5 minute read
Pesticides kill bees in Ethiopia
Janet Lowore, Bees for Development,1 Agincourt Street, Monmouth, NP25 3DZ, UK
Keywords: Lathyrus sativa, Malathion, organophosphorus insecticide
Farmers Tewebe Nigru and Muluken Anteneh live on a smallholding in the hills overlooking the expanse of the Andassa plain in northern Ethiopia. In addition to crops and cattle, like many Ethiopian farmers they are also beekeepers. Tewebe learnt beekeeping from his father and has kept bees all his life and says: “In the past I had many more colonies but due to deforestation and lack of bee forage the number has reduced. These days bees are dying also from poisons”. When the main growing season ends, to shore up food supplies, many farmers plant grass pea Lathyrus sativa as it grows well in the dry season, benefiting from residual moisture in the soil. However, possibly because it is one of the few plants to flower at this time of year, it is attractive to both honey bees and insect pests. Farmers intentionally apply insecticides to tackle the pests, and unintentionally kill honey bees at the same time. The pest incidence associated with Lathyrus sativa used not to be so severe but - with intensification of planting – so has followed intensification of pest attack. Farmers habitually spray the flowering crop with Malathion. Tewebe explained that he understands that it is this pesticide that is affecting his bees because he detects that the colonies dwindle during this period and he observes dead bees in the fields.
Malathion
Malathion is an organophosphorus, synthetic insecticide used widely in agriculture and also to kill insects to protect public health. This pesticide is categorised as highly toxic to honey bees. The Pacific Northwest Extension Publication How to reduce bee poisoning from pesticides 1 states that it should never be applied to flowering crops and has a 2-5 day residual toxic effect. The Apiculture Programme of North Carolina State University states 2 Malathion to be “highly toxic” and that “severe bee losses may be expected” when used in the vicinity of honey bees.
1 www.cru.cahe.wsu.edu/cepublications/pnw0518/pnw0518.pdf
2 www.cals.ncsu.edu/entomology/apiculture/pdfs/2.12%20copy.pdf
GENERAL ADVICE TO AVOID PESTICIDE POISONING
• Choose pesticides which are not the most toxic
• Apply pesticides before the crop is in flower
• Apply pesticides at night, when honey bees are not foraging
• Beekeepers can temporarily confine their bees to the hives by closing the entrances – but this can only be done for a short time and where there is no risk of the colony overheating
20 YEARS OF BfD
In BfDJ 34 (March 1995) we published our first full colour centre fold Bees and Pesticides written by Ole Hertz*. The article offered suggestions for protecting bees against pesticides which are still pertinent today.
How to protect bees against pesticides
Beekeepers can help reduce bee poisoning in different ways:
• Bees can be kept at a distance safe from areas where pesticides are being applied. This must be at least 7 km, although the farmer will not get crops pollinated.
• The beekeeper and the farmer can co-operate. If beekeepers learn about different pesticides, they can discuss with farmers, warn them against the most dangerous pesticides and develop beneficial agreements concerning pollination services and the prudent use of pesticides.
• Bees can be moved away before the spraying and kept away as long as the poisons are still in the flowers.
• If pesticides are used on flowering plants near hives, and it is too difficult to move the hives away, the bees can be confined inside the hives. The hives can be covered by large burlap sacks. It is necessary to put water on the sacks to cool the bees. The bees should also be provided with water inside the hives, so that they are able to cool the brood. If the hives are placed in shade, and the sacking is kept wet, the bees can be covered for up to two days.
• It may be necessary to apply water to the sacking every 1-3 hours to keep the colony sufficiently cool - overheating of a colony can lead to rapid death. Larger colonies are more sensitive to overheating than small, and it is important that there is plenty of space and good ventilation in the hive.
• If the bees are near a water pipe it can be possible to keep them inside their hive by constantly sprinkling them, so that they believe it is a rainy day.
* available at www.beesfordevelopment.org/portal
EU RESCUE PLAN
The EU has launched a ban on three widely used neonicitinoid 1 pesticides that the European Food Safety Authority (EFSA) says pose “high acute risks” to pollinators. Member States are requested to suspend for two years the use of these pesticides on seeds, granular atom sprays and for crops that attract bees – cotton, maize rape and sunflower. After a vote on the two-year ban the Commission hopes to have a proposal ready by March and law by 1 July 2013.
Source: Arthur Neslen, www.Euractive.com
Neonicotinoids are insecticides that affect the central nervous system of insects, causing paralysis and death. A number of recent studies have suggested that exposure to neonicotinoids at sub-lethal doses can have significant negative effects on bee health and bee colonies.
EFSA MEETINGS
Scientific Colloquium to discuss holistic approaches to the risk assessment of multiple stressors in bees
EFSA will share and debate developments in bee health risk assessment with a range of stakeholders and scientific experts at national, European and international levels on 15-16 May 2013. Discussion will cover issues including: protection of pollination services; monitoring of bee colonies and testing stressors in bees; and assessment of multiple stressors to bees including chemicals and diseases. Stakeholders wishing to attend can register their interest online.
Workshop on the risk assessment of plant protection products on bees
A one-day workshop in September 2013 will present to Member States, applicants and all stakeholders the new EFSA guidance on the Risk Assessment of Plant Protection Products on Bees (Apis mellifera, Bombus spp and solitary bees), which is due to be published in May, following a second round of public consultation. How to register for the event will be published in May.
Source: www.efsa.europa.eu/en/events/event/130515.htm