Quantitative comparisons of distribution and abundance of exotic species in their native and non-native ranges represent a fi rst step when studying invaders. However, this approach is rarely applied particularly to tree species. Using biogeographical contrasts coupled with regional dispersal surveys, we assessed whether two exotic maple tree species, Acer negundo and Acer platanoides , can be ...

Invasive species are a major threat to global biodiversity and an important cause of biotic homogenization of ecosystems. Exotic plants have been identified as a particular concern because of the widely held belief that they competitively exclude native plant species. We examined the correlation between native and invasive species richness in 58 Ontario inland wetlands. The relationship between...

The temperate deciduous species Nothofagus glauca (Phil.) Krasser exhibits characteristics commonly found in fire-adapted vegetation, yet the role of fire in the evolutionary history of the vegetation in south-central Chile has not been well investigated. We examined the effects of a wildfire on early succession in a Nothofagus glauca forest in the Coastal Cordillera of south-central Chile by c...

Contrary to frequent characterisations, exotic species should not be identified as damaging species, species introduced by humans, or species originating from some other geographical location. Exotics are best characterised ecologically as species that are foreign to an ecological assemblage in the sense that they have not significantly adapted with the biota constituting that assemblage or to ...

Plant species assemblages, communities or regional floras might be termed 'saturated' when additional immigrant species are unsuccessful at establishing due to competitive exclusion or other inter-specific interactions, or when the immigration of species is off-set by extirpation of species. This is clearly not the case for state, regional or national floras in the USA where colonization (i.e. ...

The arrival of humans on oceanic islands has precipitated a wave of extinctions among the islands' native birds. Nevertheless, the magnitude of this extinction event varies markedly between avifaunas. We show that the probability that a bird species has been extirpated from each of 220 oceanic islands is positively correlated with the number of exotic predatory mammal species established on tho...

The spread of exotic earthworms (‘worming’) and rising temperatures are expected to alter the biological, chemical and physical properties of many ecosystems, yet little is known about their potential interactive effects. We performed a laboratory microcosm experiment to investigate the effects of earthworms (anecic, endogeic, epigeic, or all three together) and 4°C warming on soil water conten...

Exotic predators are a major threat to native wildlife in many parts of the world. Developing and implementing effective strategies to mitigate their effects requires robust quantitative data so that management can be evidence-based, yet in many ecosystems this is missing. Birds in particular have been severely impacted by exotic mammalian predators, and a plethora of studies on islands record ...

assiganga stream is an important tributary of bhagirathi river in central himalaya (india). the stream is characterized by heterogeneity in habitat and substratum features harboring diverse fish fauna. at present this stream is facing threat of being fragmented by the construction of two hydro-electric projects. present study aimed to study fish diversity and their habitat use in assiganga stre...

Question: What are the effects of fire in native shrubland communities and in pine plantations established in these shrublands? Location: Northern Patagonia, Argentina. Methods: We surveyed four sites in Chall–Huaco valley, located in northwest Patagonia. Each site was a vegetation mosaic composed of an unburned Pinus ponderosa plantation, a plantation burned in 1996, and an unburned matorral a...