The Old World ladybird Coccinella septempunctata has rapidly established itself as an abundant, widespread species throughout North America. Overwintering individuals of this species, and of native ladybirds, were collected from early season alfalfa in northern Utah during the period of initial establishment of the invader (1989 to 1999), and were measured for body size. Adult body size can var...

Invasive alien plant species negatively impact native plant communities by out-competing species or changing abiotic and biotic conditions in their introduced range. River systems are especially vulnerable to biological invasions, because waterways can function as invasion corridors. Understanding interactions of invasive and native species and their combined effects on river dynamics is essent...

Invasion biologists typically regard susceptibility of an invasive species to native predators as a fortuitous condition that increases biotic resistance to the invasion. The line of reasoning is that predation weakens the net impact of the invader and reduces its ability to displace native competitors. However, predation on invasives is a coupled interaction; every invader consumed also enhanc...

Biological invasions present a global threat to biodiversity. but oceanic islands are the systems hardest hit by invasions. Islands are generally depauperate in species richness, trophic complexity, and functional diversity relative to comparable mainland ecosystems. This situation results in low biotic resistance to invasion and many empty niches for invaders to exploit. It also results in isl...

Joseph E. Fargione* and David Tilman Department of Ecology, Evolution and Behavior, University of Minnesota, St Paul, MN 55108, USA *Correspondence and present address: Department of Biology, University of New Mexico, Albuquerque, NM 87131, USA E-mail: [email protected] Abstract Complementarity and sampling effects may both contribute to increased invasion resistance at higher diversity. We meas...

The calculations for the baseline model (monoculture evolution in the presence of moderate environmental variation) were presented in Snyder (2006). Here I show how to calculate the coevolved dispersal distances. To find the coevolved dispersal distances, we find the evolutionarily stable (ESS) annual dispersal distance as a function of the perennial dispersal distance, then find the ESS perenn...

Ecosystem managers face a difficult decision when managing invasive species. If they use aggressive practices to reduce invader abundances, they will likely reduce invaders' competitive impacts on natives. But it is often difficult or impossible to reduce invaders without damaging natives. So a critical question becomes: Which is worse for native biota, invaders or things done to control invade...

How do species coexist? A framework known as modern coexistence theory can ‘measure coexistence' by partitioning invasion growth rates into mechanisms, terms which correspond to classes of explanations for coexistence. There are several reasonable ways define each depending on exactly how a perturbed low density (the invader) is compared other that remain at their typical densities residents). ...

1. Themajority of experiments examining effects of species diversity on ecosystem functioning have randomlymanipulated species richness.More recent studies demonstrate that realistic species losses have dramatically different effects on ecosystem functioning than those of randomized losses, but these results are based primarily onmicrocosm experiments or modelling efforts. 2. We conducted a fie...

BACKGROUND Invasive species are a serious problem in ecosystems, but are difficult to eradicate once established. Predictive methods can be key in determining which areas are of concern regarding invasion by such species to prevent establishment [1]. We assessed the geographic potential of four Eurasian cyprinid fishes (common carp, tench, grass carp, black carp) as invaders in North America vi...