Cookies on CABI

Like most websites we use cookies. This is to ensure that we give you the best experience possible.


Continuing to use  means you agree to our use of cookies. If you would like to, you can learn more about the cookies we use.

Search this site
Sign up for the CABI e-zine Newsletter
Improving lives by solving problems in agriculture and the environment

Action on Invasives

Invasive species impact the livelihoods of the rural poor who are dependent on natural resources for income and food security. CABI is implementing an ambitious programme to address this complex issue. We are working with local, national and regional partners, and across agriculture, environment and other sectors, to create an integrated and sustainable framework for addressing the problem of invasive species, generating growth, creating jobs and helping to reduce poverty.

Project Overview

So, what's the problem

Increased global trade and travel, as well as climate change, has an unfortunate side effect – the rapid spread of invasive species. Intentionally or accidentally imported plants, insects and pathogens can all have an adverse impact on human, animal, agricultural and environmental health.

Invasive species are estimated to cost the global economy over US$1.4 trillion annually. They disregard national borders and unmanaged, can be global in their impact. They undermine investments in development, and significantly affect the livelihoods of vulnerable rural communities who depend on natural resources and ecosystem health for their survival.

Unappreciated by many, the burden of invasive species weighs particularly heavily on the poorest and most vulnerable. Throughout Southeast Asia for example, invasive species cost at least US$33 billion annually (US$55 per capita), reducing GDP by up to 5%.

Invasions are often not detected or responded to in the early stages, leading to their rapid establishment and spread. This makes control more difficult and less cost effective, and is generally due to a piecemeal and uncoordinated approach without appropriate plans and policies. Often there is inadequate collaboration between key national stakeholders (especially agriculture, trade and environment sectors), and insufficient consideration of social and gender issues at the community level.

What is this project doing?

Our overall objective is to protect and restore agricultural and natural ecosystems and resources, increase crop yields, improve health, protect trade and reduce the degradation of protected areas. Ultimately this will improve the livelihoods of 50 million poor rural households who are affected by invasive species in Africa and Asia.

The programme follows the globally adopted three-tier approach of prevention, early detection, eradication/ containment and finally the control of established species followed by restoring damaged ecosystems. We are developing local, national and regional capacity to implement this approach to:

1. Strengthen links and partnerships between stakeholders to set priorities, deliver action plans, and inform and influence policy

2. Identify and validate technical solutions to prevent and control invasive species, in collaboration with national and international partners

3. Scale up implementation of validated management approaches by working and communicating with affected communities

4. Provide information, knowledge and tools for practical decision making by a wide range of users

The programme builds on the collaborative infrastructure established through CABI’s Plantwise programme which supports farmers with plant health advice and strengthens national plant health systems.


Initial focus species are Fall armyworm, Parthenium and tomato leaf miner. We have supported national planning in Ghana and Pakistan, and have produced an Evidence Note on Fall armyworm (commissioned by DFID) that has been widely referred to.

Control methods, including classical biological control for both Parthenium and Fall armyworm, are being tested and we are identifying priority pest risks species in Kenya that we can either prevent or detect. Baseline surveys of farmers’ practices, knowledge and losses have been completed.

We have also conducted major communication campaigns to promote awareness and management of Fall armyworm (Ghana, Uganda, Zambia) and Parthenium (Pakistan); reaching large numbers of people through multiple communication channels.

Our free Invasive Species Compendium is also being substantially enhanced through the programme. It will include specialised portals for high priority species, a horizon scanning tool which has been launched and we are soon releasing a pest risk analysis tool which we are training National Plant Protection Organisations on who contributed to its design.

We would soon like to expand the programme to additional countries and species in South Asia and Africa.

Our work in the news from the BBC and SciDev.

The team

Project Manager

Staff image of Roger Day

Roger Day  Programme Executive, Action on Invasives

Canary Bird
673 Limuru Road
PO Box 633-00621
T +254 20 2271000

Project team

Staff image of Julien Godwin

Julien Godwin

Programme Support Manager, Action on Invasives

Staff image of Abdul Rehman

Abdul Rehman

Deputy Director Programme

Staff image of Katherine Cameron

Katherine Cameron

Knowledge Management Programme Manager

Staff image of Monica  K. Kansiime

Monica K. Kansiime

Scientist - Agricultural Economist

Staff image of Marc Kenis

Marc Kenis

Head Risk Analysis and Invasion Ecology

Staff image of Ivan  Rwomushana

Ivan Rwomushana

Senior Scientist, Invasive Species Management

Staff image of Claire Curry

Claire Curry

Project Manager

Related publications CABI book shop

R.Day, J.Burgoyne, W.Coles, M.Hirschfeld, D.Reid, R.Winks, D.Rangi (2018) Invasive Species: The hidden threat to sustainable development

P.Abrahams, M.Bateman, T.Beale, V.Clottey, M.Cock, Y.Colmenarez, N.Corniani, R.Day, R.Early, J.Godwin, J.Gomez, P.Gonzalez Moreno, S.T. Murphy, B.Oppong-Mensah, N.Phiri, C.Pratt, S.Silvestri, A.Witt (2017) Fall Armyworm Evidence Note September 2017 

P.Abrahams, M.Bateman, T.Beale, V.Clottey, M.Cock, Y.Colmenarez, N.Corniani, R.Day, R.Early, J.Godwin, J.Gomez, P.Gonzalez Moreno, S.T. Murphy, B.Oppong-Mensah, N.Phiri, C.Pratt, S.Silvestri, A.Witt (2017) Fall Armyworm Evidence Note (Summary version) September 2017

Corin F. Pratt, Kate L. Constantine, Sean T. Murphy. (2017) Economic impacts of invasive alien species on African smallholder livelihoods. Global Food Security

Witt, A., Kiambi, S; Beale., T. and van Wilgen, B.W. A preliminary assessment of the extent and potential impacts of alien plant invasions in the Serengeti-Mara ecosystem, East AfricaKoedoe - African Protected Area Conservation and Science 59(1) · May 2017 DOI: 10.4102/koedoe.v59i1.1426

Ross T. Shackleton, Arne B. R. Witt, Winnie Nunda, David M. Richardson (2017) Chromolaena odorata (Siam weed) in eastern Africa: distribution and socio-ecological impacts. Biological Invasions. April 2017, Volume 19, Issue 4, pp 1285–1298

P. Abrahams, T. Beale, M. Cock, N. Corniani, R. Day, J. Godwin, S. Murphy, G. Richards & J. Vos. Fall armyworm inception report (April 2017)

Ross T Shackleton, Arne BR Witt, Winnifred Aool & Corin F Pratt (2017) Distribution of the invasive alien weed, Lantana camara, and its ecological and livelihood impacts in eastern Africa. African Journal of Range & Forage Science 

Shackleton, R.T., Witt, A., Piroris, F.M., van Wilgen, B.W. Distribution and socio-ecological impacts of the invasive alien cactus Opuntia stricta in eastern Africa. Biological Invasions · May 2017 DOI: 10.1007/s10530-017-1453-x

Cock, M.J.W.; Day, R.K.; Hinz, H.L.; Pollard, K.M.; Thomas, S.E.; Williams, F.E.; Witt, A.B.R.; Shaw, R.H. (2016) The impacts of some classical biological control successes. CAB Reviews 10(42), 58 pp. doi:10.1079/pavsnnr201510042

Book chapter: Arne Witt
Impact of Biological Invasions on Ecosystem Services: Use of Non-native Species for Poverty Alleviation in Developing Economies

Witt, A. (2017) Guide to the naturalized and invasive plants of Southeast Asia

Witt, A. (2017) Guide to the naturalized and invasive plants of Laikipia

Witt, A. (2017) Guide to the naturalized and invasive plants of Eastern Africa