A national strategic framework for the management of the family Cactaceae in South Africa

A national strategic framework for the management of the family Cactaceae in South Africa
Haylee Kaplan1, Hildegard Klein2, John R. Wilson1,3, Lesley Henderson2, Helmuth Zimmerman4, Philip Ivey1, David M. Richardson3, Phetole Manyama1Brian W. van Wilgen3, Ana NOVOA1,3
1Invasive Species Programme, South African National Biodiversity Institute, Kirstenbosch Research Centre, Claremont, South Africa;
2Agricultural Research Council – Plant Protection Research Institute;
3Centre for Invasion Biology, Department of Botany and Zoology, Stellenbosch University;
4Helmuth Zimmermann & Associates (Central), Pretoria, South Africa

Cacti (Cactaceae) are among the most widespread and damaging groups of invasive plants in South Africa. There are currently 35 cactus species known to be naturalised or invasive in South Africa, most of which cause considerable ecological, social and economic impacts. However, despite a long history of controlling cactus invasions, management to date has lacked effective cohesive strategic planning at a national scale. In response to this need, a South African Cactus Working Group (SACWG) was established in 2013 to develop guidelines for a national strategic framework. This paper summarizes the status of cactus invasions and management in South Africa and presents the national strategic framework developed by the SACWG. The overarching aim of the framework is to reduce the negative impacts of cacti to a point where their benefits significantly outweigh the losses. Four strategic objectives designed to achieve the desired outcome are proposed: 1) all invasive and potentially invasive cactus species should be prevented from entering the country, 2) new cases of naturalisation of cactus species must be rapidly detected and eradicated, 3) the impacts of invasive cacti must be reduced and contained, and 4) socio-economically useful cacti (both invasive and non-invasive species) must be utilized sustainably and the risk of further negative impacts must be minimized. A decision-support tool for guiding assignment of species to each of the above-mentioned objectives is described. Indicators for evaluating the progress of strategic management of cacti are discussed in the context of the National Status Report.