Impacts of farming intensification on wildlife and ecosystem health
©Ding Chang-Qing French white pigs cross bred with local Beninese variety for better meat and natural resistance to disease - ©FAO/ K. Pratt Sampling farmed wild bird in Poyang
©Scott Newman Farmed swan geese with poultry
At a recent meeting, FAO experts voiced concern that wildlife species are increasingly at risk from the expansion and intensification of agricultural production, which appropriates habitat and exposes wildlife and livestock to one another’s diseases. In addition, wildlife farming is also expanding, bringing wild animals’ novel pathogens into contact with other animals and humans, posing a direct risk to animal health and global human health.
Scott Newman and Lindsey McCrickard, wildlife veterinarians representing FAO’s Animal Health Service, shared these perspectives during the first joint conference of the Wildlife Disease Association and the European Wildlife Disease Association, which was held in Lyon, France, during the last week of July. FAO participated as co-convener of the Scientific Task Force on Wildlife and Ecosystem Health, a partnership on the issue among UN agencies, multi-lateral environmental agreements (MEAs), NGOs and civil society organizations from a variety of professions.
Feeding the world in 2050
According to FAO, the challenge of the next few decades is to sustainably increase animal and crop production to feed a rapidly expanding global population, which will mean one-third more mouths to feed by 2050. In many cases, the intensification of animal production entails putting animals into close contact with one another, sometimes in unhealthy environments. These animals, often stressed, have weakened immune systems, allowing pathogens to take hold. In rare cases, these pathogens can adapt to pass more easily from animal to animal, and even to different species. As the quantity of pathogens in circulation increases, so do the risks of adaptation and change. These adaptations or mutations could create a pathogen with the potential to spread quickly from animal – animal and even infect humans, sparking a pandemic. H5N1 highly pathogenic avian influenza is just one example of these rapidly changing pathogens of animal origin. More than 60 percent of the emerging diseases affecting humans have an animal origin, and of these, 75 percent come from wildlife.
Farming intensification can have great benefits, such as increasing food production, generating economic growth, lowering prices and thus improving food security. The potential negative impacts of unsustainable intensification include:
- Decreased genetic diversity of animals. Since industrial systems favor a single or a few select breeds of animals, biodiversity is lost. This results in lowered resilience to disease if one breed is highly susceptible to a given pathogen;
- Habitat loss and environmental damage due to animal waste or chemicals being dispersed into the environment;
- Overexploitation of soils and appropriation of increasing tracts of land to produce feed for animals and food to sustain the human population;
- Exacerbation of the effects of climate change.
Increasing agricultural production in a sustainable way
While increasing agricultural production is necessary to meet the world’s growing need for food – especially meat – this must be achieved in a sustainable way to avoid creating imbalances in ecosystems that put animal and human health at risk. The measures that can help reach this goal include:
- Using integrated pest management to protect crops and livestock from disease, thereby minimizing the use of insecticides that can harm the environement. IPM includes using natural predators (such as bats) to keep potentially damaging insect populations at acceptable levels;
- Incorporating natural land areas into agricultural land areas to preserve the local ecosystems;
- Rotating the planting of fields and rotating livestock grazing areas, which allows forage to recover, thus protecting against weeds and undesirable plant species. This also encourages soil retention and reduces the compacting of soils by livestock;
Carefully managed and sustainable farming increases using these and other elements of conservation agriculture have been shown to increase livestock production, by providing better forage, caring for animal welfare and health and rotating the source of fertilizer for fields.
SARS outbreak is one major warning sign
Despite recent global crises triggered by zoonotic diseases -- those that can pass between animals and humans – the alarm bells are quickly forgotten and risky practices are taken up again. For example, in the aftermath of the global health crisis triggered by severe acute respiratory syndrome (SARS) in 2003, there was a decrease in farming and consumption of civets, a cat-like mammal prized in some Asian cultures for the flavor of their meat, their uses in traditional medicines and even their role in producing a coffee delicacy called kopi luwak, made from beans that have passed through a civet’s digestive system.
SARS sickened more than 8000 people worldwide in a very short time, and became a pandemic when it quickly spread from Hong Kong to 23 other countries. More than 770 people died from SARS before the disease outbreak was brought under control. Investigation later indicated that farmed civets, brought to traditional live animal markets in Guangdong Province in southern China, there had encountered live bats, another Chinese delicacy sold in the markets. Farmed civets are believed to have been infected by the SARS virus from bats either because the civets were farmed in areas close to bat colonies or the virus jumped species when the two hosts came into contact at live animal markets.
Nevertheless, civet cat farming is again a thriving industry in southeast Asia, and live animal markets are the norm, not the exception.
Intensification of farming systems – of both traditional livestock and wildlife species – is on the increase and will continue to carry inherent risks to ecosystems, food security, animal health and human health, unless managed carefully through a One Health lens.