Different climatic envelopes among invasive populations may lead to underestimations of current and future biological invasions

Abstract

AimWe explore the impact of calibrating ecological niche models (ENMs) using (1) native range (NR) data versus (2) entire range (ER) data (native and invasive) on projections of current and future distributions of three Hieracium species. Location H. aurantiacum , H. murorum and H. pilosella are native to Europe and invasive in Australia, New Zealand and North America.Methods Differences among the native and invasive realized climatic niches of each species were quantified. Eight ENMs in BIOMOD were calibrated with (1) NR and (2) ER data. Current European, North American and Australian distributions were projected. Future Australian distributions were modelled using four climate change scenarios for 2030.Results The invasive climatic niche of H. murorum is primarily a subset of that expressed in its native range. Invasive populations of H. aurantiacum and H. pilosella occupy different climatic niches to those realized in their native ranges. Furthermore, geographically separate invasive populations of these two species have distinct climatic niches. ENMs calibrated on the realized niche of native regions projected smaller distributions than models incorporating data from species' entire ranges, and failed to correctly predict many known invasive populations. Under future climate scenarios, projected distributions decreased by similar percentages, regardless of the data used to calibrate ENMs; however, the overall sizes of projected distributions varied substantially. Main conclusionsThis study provides quantitative evidence that invasive populations of Hieracium species can occur in areas with different climatic conditions than experienced in their native ranges. For these, and similar species, calibration of ENMs based on NR data only will misrepresent their potential invasive distribution. These errors will propagate when estimating climate change impacts. Thus, incorporating data from species' entire distributions may result in a more thorough assessment of current and future ranges, and provides a closer approximation of the elusive fundamental niche.

Predicting the potential distribution of an endangered cryptic subterranean mammal from few occurrence records

“…Soil characteristics and vegetation have been shown to be important to this species (Jackson et al, , 2008. We selected the set of bioclimatic predictor variables that were likely to summarise temperature and moisture availability, which are important for predicting distributions (Beaumont et al, 2009). The bioclimatic predictor variables included: temperature seasonality; maximum temperature of warmest month; minimum temperature of coldest month; mean temperature of warmest month; annual precipitation; precipitation seasonality; precipitation of wettest quarter; and precipitation of warmest quarter.…”

In their native range, invasive plants are held in check by negative soil-feedbacks

“…Increased global trade and traffic, as well as species shifts as a result of global warming are major drivers of the introduction process. Results from recent studies suggest that plants that shift ranges towards higher latitudes and altitudes also include potential invaders (Engelkes et al 2008, Beaumont et al 2009, van Grunsven et al 2010.…”

The House Crow (Corvus splendens): A Threat to New Zealand?

“…This use of ecological niche modeling technique is similar to other studies for predicting the potential geographic distribution of a range of plant and animal invasive species such as mammals [50], birds [9,51], plants [52,53], amphibians and reptiles [54,55], insects [56] and fish [57]. Invasive bird species have been shown to have a higher success of establishment and spread in novel areas if the climate match is similar to that of the native range [58][59][60][61].…”