Used as an effective method of controlling invasive species, biological control (or biocontrol) is the term given to the use of living organisms for controlling pests and invasive species. It can provide an effective, environmentally-friendly and cost-efficient way of controlling pest populations, helping to restore crop yields and farmer’s profits. However a recent study, focussing on invasive cassava mealybugs, has shown that biocontrol can also have some surprising knock-on effects.
A conversation with Dr Arne Witt
The recent outbreak of Ebola virus disease in West Africa made headline news around the world. During the outbreak this fatal disease, endemic to parts of Central and West Africa, rapidly spread from Guinea, Sierra Leone, and Liberia to other countries in the region such as Nigeria, Mali and Senegal and then further afield to the USA, UK and Spain, mainly through infected health workers. This prompted decisive action from governments around the world and led to the implementation of strict controls at most national points of entry – as a result of this action and increased awareness, the further spread of this disease was effectively halted. No new infections have been reported for a number of months now but the cost has been significant – more than 10,000 people lost their lives, mainly in Guinea, Sierra Leone, and Liberia. However, it is highly probable that without significant interventions the costs could have been far higher. For example, the outbreak of bubonic plague or Black Death in Europe in the 17th century resulted in the death of 34 million people. The accidental introduction of potato blight, a crop disease which affects potatoes, from the Americas to Ireland in the mid-1800s contributed to the starvation of about 1 million people. Rinderpest, a disease affecting livestock was accidentally introduced to Africa from Asia in the late 19th century resulting in the deaths of, it is claimed, a third of the human population of what is now Ethiopia and two-thirds of the Maasai, an ethnic group of pastoralists in East Africa who are totally dependent on livestock. We may ask what Ebola, potato blight and rinderpest have in common – well obviously they have all have had a devastating impact on humanity but what binds them all together is that they are all INVASIVE ALIEN SPECIES (IAS). Fortunately, due to concerted efforts by a range of agencies rinderpest has been eradicated from the planet but as a result of increased trade, travel and tourism more and more species are being moved around the world and many are establishing and are continuing to have devastating impact on livelihoods. Continue reading