, 2000; Simberloff et al, 2013; Pievani, 2014; Russell and Kueffer, 2019; Pyšek et al, 2020). Widow spiders of the genus Latrodectus (Araneae: Theridiidae) have historically been studied for their cannibalistic sexual behavior, but they are vital native predators of many arthropods in their natural ecosystems, including the invasive and venomous fire ant, Solenopsis invicta (Nyffeler et al, 1988; Andrade, 1996; Segoli et al, 2006, 2008a,b; Vetter and Isbister, 2008; Vassilevski et al, 2009; Yan and Wang, 2015) They are regarded as pests due to their potent venom and because several species are considered synanthropic, constructing webs on human-made structures. As a relatively well-documented introduced species in North America that relies on human development for shelter and dispersal, L. geometricus serve as a model for understanding the ecological impact of invasive generalist predators on native communities and the role of urbanization on their establishment and spread. We hypothesize that L. geometricus will have the strongest overlap with L. mactans
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
