Native range size and growth form in Cactaceae predict invasiveness and impact

By

Novoa, Ana
Kumschick, Sabrina, 1985-
Richardson, David
Rouget, Mathieu
Wilson, John

Type

Article

Date of Publication

2016

Original Publication

NeoBiota : advancing research on alien species and biological invasions

Volume

30

Pages

75-90

Subjects

Biological invasions , invasibility , invasiveness , Risk assessment , spread , weediness

Contributed by

Pensoft Publishers

Language

English

Published by

Sophia, Bulgaria Pensoft Publishers

Identifiers

DOI: https://doi.org/10.3897/neobiota.30.7253

 

Abstract

Many recent studies in invasion science have identified species traits that determine either invasiveness or impact. Such analyses underpin risk assessments and attempts to prioritise management actions. However, the factors that mediate the capacity of an introduced species to establish and spread (i.e. its invasiveness) can differ from those that affect the nature and severity of impacts. Here we compare those traits correlated with invasiveness with those correlated with impact for Cactaceae (“cacti”) in South Africa. To assess impact magnitude, we scored 70 cacti (35 invasive and 35 non-invasive species) using the Generic Impact Scoring System (GISS) and identified traits correlated with impact using a decision tree approach. We then compared the traits correlated with impact with those identified in a recent study as correlated with invasiveness (i.e. native range size and growth form). We found that there is a significant correlation between native range size and both invasiveness and impact. Cacti with larger native ranges were more likely to become invasive (p=0.001) and cause substantial impacts (p=0.01). These results are important for prioritising efforts on the management of cactus species. Understanding when and why impact and invasiveness are correlated (as they appear to be for Cactaceae) is likely to be an important area of future research in risk assessment.