Bambalutas

DEATH’S HEAD HAWK MOTH

by Ole Hertz, Denmark

Death’s head hawk moths present a seasonal problem for beekeeping in Cape Verde.

They are known in Cape Verde as Bambalutas: Latin name is Acherontia atropos. The moths are large (about 7cm long) grey/brown in colour, and with beautiful yellow hind wings. They are named after the pattern on their thorax, that resembles a ‘death’s head’ or skull pattern. Acherontia atropos occurs in a few areas of Europe and Africa: other species of Acherontia are found in Asia. The green larvae feed on the leaves of potatoes, tomatoes and other plants. The adults feed mainly on sap from tree wounds.

After the rainy season, which in Cape Verde means several days of showers in the autumn, bambalutas can be seen in great numbers. The bambalutas are attracted to the smell of honey and will wait around near the nests of bees and also try to enter hives.

If a large number of bambalutas get into a hive, the bees may be so disturbed that they will abscond. The bees will sting and kill some bambalutas, but their numbers can be so great that it is impossible for the bees to keep them out. The moths that are killed in the hive are embalmed in propolis by the bees and are found in large numbers inside the hive. Many moths get stuck in the hive entrance and sometimes it becomes completely blocked by the moths.

During an earlier beekeeping project in Cape Verde a special screen was invented to place in front of the hive entrance. This allows the bees to enter the hive and prevents the large bambalutas from doing so. Some moths still manage to get into the hive at the entrance and through any other cracks and gaps.

These screens are needed for the few months during which the bees are constantly under stress from the attempts by the moths to get into the hives. This problem is particularly bad at night when the moths are at their most active, and it is easy to hear that the bees are upset.

In the ‘bambaluta period’ a thick layer of dead, unpleasant smelling bambalutas are found in front of the hives with dust from their wings filling the air. The live bambalutas land in great numbers on beekeepers working with the bees. If you grab a bambaluta it produces a loud whistling sound. For bee and human health reasons the beekeepers should remove the dead bambalutas.

It is a mystery how the wild bee colonies avoid this bambaluta problem. Often the entrance to the nest is so small that the moths cannot enter or the colonies are so high in the mountains that the bambalutas cannot thrive.

This will be the objective of research during the Danida-funded project. We will experiment with new types of hives with ventilation in the top to attract the moths and to keep them away from the hive entrance.

Protect yours bees against pesticides

by Ole Hertz, Denmark

Increasing numbers of farmers in the tropics have access to pesticides. However, understandable informati on about the use and risks of using is not so easily available

Farmers want to protect their crops. When they are told that the answer lies with using one or other type of pesticide, they believe it and use it, not knowing that the producer wants to get rid of his stores: sometimes the pesticide is no longer allowed in other countries because it is dangerous.

If pesticides have to be used, they qust be applied in the right amount, at the right time, and with sufficient prote stive clothing for the user.

The misuse of pesticides creates a number of environmental problems such as water pollution, poisoning of the user, or the people eating the sprayed products. The wrong use of a pesticide can al 30 lead to the elimination of beneficial pollinating insects (wild bees and hive bees) and the natural enemies of the pests including predatory insects and birds.

Pesticides that are made for killing insects are called insecticides. Insecticides are especially dangerous for bees. If they are applied in the day, during the flowering period of the crops, they can kill so many bees that the crop fails due to lack of pollination.

How can bee poisoning be avoided?

First of all the beekeeper and the farmer must co-operate. Farmers must be made aware that the bees are of great benefit to them and beekeepers must be informed of what is going on at the farms near where their bees are foraging.

All beekeepers should be able to tell farmers about the pollination work of bees and advise them how to use pesticides in the least harmful way. There are some insecticides available with a repellent smell that means the bees abandon the sprayed flowers instantly: farmers need to know the importance of this. The most useful protection for bees is to avoid spraying flowering crops during the day. Unfortunately some pesticides are poisonous for several days. In this case, if spraying is necessary, the bees should be moved several! kilometres away. This is however difficult and disturbs the bees. If it is too difficult to move the bees, they can be confined inside their hives.

To do this it is necessary to prevent} the bees in the hives getting too hot. The hives must be covered with wet sacks and inside the hives the bees must be fed with water to help them keep t le brood cool. Water must be applied to the sacks on the hives every two hours during the day if the hives are not in the shade. Larger colonies are the most sensitive to the overheating that can lead to rapid death. It is also important to allow plenty of space and give good ventilation to the hive.

The Cape Verde example

Most farmers in Cape Verde are un aware of the benefits of pollination by bees. It is necessary to inform them of the importance and potential of beekeeping and pollination from the very beginning. This not only prevents the wrong use of pesticides, but also protects the be bees against direct destruction.

When the Ministry of Agriculture tried to transfer honeybees for pollination purposes to islands on Cape Verde other than Santiago the colonies were destroyed by the local people who believed that the bees were pests spoiling the flowers they visited. We hope to be able to provide the correct information by organising meetings and producing posters telling of the benefits of bees and pollination.

Pollination is essential for enhancing crop production without cross-pollination by bees many crops will not even produce seeds of fruit.

The author described in detail the symptoms of bee poisoning and alternatives to pesticides in B&D34 (1995).